diff --git a/lib/tsc.js b/lib/tsc.js
index 97db13aa62a50..ab79f9e91feec 100644
--- a/lib/tsc.js
+++ b/lib/tsc.js
@@ -69,7 +69,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
 var ts;
 (function (ts) {
     ts.versionMajorMinor = "4.8";
-    ts.version = "4.8.2";
+    ts.version = "4.8.3";
     var NativeCollections;
     (function (NativeCollections) {
         var globals = typeof globalThis !== "undefined" ? globalThis :
@@ -6031,7 +6031,7 @@ var ts;
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashnode_and_then_add_node_to_the_types_field_in_your_tsconfig: diag(2591, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashno_2591", "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i --save-dev @types/node` and then add 'node' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slashjquery_and_then_add_jquery_to_the_types_field_in_your_tsconfig: diag(2592, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slash_2592", "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i --save-dev @types/jquery` and then add 'jquery' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_types_Slashjest_or_npm_i_save_dev_types_Slashmocha_and_then_add_jest_or_mocha_to_the_types_field_in_your_tsconfig: diag(2593, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_type_2593", "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i --save-dev @types/jest` or `npm i --save-dev @types/mocha` and then add 'jest' or 'mocha' to the types field in your tsconfig."),
-        This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the__2594", "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag."),
+        This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag_2594", "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag."),
         _0_can_only_be_imported_by_using_a_default_import: diag(2595, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_default_import_2595", "'{0}' can only be imported by using a default import."),
         _0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import: diag(2596, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import_2596", "'{0}' can only be imported by turning on the 'esModuleInterop' flag and using a default import."),
         _0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import: diag(2597, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import_2597", "'{0}' can only be imported by using a 'require' call or by using a default import."),
@@ -36545,7 +36545,7 @@ var ts;
                 var _a, _b;
                 if (path === undefined)
                     return path;
-                return ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames })(ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a)));
+                return ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a));
             }
             function combineDirectoryPath(root, dir) {
                 return ts.ensureTrailingDirectorySeparator(ts.combinePaths(root, dir));
@@ -36560,7 +36560,7 @@ var ts;
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? ts.startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)) {
+                    && (state.compilerOptions.configFile ? ts.containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)) {
                     var getCanonicalFileName = ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames });
                     var commonSourceDirGuesses = [];
                     if (state.compilerOptions.rootDir || (state.compilerOptions.composite && state.compilerOptions.configFilePath)) {
@@ -36590,7 +36590,7 @@ var ts;
                         var candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (var _e = 0, candidateDirectories_1 = candidateDirectories; _e < candidateDirectories_1.length; _e++) {
                             var candidateDir = candidateDirectories_1[_e];
-                            if (ts.startsWith(finalPath, candidateDir)) {
+                            if (ts.containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 var pathFragment = finalPath.slice(candidateDir.length + 1);
                                 var possibleInputBase = ts.combinePaths(commonSourceDirGuess, pathFragment);
                                 var jsAndDtsExtensions = [".mjs", ".cjs", ".js", ".json", ".d.mts", ".d.cts", ".d.ts"];
@@ -41875,40 +41875,60 @@ var ts;
             return typeof file.externalModuleIndicator !== "object" && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), undefined, dontResolveAlias);
         }
         function getTargetOfImportClause(node, dontResolveAlias) {
-            var _a;
             var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                var exportDefaultSymbol = void 0;
-                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default", node, dontResolveAlias);
-                }
-                var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
-                var hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        var exportEqualsSymbol = moduleSymbol.exports.get("export=");
-                        var exportAssignment = exportEqualsSymbol.valueDeclaration;
-                        var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-                        if (exportAssignment) {
-                            ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+        function getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias) {
+            var _a;
+            var exportDefaultSymbol;
+            if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, "default", node, dontResolveAlias);
+            }
+            var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
+            var specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            var hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    var exportEqualsSymbol = moduleSymbol.exports.get("export=");
+                    var exportAssignment = exportEqualsSymbol.valueDeclaration;
+                    var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+                    if (exportAssignment) {
+                        ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, false);
-                    return resolved;
+                else if (ts.isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
+                }
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, ts.isImportOrExportSpecifier(node) && node.propertyName || node.name);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, undefined, false);
-                return exportDefaultSymbol;
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, undefined, false);
+            return exportDefaultSymbol;
+        }
+        function getModuleSpecifierForImportOrExport(node) {
+            switch (node.kind) {
+                case 267: return node.parent.moduleSpecifier;
+                case 265: return ts.isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case 268: return node.parent.parent.moduleSpecifier;
+                case 270: return node.parent.parent.parent.moduleSpecifier;
+                case 275: return node.parent.parent.moduleSpecifier;
+                default: return ts.Debug.assertNever(node);
             }
         }
         function reportNonDefaultExport(moduleSymbol, node) {
@@ -41980,7 +42000,7 @@ var ts;
             }
         }
         function getExternalModuleMember(node, specifier, dontResolveAlias) {
-            var _a, _b;
+            var _a;
             if (dontResolveAlias === void 0) { dontResolveAlias = false; }
             var moduleSpecifier = ts.getExternalModuleRequireArgument(node) || node.moduleSpecifier;
             var moduleSymbol = resolveExternalModuleName(node, moduleSpecifier);
@@ -42014,29 +42034,33 @@ var ts;
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        var moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        var declarationName = ts.declarationNameToString(name);
-                        var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            var suggestionName = symbolToString(suggestion);
-                            var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
-                            }
-                        }
-                        else {
-                            if ((_b = moduleSymbol.exports) === null || _b === void 0 ? void 0 : _b.has("default")) {
-                                error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
+        function errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name) {
+            var _a;
+            var moduleName = getFullyQualifiedName(moduleSymbol, node);
+            var declarationName = ts.declarationNameToString(name);
+            var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                var suggestionName = symbolToString(suggestion);
+                var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
+                }
+            }
+            else {
+                if ((_a = moduleSymbol.exports) === null || _a === void 0 ? void 0 : _a.has("default")) {
+                    error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
         function reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName) {
             var _a, _b;
             var localSymbol = (_b = (_a = moduleSymbol.valueDeclaration) === null || _a === void 0 ? void 0 : _a.locals) === null || _b === void 0 ? void 0 : _b.get(name.escapedText);
@@ -42082,6 +42106,13 @@ var ts;
             }
         }
         function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            if (ts.isImportSpecifier(node) && ts.idText(node.propertyName || node.name) === "default") {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             var root = ts.isBindingElement(node) ? ts.getRootDeclaration(node) : node.parent.parent.parent;
             var commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             var resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -42103,6 +42134,13 @@ var ts;
             return resolved;
         }
         function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            if (ts.idText(node.propertyName || node.name) === "default") {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             var resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, false, dontResolveAlias);
@@ -51674,7 +51712,7 @@ var ts;
                 return includes & 8388608 ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & 98304) {
-                return includes & 32768 ? undefinedType : nullType;
+                return includes & 16777216 ? neverType : includes & 32768 ? undefinedType : nullType;
             }
             if (includes & 4 && includes & (128 | 134217728 | 268435456) ||
                 includes & 8 && includes & 256 ||
@@ -52309,7 +52347,7 @@ var ts;
                     type;
         }
         function distributeIndexOverObjectType(objectType, indexType, writing) {
-            if (objectType.flags & 3145728) {
+            if (objectType.flags & 1048576 || objectType.flags & 2097152 && !shouldDeferIndexType(objectType)) {
                 var types = ts.map(objectType.types, function (t) { return getSimplifiedType(getIndexedAccessType(t, indexType), writing); });
                 return objectType.flags & 2097152 || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -54448,7 +54486,7 @@ var ts;
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & 2097152) {
+            if (type.flags & 2097152 && ts.some(type.types, isEmptyAnonymousObjectType)) {
                 var normalizedTypes = ts.sameMap(type.types, function (t) { return getNormalizedType(t, writing); });
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -55432,7 +55470,7 @@ var ts;
                                 if (reportErrors && originalErrorInfo) {
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, 2, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, 2, reportErrors, undefined, intersectionState)) {
                                     return result;
                                 }
                                 if (reportErrors && originalErrorInfo && errorInfo) {
@@ -55495,8 +55533,8 @@ var ts;
                     if (!c.root.inferTypeParameters && !isDistributionDependent(c.root)) {
                         var skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         var skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
-                        if (result = skipTrue ? -1 : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2, false)) {
-                            result &= skipFalse ? -1 : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2, false);
+                        if (result = skipTrue ? -1 : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2, false, undefined, intersectionState)) {
+                            result &= skipFalse ? -1 : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2, false, undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -59855,7 +59893,7 @@ var ts;
                 var narrowedPropType = narrowType(propType);
                 return filterType(type, function (t) {
                     var discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & 131072) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & 131072) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
             function narrowTypeByDiscriminantProperty(type, access, operator, value, assumeTrue) {
@@ -59904,7 +59942,7 @@ var ts;
             }
             function narrowByInKeyword(type, name, assumeTrue) {
                 if (type.flags & 1048576
-                    || type.flags & 524288 && declaredType !== type
+                    || type.flags & 524288 && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || ts.isThisTypeParameter(type)
                     || type.flags & 2097152 && ts.every(type.types, function (t) { return t.symbol !== globalThisSymbol; })) {
                     return filterType(type, function (t) { return isTypePresencePossible(t, name, assumeTrue); });
@@ -60024,14 +60062,18 @@ var ts;
                     assumeTrue = !assumeTrue;
                 }
                 var valueType = getTypeOfExpression(value);
-                if ((type.flags & 2) && assumeTrue && (operator === 36 || operator === 37)) {
+                if (((type.flags & 2) || isEmptyAnonymousObjectType(type) && !(valueType.flags & 98304)) &&
+                    assumeTrue &&
+                    (operator === 36 || operator === 37)) {
                     if (valueType.flags & (131068 | 67108864)) {
                         return valueType;
                     }
                     if (valueType.flags & 524288) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & 2) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & 98304) {
                     if (!strictNullChecks) {
@@ -60426,7 +60468,9 @@ var ts;
                 !!(type.flags & 465829888 && getBaseConstraintOrType(type).flags & (98304 | 1048576));
         }
         function isGenericTypeWithoutNullableConstraint(type) {
-            return !!(type.flags & 465829888 && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304));
+            return type.flags & 2097152 ?
+                ts.some(type.types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & 465829888 && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304));
         }
         function hasContextualTypeWithNoGenericTypes(node, checkMode) {
             var contextualType = (ts.isIdentifier(node) || ts.isPropertyAccessExpression(node) || ts.isElementAccessExpression(node)) &&
@@ -105437,9 +105481,7 @@ var ts;
                 }
             }
         }
-        var seenRefs = buildInfoPath ? new ts.Set() : undefined;
         var buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs === null || seenRefs === void 0 ? void 0 : seenRefs.add(resolvedPath);
         var pseudoUpToDate = false;
         var usesPrepend = false;
         var upstreamChangedProject;
@@ -105450,7 +105492,7 @@ var ts;
                 if (refStatus.newestInputFileTime && refStatus.newestInputFileTime <= oldestOutputFileTime) {
                     continue;
                 }
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: ts.UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath,
@@ -105501,24 +105543,9 @@ var ts;
             oldestOutputFileName: oldestOutputFileName
         };
     }
-    function hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath) {
-        if (seenRefs.has(resolvedRefPath))
-            return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath) {
         var refBuildInfo = state.buildInfoCache.get(resolvedRefPath);
-        if (refBuildInfo.path === buildInfoCacheEntry.path)
-            return true;
-        if (resolvedConfig.projectReferences) {
-            for (var _i = 0, _a = resolvedConfig.projectReferences; _i < _a.length; _i++) {
-                var ref = _a[_i];
-                var resolvedRef = ts.resolveProjectReferencePath(ref);
-                var resolvedRefPath_1 = toResolvedConfigFilePath(state, resolvedRef);
-                var resolvedConfig_1 = parseConfigFile(state, resolvedRef, resolvedRefPath_1);
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig_1, resolvedRefPath_1))
-                    return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
     function getUpToDateStatus(state, project, resolvedPath) {
         if (project === undefined) {
diff --git a/lib/tsserver.js b/lib/tsserver.js
index 481cb5866634e..b696263504d68 100644
--- a/lib/tsserver.js
+++ b/lib/tsserver.js
@@ -109,7 +109,7 @@ var ts;
     // The following is baselined as a literal template type without intervention
     /** The version of the TypeScript compiler release */
     // eslint-disable-next-line @typescript-eslint/no-inferrable-types
-    ts.version = "4.8.2";
+    ts.version = "4.8.3";
     /* @internal */
     var Comparison;
     (function (Comparison) {
@@ -8875,7 +8875,7 @@ var ts;
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashnode_and_then_add_node_to_the_types_field_in_your_tsconfig: diag(2591, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashno_2591", "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i --save-dev @types/node` and then add 'node' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slashjquery_and_then_add_jquery_to_the_types_field_in_your_tsconfig: diag(2592, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slash_2592", "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i --save-dev @types/jquery` and then add 'jquery' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_types_Slashjest_or_npm_i_save_dev_types_Slashmocha_and_then_add_jest_or_mocha_to_the_types_field_in_your_tsconfig: diag(2593, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_type_2593", "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i --save-dev @types/jest` or `npm i --save-dev @types/mocha` and then add 'jest' or 'mocha' to the types field in your tsconfig."),
-        This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the__2594", "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag."),
+        This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag_2594", "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag."),
         _0_can_only_be_imported_by_using_a_default_import: diag(2595, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_default_import_2595", "'{0}' can only be imported by using a default import."),
         _0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import: diag(2596, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import_2596", "'{0}' can only be imported by turning on the 'esModuleInterop' flag and using a default import."),
         _0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import: diag(2597, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import_2597", "'{0}' can only be imported by using a 'require' call or by using a default import."),
@@ -44636,7 +44636,7 @@ var ts;
                 var _a, _b;
                 if (path === undefined)
                     return path;
-                return ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames })(ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a)));
+                return ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a));
             }
             function combineDirectoryPath(root, dir) {
                 return ts.ensureTrailingDirectorySeparator(ts.combinePaths(root, dir));
@@ -44656,7 +44656,7 @@ var ts;
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? ts.startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)) {
+                    && (state.compilerOptions.configFile ? ts.containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)) {
                     // So that all means we'll only try these guesses for files outside `node_modules` in a directory where the `package.json` and `tsconfig.json` are siblings.
                     // Even with all that, we still don't know if the root of the output file structure will be (relative to the package file)
                     // `.`, `./src` or any other deeper directory structure. (If project references are used, it's definitely `.` by fiat, so that should be pretty common.)
@@ -44712,7 +44712,7 @@ var ts;
                         var candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (var _e = 0, candidateDirectories_1 = candidateDirectories; _e < candidateDirectories_1.length; _e++) {
                             var candidateDir = candidateDirectories_1[_e];
-                            if (ts.startsWith(finalPath, candidateDir)) {
+                            if (ts.containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 // The matched export is looking up something in either the out declaration or js dir, now map the written path back into the source dir and source extension
                                 var pathFragment = finalPath.slice(candidateDir.length + 1); // +1 to also remove directory seperator
                                 var possibleInputBase = ts.combinePaths(commonSourceDirGuess, pathFragment);
@@ -50994,41 +50994,61 @@ var ts;
             return typeof file.externalModuleIndicator !== "object" && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), /*sourceNode*/ undefined, dontResolveAlias);
         }
         function getTargetOfImportClause(node, dontResolveAlias) {
-            var _a;
             var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                var exportDefaultSymbol = void 0;
-                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
-                }
-                var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
-                var hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
-                        var exportAssignment = exportEqualsSymbol.valueDeclaration;
-                        var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-                        if (exportAssignment) {
-                            ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+        function getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias) {
+            var _a;
+            var exportDefaultSymbol;
+            if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
+            }
+            var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
+            var specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            var hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
+                    var exportAssignment = exportEqualsSymbol.valueDeclaration;
+                    var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+                    if (exportAssignment) {
+                        ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
-                    var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
-                    return resolved;
+                else if (ts.isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
-                return exportDefaultSymbol;
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, ts.isImportOrExportSpecifier(node) && node.propertyName || node.name);
+                }
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
+            return exportDefaultSymbol;
+        }
+        function getModuleSpecifierForImportOrExport(node) {
+            switch (node.kind) {
+                case 267 /* SyntaxKind.ImportClause */: return node.parent.moduleSpecifier;
+                case 265 /* SyntaxKind.ImportEqualsDeclaration */: return ts.isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case 268 /* SyntaxKind.NamespaceImport */: return node.parent.parent.moduleSpecifier;
+                case 270 /* SyntaxKind.ImportSpecifier */: return node.parent.parent.parent.moduleSpecifier;
+                case 275 /* SyntaxKind.ExportSpecifier */: return node.parent.parent.moduleSpecifier;
+                default: return ts.Debug.assertNever(node);
             }
         }
         function reportNonDefaultExport(moduleSymbol, node) {
@@ -51118,7 +51138,7 @@ var ts;
             }
         }
         function getExternalModuleMember(node, specifier, dontResolveAlias) {
-            var _a, _b;
+            var _a;
             if (dontResolveAlias === void 0) { dontResolveAlias = false; }
             var moduleSpecifier = ts.getExternalModuleRequireArgument(node) || node.moduleSpecifier;
             var moduleSymbol = resolveExternalModuleName(node, moduleSpecifier); // TODO: GH#18217
@@ -51154,29 +51174,33 @@ var ts;
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        var moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        var declarationName = ts.declarationNameToString(name);
-                        var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            var suggestionName = symbolToString(suggestion);
-                            var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
-                            }
-                        }
-                        else {
-                            if ((_b = moduleSymbol.exports) === null || _b === void 0 ? void 0 : _b.has("default" /* InternalSymbolName.Default */)) {
-                                error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
+        function errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name) {
+            var _a;
+            var moduleName = getFullyQualifiedName(moduleSymbol, node);
+            var declarationName = ts.declarationNameToString(name);
+            var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                var suggestionName = symbolToString(suggestion);
+                var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
+                }
+            }
+            else {
+                if ((_a = moduleSymbol.exports) === null || _a === void 0 ? void 0 : _a.has("default" /* InternalSymbolName.Default */)) {
+                    error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
         function reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName) {
             var _a, _b;
             var localSymbol = (_b = (_a = moduleSymbol.valueDeclaration) === null || _a === void 0 ? void 0 : _a.locals) === null || _b === void 0 ? void 0 : _b.get(name.escapedText);
@@ -51222,6 +51246,13 @@ var ts;
             }
         }
         function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            if (ts.isImportSpecifier(node) && ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             var root = ts.isBindingElement(node) ? ts.getRootDeclaration(node) : node.parent.parent.parent;
             var commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             var resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -51243,6 +51274,13 @@ var ts;
             return resolved;
         }
         function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            if (ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             var resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
@@ -62193,7 +62231,7 @@ var ts;
                 return includes & 8388608 /* TypeFlags.IncludesWildcard */ ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & 98304 /* TypeFlags.Nullable */) {
-                return includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
+                return includes & 16777216 /* TypeFlags.IncludesEmptyObject */ ? neverType : includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
             }
             if (includes & 4 /* TypeFlags.String */ && includes & (128 /* TypeFlags.StringLiteral */ | 134217728 /* TypeFlags.TemplateLiteral */ | 268435456 /* TypeFlags.StringMapping */) ||
                 includes & 8 /* TypeFlags.Number */ && includes & 256 /* TypeFlags.NumberLiteral */ ||
@@ -62883,7 +62921,7 @@ var ts;
             // (T | U)[K] -> T[K] | U[K] (reading)
             // (T | U)[K] -> T[K] & U[K] (writing)
             // (T & U)[K] -> T[K] & U[K]
-            if (objectType.flags & 3145728 /* TypeFlags.UnionOrIntersection */) {
+            if (objectType.flags & 1048576 /* TypeFlags.Union */ || objectType.flags & 2097152 /* TypeFlags.Intersection */ && !shouldDeferIndexType(objectType)) {
                 var types = ts.map(objectType.types, function (t) { return getSimplifiedType(getIndexedAccessType(t, indexType), writing); });
                 return objectType.flags & 2097152 /* TypeFlags.Intersection */ || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -65291,7 +65329,7 @@ var ts;
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & 2097152 /* TypeFlags.Intersection */) {
+            if (type.flags & 2097152 /* TypeFlags.Intersection */ && ts.some(type.types, isEmptyAnonymousObjectType)) {
                 var normalizedTypes = ts.sameMap(type.types, function (t) { return getNormalizedType(t, writing); });
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -66462,7 +66500,7 @@ var ts;
                                     // create a new chain for the constraint error
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors, /* headMessage */ undefined, intersectionState)) {
                                     return result;
                                 }
                                 // prefer the shorter chain of the constraint comparison chain, and the direct comparison chain
@@ -66554,8 +66592,8 @@ var ts;
                         var skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         var skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
                         // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false)) {
-                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false);
+                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState)) {
+                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -71584,7 +71622,7 @@ var ts;
                 var narrowedPropType = narrowType(propType);
                 return filterType(type, function (t) {
                     var discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
             function narrowTypeByDiscriminantProperty(type, access, operator, value, assumeTrue) {
@@ -71633,7 +71671,7 @@ var ts;
             }
             function narrowByInKeyword(type, name, assumeTrue) {
                 if (type.flags & 1048576 /* TypeFlags.Union */
-                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type
+                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || ts.isThisTypeParameter(type)
                     || type.flags & 2097152 /* TypeFlags.Intersection */ && ts.every(type.types, function (t) { return t.symbol !== globalThisSymbol; })) {
                     return filterType(type, function (t) { return isTypePresencePossible(t, name, assumeTrue); });
@@ -71766,14 +71804,18 @@ var ts;
                     assumeTrue = !assumeTrue;
                 }
                 var valueType = getTypeOfExpression(value);
-                if ((type.flags & 2 /* TypeFlags.Unknown */) && assumeTrue && (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
+                if (((type.flags & 2 /* TypeFlags.Unknown */) || isEmptyAnonymousObjectType(type) && !(valueType.flags & 98304 /* TypeFlags.Nullable */)) &&
+                    assumeTrue &&
+                    (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
                     if (valueType.flags & (131068 /* TypeFlags.Primitive */ | 67108864 /* TypeFlags.NonPrimitive */)) {
                         return valueType;
                     }
                     if (valueType.flags & 524288 /* TypeFlags.Object */) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & 2 /* TypeFlags.Unknown */) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & 98304 /* TypeFlags.Nullable */) {
                     if (!strictNullChecks) {
@@ -72232,7 +72274,9 @@ var ts;
                 !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && getBaseConstraintOrType(type).flags & (98304 /* TypeFlags.Nullable */ | 1048576 /* TypeFlags.Union */));
         }
         function isGenericTypeWithoutNullableConstraint(type) {
-            return !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
+            return type.flags & 2097152 /* TypeFlags.Intersection */ ?
+                ts.some(type.types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
         }
         function hasContextualTypeWithNoGenericTypes(node, checkMode) {
             // Computing the contextual type for a child of a JSX element involves resolving the type of the
@@ -126929,9 +126973,7 @@ var ts;
                 }
             }
         }
-        var seenRefs = buildInfoPath ? new ts.Set() : undefined;
         var buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs === null || seenRefs === void 0 ? void 0 : seenRefs.add(resolvedPath);
         /** Inputs are up-to-date, just need either timestamp update or bundle prepend manipulation to make it look up-to-date */
         var pseudoUpToDate = false;
         var usesPrepend = false;
@@ -126946,7 +126988,7 @@ var ts;
                     continue;
                 }
                 // Check if tsbuildinfo path is shared, then we need to rebuild
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: ts.UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath,
@@ -127004,25 +127046,9 @@ var ts;
             oldestOutputFileName: oldestOutputFileName
         };
     }
-    function hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath) {
-        if (seenRefs.has(resolvedRefPath))
-            return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath) {
         var refBuildInfo = state.buildInfoCache.get(resolvedRefPath);
-        if (refBuildInfo.path === buildInfoCacheEntry.path)
-            return true;
-        if (resolvedConfig.projectReferences) {
-            // Check references
-            for (var _i = 0, _a = resolvedConfig.projectReferences; _i < _a.length; _i++) {
-                var ref = _a[_i];
-                var resolvedRef = ts.resolveProjectReferencePath(ref);
-                var resolvedRefPath_1 = toResolvedConfigFilePath(state, resolvedRef);
-                var resolvedConfig_1 = parseConfigFile(state, resolvedRef, resolvedRefPath_1);
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig_1, resolvedRefPath_1))
-                    return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
     function getUpToDateStatus(state, project, resolvedPath) {
         if (project === undefined) {
@@ -171614,13 +171640,13 @@ var ts;
                     return __generator(this, function (_a) {
                         switch (_a.label) {
                             case 0:
-                                ts.Debug.assertIsDefined(host.importServicePlugin);
+                                ts.Debug.assertIsDefined(host.importPlugin);
                                 resolvedPath = ts.combinePaths(initialDir, "node_modules");
                                 log("Dynamically importing ".concat(moduleName, " from ").concat(initialDir, " (resolved to ").concat(resolvedPath, ")"));
                                 _a.label = 1;
                             case 1:
                                 _a.trys.push([1, 3, , 4]);
-                                return [4 /*yield*/, host.importServicePlugin(resolvedPath, moduleName)];
+                                return [4 /*yield*/, host.importPlugin(resolvedPath, moduleName)];
                             case 2:
                                 result = _a.sent();
                                 return [3 /*break*/, 4];
@@ -172699,7 +172725,7 @@ var ts;
             };
             Project.prototype.enableGlobalPlugins = function (options, pluginConfigOverrides) {
                 var host = this.projectService.host;
-                if (!host.require && !host.importServicePlugin) {
+                if (!host.require && !host.importPlugin) {
                     this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                     return;
                 }
@@ -172756,7 +172782,7 @@ var ts;
                     return __generator(this, function (_a) {
                         switch (_a.label) {
                             case 0:
-                                ts.Debug.assertIsDefined(this.projectService.host.importServicePlugin);
+                                ts.Debug.assertIsDefined(this.projectService.host.importPlugin);
                                 log = function (message) { return _this.projectService.logger.info(message); };
                                 logError = function (message) {
                                     (errorLogs !== null && errorLogs !== void 0 ? errorLogs : (errorLogs = [])).push(message);
@@ -173457,7 +173483,7 @@ var ts;
             /*@internal*/
             ConfiguredProject.prototype.enablePluginsWithOptions = function (options, pluginConfigOverrides) {
                 var host = this.projectService.host;
-                if (!host.require && !host.importServicePlugin) {
+                if (!host.require && !host.importPlugin) {
                     this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                     return;
                 }
@@ -176901,7 +176927,7 @@ var ts;
             /*@internal*/
             ProjectService.prototype.requestEnablePlugin = function (project, pluginConfigEntry, searchPaths, pluginConfigOverrides) {
                 var _a;
-                if (!this.host.importServicePlugin && !this.host.require) {
+                if (!this.host.importPlugin && !this.host.require) {
                     this.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                     return;
                 }
@@ -176911,7 +176937,7 @@ var ts;
                     return;
                 }
                 // If the host supports dynamic import, begin enabling the plugin asynchronously.
-                if (this.host.importServicePlugin) {
+                if (this.host.importPlugin) {
                     var importPromise = project.beginEnablePluginAsync(pluginConfigEntry, searchPaths, pluginConfigOverrides);
                     (_a = this.pendingPluginEnablements) !== null && _a !== void 0 ? _a : (this.pendingPluginEnablements = new ts.Map());
                     var promises = this.pendingPluginEnablements.get(project);
@@ -181210,7 +181236,7 @@ var ts;
                 setImmediate: function (x) { return setTimeout(x, 0); },
                 clearImmediate: function (handle) { return clearTimeout(handle); },
                 /* eslint-enable no-restricted-globals */
-                importServicePlugin: function (initialDir, moduleName) { return __awaiter(_this, void 0, void 0, function () {
+                importPlugin: function (initialDir, moduleName) { return __awaiter(_this, void 0, void 0, function () {
                     var packageRoot, packageJson, packageJsonResponse, e_1, browser, scriptPath, module_1, e_2;
                     return __generator(this, function (_a) {
                         switch (_a.label) {
diff --git a/lib/tsserverlibrary.d.ts b/lib/tsserverlibrary.d.ts
index 4744d065a38ac..8003ac00a3c64 100644
--- a/lib/tsserverlibrary.d.ts
+++ b/lib/tsserverlibrary.d.ts
@@ -7033,7 +7033,6 @@ declare namespace ts.server {
         gc?(): void;
         trace?(s: string): void;
         require?(initialPath: string, moduleName: string): ModuleImportResult;
-        importServicePlugin?(root: string, moduleName: string): Promise<ModuleImportResult>;
     }
 }
 declare namespace ts.server {
diff --git a/lib/tsserverlibrary.js b/lib/tsserverlibrary.js
index 57276bce88f5a..53b8c929ba8f1 100644
--- a/lib/tsserverlibrary.js
+++ b/lib/tsserverlibrary.js
@@ -303,7 +303,7 @@ var ts;
     // The following is baselined as a literal template type without intervention
     /** The version of the TypeScript compiler release */
     // eslint-disable-next-line @typescript-eslint/no-inferrable-types
-    ts.version = "4.8.2";
+    ts.version = "4.8.3";
     /* @internal */
     var Comparison;
     (function (Comparison) {
@@ -9069,7 +9069,7 @@ var ts;
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashnode_and_then_add_node_to_the_types_field_in_your_tsconfig: diag(2591, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashno_2591", "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i --save-dev @types/node` and then add 'node' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slashjquery_and_then_add_jquery_to_the_types_field_in_your_tsconfig: diag(2592, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slash_2592", "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i --save-dev @types/jquery` and then add 'jquery' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_types_Slashjest_or_npm_i_save_dev_types_Slashmocha_and_then_add_jest_or_mocha_to_the_types_field_in_your_tsconfig: diag(2593, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_type_2593", "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i --save-dev @types/jest` or `npm i --save-dev @types/mocha` and then add 'jest' or 'mocha' to the types field in your tsconfig."),
-        This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the__2594", "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag."),
+        This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag_2594", "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag."),
         _0_can_only_be_imported_by_using_a_default_import: diag(2595, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_default_import_2595", "'{0}' can only be imported by using a default import."),
         _0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import: diag(2596, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import_2596", "'{0}' can only be imported by turning on the 'esModuleInterop' flag and using a default import."),
         _0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import: diag(2597, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import_2597", "'{0}' can only be imported by using a 'require' call or by using a default import."),
@@ -44830,7 +44830,7 @@ var ts;
                 var _a, _b;
                 if (path === undefined)
                     return path;
-                return ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames })(ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a)));
+                return ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a));
             }
             function combineDirectoryPath(root, dir) {
                 return ts.ensureTrailingDirectorySeparator(ts.combinePaths(root, dir));
@@ -44850,7 +44850,7 @@ var ts;
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? ts.startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)) {
+                    && (state.compilerOptions.configFile ? ts.containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)) {
                     // So that all means we'll only try these guesses for files outside `node_modules` in a directory where the `package.json` and `tsconfig.json` are siblings.
                     // Even with all that, we still don't know if the root of the output file structure will be (relative to the package file)
                     // `.`, `./src` or any other deeper directory structure. (If project references are used, it's definitely `.` by fiat, so that should be pretty common.)
@@ -44906,7 +44906,7 @@ var ts;
                         var candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (var _e = 0, candidateDirectories_1 = candidateDirectories; _e < candidateDirectories_1.length; _e++) {
                             var candidateDir = candidateDirectories_1[_e];
-                            if (ts.startsWith(finalPath, candidateDir)) {
+                            if (ts.containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 // The matched export is looking up something in either the out declaration or js dir, now map the written path back into the source dir and source extension
                                 var pathFragment = finalPath.slice(candidateDir.length + 1); // +1 to also remove directory seperator
                                 var possibleInputBase = ts.combinePaths(commonSourceDirGuess, pathFragment);
@@ -51188,41 +51188,61 @@ var ts;
             return typeof file.externalModuleIndicator !== "object" && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), /*sourceNode*/ undefined, dontResolveAlias);
         }
         function getTargetOfImportClause(node, dontResolveAlias) {
-            var _a;
             var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                var exportDefaultSymbol = void 0;
-                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
-                }
-                var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
-                var hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
-                        var exportAssignment = exportEqualsSymbol.valueDeclaration;
-                        var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-                        if (exportAssignment) {
-                            ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+        function getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias) {
+            var _a;
+            var exportDefaultSymbol;
+            if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
+            }
+            var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
+            var specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            var hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
+                    var exportAssignment = exportEqualsSymbol.valueDeclaration;
+                    var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+                    if (exportAssignment) {
+                        ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
-                    var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
-                    return resolved;
+                else if (ts.isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
-                return exportDefaultSymbol;
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, ts.isImportOrExportSpecifier(node) && node.propertyName || node.name);
+                }
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
+            return exportDefaultSymbol;
+        }
+        function getModuleSpecifierForImportOrExport(node) {
+            switch (node.kind) {
+                case 267 /* SyntaxKind.ImportClause */: return node.parent.moduleSpecifier;
+                case 265 /* SyntaxKind.ImportEqualsDeclaration */: return ts.isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case 268 /* SyntaxKind.NamespaceImport */: return node.parent.parent.moduleSpecifier;
+                case 270 /* SyntaxKind.ImportSpecifier */: return node.parent.parent.parent.moduleSpecifier;
+                case 275 /* SyntaxKind.ExportSpecifier */: return node.parent.parent.moduleSpecifier;
+                default: return ts.Debug.assertNever(node);
             }
         }
         function reportNonDefaultExport(moduleSymbol, node) {
@@ -51312,7 +51332,7 @@ var ts;
             }
         }
         function getExternalModuleMember(node, specifier, dontResolveAlias) {
-            var _a, _b;
+            var _a;
             if (dontResolveAlias === void 0) { dontResolveAlias = false; }
             var moduleSpecifier = ts.getExternalModuleRequireArgument(node) || node.moduleSpecifier;
             var moduleSymbol = resolveExternalModuleName(node, moduleSpecifier); // TODO: GH#18217
@@ -51348,29 +51368,33 @@ var ts;
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        var moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        var declarationName = ts.declarationNameToString(name);
-                        var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            var suggestionName = symbolToString(suggestion);
-                            var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
-                            }
-                        }
-                        else {
-                            if ((_b = moduleSymbol.exports) === null || _b === void 0 ? void 0 : _b.has("default" /* InternalSymbolName.Default */)) {
-                                error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
+        function errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name) {
+            var _a;
+            var moduleName = getFullyQualifiedName(moduleSymbol, node);
+            var declarationName = ts.declarationNameToString(name);
+            var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                var suggestionName = symbolToString(suggestion);
+                var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
+                }
+            }
+            else {
+                if ((_a = moduleSymbol.exports) === null || _a === void 0 ? void 0 : _a.has("default" /* InternalSymbolName.Default */)) {
+                    error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
         function reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName) {
             var _a, _b;
             var localSymbol = (_b = (_a = moduleSymbol.valueDeclaration) === null || _a === void 0 ? void 0 : _a.locals) === null || _b === void 0 ? void 0 : _b.get(name.escapedText);
@@ -51416,6 +51440,13 @@ var ts;
             }
         }
         function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            if (ts.isImportSpecifier(node) && ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             var root = ts.isBindingElement(node) ? ts.getRootDeclaration(node) : node.parent.parent.parent;
             var commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             var resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -51437,6 +51468,13 @@ var ts;
             return resolved;
         }
         function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            if (ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             var resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
@@ -62387,7 +62425,7 @@ var ts;
                 return includes & 8388608 /* TypeFlags.IncludesWildcard */ ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & 98304 /* TypeFlags.Nullable */) {
-                return includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
+                return includes & 16777216 /* TypeFlags.IncludesEmptyObject */ ? neverType : includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
             }
             if (includes & 4 /* TypeFlags.String */ && includes & (128 /* TypeFlags.StringLiteral */ | 134217728 /* TypeFlags.TemplateLiteral */ | 268435456 /* TypeFlags.StringMapping */) ||
                 includes & 8 /* TypeFlags.Number */ && includes & 256 /* TypeFlags.NumberLiteral */ ||
@@ -63077,7 +63115,7 @@ var ts;
             // (T | U)[K] -> T[K] | U[K] (reading)
             // (T | U)[K] -> T[K] & U[K] (writing)
             // (T & U)[K] -> T[K] & U[K]
-            if (objectType.flags & 3145728 /* TypeFlags.UnionOrIntersection */) {
+            if (objectType.flags & 1048576 /* TypeFlags.Union */ || objectType.flags & 2097152 /* TypeFlags.Intersection */ && !shouldDeferIndexType(objectType)) {
                 var types = ts.map(objectType.types, function (t) { return getSimplifiedType(getIndexedAccessType(t, indexType), writing); });
                 return objectType.flags & 2097152 /* TypeFlags.Intersection */ || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -65485,7 +65523,7 @@ var ts;
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & 2097152 /* TypeFlags.Intersection */) {
+            if (type.flags & 2097152 /* TypeFlags.Intersection */ && ts.some(type.types, isEmptyAnonymousObjectType)) {
                 var normalizedTypes = ts.sameMap(type.types, function (t) { return getNormalizedType(t, writing); });
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -66656,7 +66694,7 @@ var ts;
                                     // create a new chain for the constraint error
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors, /* headMessage */ undefined, intersectionState)) {
                                     return result;
                                 }
                                 // prefer the shorter chain of the constraint comparison chain, and the direct comparison chain
@@ -66748,8 +66786,8 @@ var ts;
                         var skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         var skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
                         // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false)) {
-                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false);
+                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState)) {
+                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -71778,7 +71816,7 @@ var ts;
                 var narrowedPropType = narrowType(propType);
                 return filterType(type, function (t) {
                     var discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
             function narrowTypeByDiscriminantProperty(type, access, operator, value, assumeTrue) {
@@ -71827,7 +71865,7 @@ var ts;
             }
             function narrowByInKeyword(type, name, assumeTrue) {
                 if (type.flags & 1048576 /* TypeFlags.Union */
-                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type
+                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || ts.isThisTypeParameter(type)
                     || type.flags & 2097152 /* TypeFlags.Intersection */ && ts.every(type.types, function (t) { return t.symbol !== globalThisSymbol; })) {
                     return filterType(type, function (t) { return isTypePresencePossible(t, name, assumeTrue); });
@@ -71960,14 +71998,18 @@ var ts;
                     assumeTrue = !assumeTrue;
                 }
                 var valueType = getTypeOfExpression(value);
-                if ((type.flags & 2 /* TypeFlags.Unknown */) && assumeTrue && (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
+                if (((type.flags & 2 /* TypeFlags.Unknown */) || isEmptyAnonymousObjectType(type) && !(valueType.flags & 98304 /* TypeFlags.Nullable */)) &&
+                    assumeTrue &&
+                    (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
                     if (valueType.flags & (131068 /* TypeFlags.Primitive */ | 67108864 /* TypeFlags.NonPrimitive */)) {
                         return valueType;
                     }
                     if (valueType.flags & 524288 /* TypeFlags.Object */) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & 2 /* TypeFlags.Unknown */) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & 98304 /* TypeFlags.Nullable */) {
                     if (!strictNullChecks) {
@@ -72426,7 +72468,9 @@ var ts;
                 !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && getBaseConstraintOrType(type).flags & (98304 /* TypeFlags.Nullable */ | 1048576 /* TypeFlags.Union */));
         }
         function isGenericTypeWithoutNullableConstraint(type) {
-            return !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
+            return type.flags & 2097152 /* TypeFlags.Intersection */ ?
+                ts.some(type.types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
         }
         function hasContextualTypeWithNoGenericTypes(node, checkMode) {
             // Computing the contextual type for a child of a JSX element involves resolving the type of the
@@ -127123,9 +127167,7 @@ var ts;
                 }
             }
         }
-        var seenRefs = buildInfoPath ? new ts.Set() : undefined;
         var buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs === null || seenRefs === void 0 ? void 0 : seenRefs.add(resolvedPath);
         /** Inputs are up-to-date, just need either timestamp update or bundle prepend manipulation to make it look up-to-date */
         var pseudoUpToDate = false;
         var usesPrepend = false;
@@ -127140,7 +127182,7 @@ var ts;
                     continue;
                 }
                 // Check if tsbuildinfo path is shared, then we need to rebuild
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: ts.UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath,
@@ -127198,25 +127240,9 @@ var ts;
             oldestOutputFileName: oldestOutputFileName
         };
     }
-    function hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath) {
-        if (seenRefs.has(resolvedRefPath))
-            return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath) {
         var refBuildInfo = state.buildInfoCache.get(resolvedRefPath);
-        if (refBuildInfo.path === buildInfoCacheEntry.path)
-            return true;
-        if (resolvedConfig.projectReferences) {
-            // Check references
-            for (var _i = 0, _a = resolvedConfig.projectReferences; _i < _a.length; _i++) {
-                var ref = _a[_i];
-                var resolvedRef = ts.resolveProjectReferencePath(ref);
-                var resolvedRefPath_1 = toResolvedConfigFilePath(state, resolvedRef);
-                var resolvedConfig_1 = parseConfigFile(state, resolvedRef, resolvedRefPath_1);
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig_1, resolvedRefPath_1))
-                    return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
     function getUpToDateStatus(state, project, resolvedPath) {
         if (project === undefined) {
@@ -171808,13 +171834,13 @@ var ts;
                     return __generator(this, function (_a) {
                         switch (_a.label) {
                             case 0:
-                                ts.Debug.assertIsDefined(host.importServicePlugin);
+                                ts.Debug.assertIsDefined(host.importPlugin);
                                 resolvedPath = ts.combinePaths(initialDir, "node_modules");
                                 log("Dynamically importing ".concat(moduleName, " from ").concat(initialDir, " (resolved to ").concat(resolvedPath, ")"));
                                 _a.label = 1;
                             case 1:
                                 _a.trys.push([1, 3, , 4]);
-                                return [4 /*yield*/, host.importServicePlugin(resolvedPath, moduleName)];
+                                return [4 /*yield*/, host.importPlugin(resolvedPath, moduleName)];
                             case 2:
                                 result = _a.sent();
                                 return [3 /*break*/, 4];
@@ -172893,7 +172919,7 @@ var ts;
             };
             Project.prototype.enableGlobalPlugins = function (options, pluginConfigOverrides) {
                 var host = this.projectService.host;
-                if (!host.require && !host.importServicePlugin) {
+                if (!host.require && !host.importPlugin) {
                     this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                     return;
                 }
@@ -172950,7 +172976,7 @@ var ts;
                     return __generator(this, function (_a) {
                         switch (_a.label) {
                             case 0:
-                                ts.Debug.assertIsDefined(this.projectService.host.importServicePlugin);
+                                ts.Debug.assertIsDefined(this.projectService.host.importPlugin);
                                 log = function (message) { return _this.projectService.logger.info(message); };
                                 logError = function (message) {
                                     (errorLogs !== null && errorLogs !== void 0 ? errorLogs : (errorLogs = [])).push(message);
@@ -173651,7 +173677,7 @@ var ts;
             /*@internal*/
             ConfiguredProject.prototype.enablePluginsWithOptions = function (options, pluginConfigOverrides) {
                 var host = this.projectService.host;
-                if (!host.require && !host.importServicePlugin) {
+                if (!host.require && !host.importPlugin) {
                     this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                     return;
                 }
@@ -177095,7 +177121,7 @@ var ts;
             /*@internal*/
             ProjectService.prototype.requestEnablePlugin = function (project, pluginConfigEntry, searchPaths, pluginConfigOverrides) {
                 var _a;
-                if (!this.host.importServicePlugin && !this.host.require) {
+                if (!this.host.importPlugin && !this.host.require) {
                     this.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                     return;
                 }
@@ -177105,7 +177131,7 @@ var ts;
                     return;
                 }
                 // If the host supports dynamic import, begin enabling the plugin asynchronously.
-                if (this.host.importServicePlugin) {
+                if (this.host.importPlugin) {
                     var importPromise = project.beginEnablePluginAsync(pluginConfigEntry, searchPaths, pluginConfigOverrides);
                     (_a = this.pendingPluginEnablements) !== null && _a !== void 0 ? _a : (this.pendingPluginEnablements = new ts.Map());
                     var promises = this.pendingPluginEnablements.get(project);
diff --git a/lib/typescript.js b/lib/typescript.js
index 49899ec44b380..3c93c04e0e47a 100644
--- a/lib/typescript.js
+++ b/lib/typescript.js
@@ -294,7 +294,7 @@ var ts;
     // The following is baselined as a literal template type without intervention
     /** The version of the TypeScript compiler release */
     // eslint-disable-next-line @typescript-eslint/no-inferrable-types
-    ts.version = "4.8.2";
+    ts.version = "4.8.3";
     /* @internal */
     var Comparison;
     (function (Comparison) {
@@ -9060,7 +9060,7 @@ var ts;
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashnode_and_then_add_node_to_the_types_field_in_your_tsconfig: diag(2591, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashno_2591", "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i --save-dev @types/node` and then add 'node' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slashjquery_and_then_add_jquery_to_the_types_field_in_your_tsconfig: diag(2592, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slash_2592", "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i --save-dev @types/jquery` and then add 'jquery' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_types_Slashjest_or_npm_i_save_dev_types_Slashmocha_and_then_add_jest_or_mocha_to_the_types_field_in_your_tsconfig: diag(2593, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_type_2593", "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i --save-dev @types/jest` or `npm i --save-dev @types/mocha` and then add 'jest' or 'mocha' to the types field in your tsconfig."),
-        This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the__2594", "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag."),
+        This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag_2594", "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag."),
         _0_can_only_be_imported_by_using_a_default_import: diag(2595, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_default_import_2595", "'{0}' can only be imported by using a default import."),
         _0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import: diag(2596, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import_2596", "'{0}' can only be imported by turning on the 'esModuleInterop' flag and using a default import."),
         _0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import: diag(2597, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import_2597", "'{0}' can only be imported by using a 'require' call or by using a default import."),
@@ -44821,7 +44821,7 @@ var ts;
                 var _a, _b;
                 if (path === undefined)
                     return path;
-                return ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames })(ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a)));
+                return ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a));
             }
             function combineDirectoryPath(root, dir) {
                 return ts.ensureTrailingDirectorySeparator(ts.combinePaths(root, dir));
@@ -44841,7 +44841,7 @@ var ts;
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? ts.startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)) {
+                    && (state.compilerOptions.configFile ? ts.containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)) {
                     // So that all means we'll only try these guesses for files outside `node_modules` in a directory where the `package.json` and `tsconfig.json` are siblings.
                     // Even with all that, we still don't know if the root of the output file structure will be (relative to the package file)
                     // `.`, `./src` or any other deeper directory structure. (If project references are used, it's definitely `.` by fiat, so that should be pretty common.)
@@ -44897,7 +44897,7 @@ var ts;
                         var candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (var _e = 0, candidateDirectories_1 = candidateDirectories; _e < candidateDirectories_1.length; _e++) {
                             var candidateDir = candidateDirectories_1[_e];
-                            if (ts.startsWith(finalPath, candidateDir)) {
+                            if (ts.containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 // The matched export is looking up something in either the out declaration or js dir, now map the written path back into the source dir and source extension
                                 var pathFragment = finalPath.slice(candidateDir.length + 1); // +1 to also remove directory seperator
                                 var possibleInputBase = ts.combinePaths(commonSourceDirGuess, pathFragment);
@@ -51179,41 +51179,61 @@ var ts;
             return typeof file.externalModuleIndicator !== "object" && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), /*sourceNode*/ undefined, dontResolveAlias);
         }
         function getTargetOfImportClause(node, dontResolveAlias) {
-            var _a;
             var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                var exportDefaultSymbol = void 0;
-                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
-                }
-                var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
-                var hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
-                        var exportAssignment = exportEqualsSymbol.valueDeclaration;
-                        var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-                        if (exportAssignment) {
-                            ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+        function getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias) {
+            var _a;
+            var exportDefaultSymbol;
+            if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
+            }
+            var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
+            var specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            var hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
+                    var exportAssignment = exportEqualsSymbol.valueDeclaration;
+                    var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+                    if (exportAssignment) {
+                        ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
-                    var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
-                    return resolved;
+                else if (ts.isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
-                return exportDefaultSymbol;
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, ts.isImportOrExportSpecifier(node) && node.propertyName || node.name);
+                }
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
+            return exportDefaultSymbol;
+        }
+        function getModuleSpecifierForImportOrExport(node) {
+            switch (node.kind) {
+                case 267 /* SyntaxKind.ImportClause */: return node.parent.moduleSpecifier;
+                case 265 /* SyntaxKind.ImportEqualsDeclaration */: return ts.isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case 268 /* SyntaxKind.NamespaceImport */: return node.parent.parent.moduleSpecifier;
+                case 270 /* SyntaxKind.ImportSpecifier */: return node.parent.parent.parent.moduleSpecifier;
+                case 275 /* SyntaxKind.ExportSpecifier */: return node.parent.parent.moduleSpecifier;
+                default: return ts.Debug.assertNever(node);
             }
         }
         function reportNonDefaultExport(moduleSymbol, node) {
@@ -51303,7 +51323,7 @@ var ts;
             }
         }
         function getExternalModuleMember(node, specifier, dontResolveAlias) {
-            var _a, _b;
+            var _a;
             if (dontResolveAlias === void 0) { dontResolveAlias = false; }
             var moduleSpecifier = ts.getExternalModuleRequireArgument(node) || node.moduleSpecifier;
             var moduleSymbol = resolveExternalModuleName(node, moduleSpecifier); // TODO: GH#18217
@@ -51339,29 +51359,33 @@ var ts;
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        var moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        var declarationName = ts.declarationNameToString(name);
-                        var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            var suggestionName = symbolToString(suggestion);
-                            var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
-                            }
-                        }
-                        else {
-                            if ((_b = moduleSymbol.exports) === null || _b === void 0 ? void 0 : _b.has("default" /* InternalSymbolName.Default */)) {
-                                error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
+        function errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name) {
+            var _a;
+            var moduleName = getFullyQualifiedName(moduleSymbol, node);
+            var declarationName = ts.declarationNameToString(name);
+            var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                var suggestionName = symbolToString(suggestion);
+                var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
+                }
+            }
+            else {
+                if ((_a = moduleSymbol.exports) === null || _a === void 0 ? void 0 : _a.has("default" /* InternalSymbolName.Default */)) {
+                    error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
         function reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName) {
             var _a, _b;
             var localSymbol = (_b = (_a = moduleSymbol.valueDeclaration) === null || _a === void 0 ? void 0 : _a.locals) === null || _b === void 0 ? void 0 : _b.get(name.escapedText);
@@ -51407,6 +51431,13 @@ var ts;
             }
         }
         function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            if (ts.isImportSpecifier(node) && ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             var root = ts.isBindingElement(node) ? ts.getRootDeclaration(node) : node.parent.parent.parent;
             var commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             var resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -51428,6 +51459,13 @@ var ts;
             return resolved;
         }
         function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            if (ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             var resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
@@ -62378,7 +62416,7 @@ var ts;
                 return includes & 8388608 /* TypeFlags.IncludesWildcard */ ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & 98304 /* TypeFlags.Nullable */) {
-                return includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
+                return includes & 16777216 /* TypeFlags.IncludesEmptyObject */ ? neverType : includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
             }
             if (includes & 4 /* TypeFlags.String */ && includes & (128 /* TypeFlags.StringLiteral */ | 134217728 /* TypeFlags.TemplateLiteral */ | 268435456 /* TypeFlags.StringMapping */) ||
                 includes & 8 /* TypeFlags.Number */ && includes & 256 /* TypeFlags.NumberLiteral */ ||
@@ -63068,7 +63106,7 @@ var ts;
             // (T | U)[K] -> T[K] | U[K] (reading)
             // (T | U)[K] -> T[K] & U[K] (writing)
             // (T & U)[K] -> T[K] & U[K]
-            if (objectType.flags & 3145728 /* TypeFlags.UnionOrIntersection */) {
+            if (objectType.flags & 1048576 /* TypeFlags.Union */ || objectType.flags & 2097152 /* TypeFlags.Intersection */ && !shouldDeferIndexType(objectType)) {
                 var types = ts.map(objectType.types, function (t) { return getSimplifiedType(getIndexedAccessType(t, indexType), writing); });
                 return objectType.flags & 2097152 /* TypeFlags.Intersection */ || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -65476,7 +65514,7 @@ var ts;
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & 2097152 /* TypeFlags.Intersection */) {
+            if (type.flags & 2097152 /* TypeFlags.Intersection */ && ts.some(type.types, isEmptyAnonymousObjectType)) {
                 var normalizedTypes = ts.sameMap(type.types, function (t) { return getNormalizedType(t, writing); });
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -66647,7 +66685,7 @@ var ts;
                                     // create a new chain for the constraint error
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors, /* headMessage */ undefined, intersectionState)) {
                                     return result;
                                 }
                                 // prefer the shorter chain of the constraint comparison chain, and the direct comparison chain
@@ -66739,8 +66777,8 @@ var ts;
                         var skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         var skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
                         // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false)) {
-                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false);
+                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState)) {
+                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -71769,7 +71807,7 @@ var ts;
                 var narrowedPropType = narrowType(propType);
                 return filterType(type, function (t) {
                     var discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
             function narrowTypeByDiscriminantProperty(type, access, operator, value, assumeTrue) {
@@ -71818,7 +71856,7 @@ var ts;
             }
             function narrowByInKeyword(type, name, assumeTrue) {
                 if (type.flags & 1048576 /* TypeFlags.Union */
-                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type
+                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || ts.isThisTypeParameter(type)
                     || type.flags & 2097152 /* TypeFlags.Intersection */ && ts.every(type.types, function (t) { return t.symbol !== globalThisSymbol; })) {
                     return filterType(type, function (t) { return isTypePresencePossible(t, name, assumeTrue); });
@@ -71951,14 +71989,18 @@ var ts;
                     assumeTrue = !assumeTrue;
                 }
                 var valueType = getTypeOfExpression(value);
-                if ((type.flags & 2 /* TypeFlags.Unknown */) && assumeTrue && (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
+                if (((type.flags & 2 /* TypeFlags.Unknown */) || isEmptyAnonymousObjectType(type) && !(valueType.flags & 98304 /* TypeFlags.Nullable */)) &&
+                    assumeTrue &&
+                    (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
                     if (valueType.flags & (131068 /* TypeFlags.Primitive */ | 67108864 /* TypeFlags.NonPrimitive */)) {
                         return valueType;
                     }
                     if (valueType.flags & 524288 /* TypeFlags.Object */) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & 2 /* TypeFlags.Unknown */) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & 98304 /* TypeFlags.Nullable */) {
                     if (!strictNullChecks) {
@@ -72417,7 +72459,9 @@ var ts;
                 !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && getBaseConstraintOrType(type).flags & (98304 /* TypeFlags.Nullable */ | 1048576 /* TypeFlags.Union */));
         }
         function isGenericTypeWithoutNullableConstraint(type) {
-            return !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
+            return type.flags & 2097152 /* TypeFlags.Intersection */ ?
+                ts.some(type.types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
         }
         function hasContextualTypeWithNoGenericTypes(node, checkMode) {
             // Computing the contextual type for a child of a JSX element involves resolving the type of the
@@ -127114,9 +127158,7 @@ var ts;
                 }
             }
         }
-        var seenRefs = buildInfoPath ? new ts.Set() : undefined;
         var buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs === null || seenRefs === void 0 ? void 0 : seenRefs.add(resolvedPath);
         /** Inputs are up-to-date, just need either timestamp update or bundle prepend manipulation to make it look up-to-date */
         var pseudoUpToDate = false;
         var usesPrepend = false;
@@ -127131,7 +127173,7 @@ var ts;
                     continue;
                 }
                 // Check if tsbuildinfo path is shared, then we need to rebuild
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: ts.UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath,
@@ -127189,25 +127231,9 @@ var ts;
             oldestOutputFileName: oldestOutputFileName
         };
     }
-    function hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath) {
-        if (seenRefs.has(resolvedRefPath))
-            return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath) {
         var refBuildInfo = state.buildInfoCache.get(resolvedRefPath);
-        if (refBuildInfo.path === buildInfoCacheEntry.path)
-            return true;
-        if (resolvedConfig.projectReferences) {
-            // Check references
-            for (var _i = 0, _a = resolvedConfig.projectReferences; _i < _a.length; _i++) {
-                var ref = _a[_i];
-                var resolvedRef = ts.resolveProjectReferencePath(ref);
-                var resolvedRefPath_1 = toResolvedConfigFilePath(state, resolvedRef);
-                var resolvedConfig_1 = parseConfigFile(state, resolvedRef, resolvedRefPath_1);
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig_1, resolvedRefPath_1))
-                    return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
     function getUpToDateStatus(state, project, resolvedPath) {
         if (project === undefined) {
diff --git a/lib/typescriptServices.js b/lib/typescriptServices.js
index 9e45164b7c4c9..61b1259b561f8 100644
--- a/lib/typescriptServices.js
+++ b/lib/typescriptServices.js
@@ -294,7 +294,7 @@ var ts;
     // The following is baselined as a literal template type without intervention
     /** The version of the TypeScript compiler release */
     // eslint-disable-next-line @typescript-eslint/no-inferrable-types
-    ts.version = "4.8.2";
+    ts.version = "4.8.3";
     /* @internal */
     var Comparison;
     (function (Comparison) {
@@ -9060,7 +9060,7 @@ var ts;
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashnode_and_then_add_node_to_the_types_field_in_your_tsconfig: diag(2591, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashno_2591", "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i --save-dev @types/node` and then add 'node' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slashjquery_and_then_add_jquery_to_the_types_field_in_your_tsconfig: diag(2592, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slash_2592", "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i --save-dev @types/jquery` and then add 'jquery' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_types_Slashjest_or_npm_i_save_dev_types_Slashmocha_and_then_add_jest_or_mocha_to_the_types_field_in_your_tsconfig: diag(2593, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_type_2593", "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i --save-dev @types/jest` or `npm i --save-dev @types/mocha` and then add 'jest' or 'mocha' to the types field in your tsconfig."),
-        This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the__2594", "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag."),
+        This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag_2594", "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag."),
         _0_can_only_be_imported_by_using_a_default_import: diag(2595, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_default_import_2595", "'{0}' can only be imported by using a default import."),
         _0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import: diag(2596, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import_2596", "'{0}' can only be imported by turning on the 'esModuleInterop' flag and using a default import."),
         _0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import: diag(2597, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import_2597", "'{0}' can only be imported by using a 'require' call or by using a default import."),
@@ -44821,7 +44821,7 @@ var ts;
                 var _a, _b;
                 if (path === undefined)
                     return path;
-                return ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames })(ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a)));
+                return ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a));
             }
             function combineDirectoryPath(root, dir) {
                 return ts.ensureTrailingDirectorySeparator(ts.combinePaths(root, dir));
@@ -44841,7 +44841,7 @@ var ts;
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? ts.startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)) {
+                    && (state.compilerOptions.configFile ? ts.containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)) {
                     // So that all means we'll only try these guesses for files outside `node_modules` in a directory where the `package.json` and `tsconfig.json` are siblings.
                     // Even with all that, we still don't know if the root of the output file structure will be (relative to the package file)
                     // `.`, `./src` or any other deeper directory structure. (If project references are used, it's definitely `.` by fiat, so that should be pretty common.)
@@ -44897,7 +44897,7 @@ var ts;
                         var candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (var _e = 0, candidateDirectories_1 = candidateDirectories; _e < candidateDirectories_1.length; _e++) {
                             var candidateDir = candidateDirectories_1[_e];
-                            if (ts.startsWith(finalPath, candidateDir)) {
+                            if (ts.containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 // The matched export is looking up something in either the out declaration or js dir, now map the written path back into the source dir and source extension
                                 var pathFragment = finalPath.slice(candidateDir.length + 1); // +1 to also remove directory seperator
                                 var possibleInputBase = ts.combinePaths(commonSourceDirGuess, pathFragment);
@@ -51179,41 +51179,61 @@ var ts;
             return typeof file.externalModuleIndicator !== "object" && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), /*sourceNode*/ undefined, dontResolveAlias);
         }
         function getTargetOfImportClause(node, dontResolveAlias) {
-            var _a;
             var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                var exportDefaultSymbol = void 0;
-                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
-                }
-                var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
-                var hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
-                        var exportAssignment = exportEqualsSymbol.valueDeclaration;
-                        var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-                        if (exportAssignment) {
-                            ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+        function getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias) {
+            var _a;
+            var exportDefaultSymbol;
+            if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
+            }
+            var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
+            var specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            var hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
+                    var exportAssignment = exportEqualsSymbol.valueDeclaration;
+                    var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+                    if (exportAssignment) {
+                        ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
-                    var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
-                    return resolved;
+                else if (ts.isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
-                return exportDefaultSymbol;
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, ts.isImportOrExportSpecifier(node) && node.propertyName || node.name);
+                }
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
+            return exportDefaultSymbol;
+        }
+        function getModuleSpecifierForImportOrExport(node) {
+            switch (node.kind) {
+                case 267 /* SyntaxKind.ImportClause */: return node.parent.moduleSpecifier;
+                case 265 /* SyntaxKind.ImportEqualsDeclaration */: return ts.isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case 268 /* SyntaxKind.NamespaceImport */: return node.parent.parent.moduleSpecifier;
+                case 270 /* SyntaxKind.ImportSpecifier */: return node.parent.parent.parent.moduleSpecifier;
+                case 275 /* SyntaxKind.ExportSpecifier */: return node.parent.parent.moduleSpecifier;
+                default: return ts.Debug.assertNever(node);
             }
         }
         function reportNonDefaultExport(moduleSymbol, node) {
@@ -51303,7 +51323,7 @@ var ts;
             }
         }
         function getExternalModuleMember(node, specifier, dontResolveAlias) {
-            var _a, _b;
+            var _a;
             if (dontResolveAlias === void 0) { dontResolveAlias = false; }
             var moduleSpecifier = ts.getExternalModuleRequireArgument(node) || node.moduleSpecifier;
             var moduleSymbol = resolveExternalModuleName(node, moduleSpecifier); // TODO: GH#18217
@@ -51339,29 +51359,33 @@ var ts;
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        var moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        var declarationName = ts.declarationNameToString(name);
-                        var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            var suggestionName = symbolToString(suggestion);
-                            var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
-                            }
-                        }
-                        else {
-                            if ((_b = moduleSymbol.exports) === null || _b === void 0 ? void 0 : _b.has("default" /* InternalSymbolName.Default */)) {
-                                error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
+        function errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name) {
+            var _a;
+            var moduleName = getFullyQualifiedName(moduleSymbol, node);
+            var declarationName = ts.declarationNameToString(name);
+            var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                var suggestionName = symbolToString(suggestion);
+                var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
+                }
+            }
+            else {
+                if ((_a = moduleSymbol.exports) === null || _a === void 0 ? void 0 : _a.has("default" /* InternalSymbolName.Default */)) {
+                    error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
         function reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName) {
             var _a, _b;
             var localSymbol = (_b = (_a = moduleSymbol.valueDeclaration) === null || _a === void 0 ? void 0 : _a.locals) === null || _b === void 0 ? void 0 : _b.get(name.escapedText);
@@ -51407,6 +51431,13 @@ var ts;
             }
         }
         function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            if (ts.isImportSpecifier(node) && ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             var root = ts.isBindingElement(node) ? ts.getRootDeclaration(node) : node.parent.parent.parent;
             var commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             var resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -51428,6 +51459,13 @@ var ts;
             return resolved;
         }
         function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            if (ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             var resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
@@ -62378,7 +62416,7 @@ var ts;
                 return includes & 8388608 /* TypeFlags.IncludesWildcard */ ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & 98304 /* TypeFlags.Nullable */) {
-                return includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
+                return includes & 16777216 /* TypeFlags.IncludesEmptyObject */ ? neverType : includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
             }
             if (includes & 4 /* TypeFlags.String */ && includes & (128 /* TypeFlags.StringLiteral */ | 134217728 /* TypeFlags.TemplateLiteral */ | 268435456 /* TypeFlags.StringMapping */) ||
                 includes & 8 /* TypeFlags.Number */ && includes & 256 /* TypeFlags.NumberLiteral */ ||
@@ -63068,7 +63106,7 @@ var ts;
             // (T | U)[K] -> T[K] | U[K] (reading)
             // (T | U)[K] -> T[K] & U[K] (writing)
             // (T & U)[K] -> T[K] & U[K]
-            if (objectType.flags & 3145728 /* TypeFlags.UnionOrIntersection */) {
+            if (objectType.flags & 1048576 /* TypeFlags.Union */ || objectType.flags & 2097152 /* TypeFlags.Intersection */ && !shouldDeferIndexType(objectType)) {
                 var types = ts.map(objectType.types, function (t) { return getSimplifiedType(getIndexedAccessType(t, indexType), writing); });
                 return objectType.flags & 2097152 /* TypeFlags.Intersection */ || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -65476,7 +65514,7 @@ var ts;
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & 2097152 /* TypeFlags.Intersection */) {
+            if (type.flags & 2097152 /* TypeFlags.Intersection */ && ts.some(type.types, isEmptyAnonymousObjectType)) {
                 var normalizedTypes = ts.sameMap(type.types, function (t) { return getNormalizedType(t, writing); });
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -66647,7 +66685,7 @@ var ts;
                                     // create a new chain for the constraint error
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors, /* headMessage */ undefined, intersectionState)) {
                                     return result;
                                 }
                                 // prefer the shorter chain of the constraint comparison chain, and the direct comparison chain
@@ -66739,8 +66777,8 @@ var ts;
                         var skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         var skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
                         // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false)) {
-                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false);
+                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState)) {
+                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -71769,7 +71807,7 @@ var ts;
                 var narrowedPropType = narrowType(propType);
                 return filterType(type, function (t) {
                     var discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
             function narrowTypeByDiscriminantProperty(type, access, operator, value, assumeTrue) {
@@ -71818,7 +71856,7 @@ var ts;
             }
             function narrowByInKeyword(type, name, assumeTrue) {
                 if (type.flags & 1048576 /* TypeFlags.Union */
-                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type
+                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || ts.isThisTypeParameter(type)
                     || type.flags & 2097152 /* TypeFlags.Intersection */ && ts.every(type.types, function (t) { return t.symbol !== globalThisSymbol; })) {
                     return filterType(type, function (t) { return isTypePresencePossible(t, name, assumeTrue); });
@@ -71951,14 +71989,18 @@ var ts;
                     assumeTrue = !assumeTrue;
                 }
                 var valueType = getTypeOfExpression(value);
-                if ((type.flags & 2 /* TypeFlags.Unknown */) && assumeTrue && (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
+                if (((type.flags & 2 /* TypeFlags.Unknown */) || isEmptyAnonymousObjectType(type) && !(valueType.flags & 98304 /* TypeFlags.Nullable */)) &&
+                    assumeTrue &&
+                    (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
                     if (valueType.flags & (131068 /* TypeFlags.Primitive */ | 67108864 /* TypeFlags.NonPrimitive */)) {
                         return valueType;
                     }
                     if (valueType.flags & 524288 /* TypeFlags.Object */) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & 2 /* TypeFlags.Unknown */) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & 98304 /* TypeFlags.Nullable */) {
                     if (!strictNullChecks) {
@@ -72417,7 +72459,9 @@ var ts;
                 !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && getBaseConstraintOrType(type).flags & (98304 /* TypeFlags.Nullable */ | 1048576 /* TypeFlags.Union */));
         }
         function isGenericTypeWithoutNullableConstraint(type) {
-            return !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
+            return type.flags & 2097152 /* TypeFlags.Intersection */ ?
+                ts.some(type.types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
         }
         function hasContextualTypeWithNoGenericTypes(node, checkMode) {
             // Computing the contextual type for a child of a JSX element involves resolving the type of the
@@ -127114,9 +127158,7 @@ var ts;
                 }
             }
         }
-        var seenRefs = buildInfoPath ? new ts.Set() : undefined;
         var buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs === null || seenRefs === void 0 ? void 0 : seenRefs.add(resolvedPath);
         /** Inputs are up-to-date, just need either timestamp update or bundle prepend manipulation to make it look up-to-date */
         var pseudoUpToDate = false;
         var usesPrepend = false;
@@ -127131,7 +127173,7 @@ var ts;
                     continue;
                 }
                 // Check if tsbuildinfo path is shared, then we need to rebuild
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: ts.UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath,
@@ -127189,25 +127231,9 @@ var ts;
             oldestOutputFileName: oldestOutputFileName
         };
     }
-    function hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath) {
-        if (seenRefs.has(resolvedRefPath))
-            return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath) {
         var refBuildInfo = state.buildInfoCache.get(resolvedRefPath);
-        if (refBuildInfo.path === buildInfoCacheEntry.path)
-            return true;
-        if (resolvedConfig.projectReferences) {
-            // Check references
-            for (var _i = 0, _a = resolvedConfig.projectReferences; _i < _a.length; _i++) {
-                var ref = _a[_i];
-                var resolvedRef = ts.resolveProjectReferencePath(ref);
-                var resolvedRefPath_1 = toResolvedConfigFilePath(state, resolvedRef);
-                var resolvedConfig_1 = parseConfigFile(state, resolvedRef, resolvedRefPath_1);
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig_1, resolvedRefPath_1))
-                    return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
     function getUpToDateStatus(state, project, resolvedPath) {
         if (project === undefined) {
diff --git a/lib/typingsInstaller.js b/lib/typingsInstaller.js
index 8ab14c8266cf2..9303e787c1ef4 100644
--- a/lib/typingsInstaller.js
+++ b/lib/typingsInstaller.js
@@ -89,7 +89,7 @@ var ts;
     // The following is baselined as a literal template type without intervention
     /** The version of the TypeScript compiler release */
     // eslint-disable-next-line @typescript-eslint/no-inferrable-types
-    ts.version = "4.8.2";
+    ts.version = "4.8.3";
     /* @internal */
     var Comparison;
     (function (Comparison) {
@@ -8855,7 +8855,7 @@ var ts;
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashnode_and_then_add_node_to_the_types_field_in_your_tsconfig: diag(2591, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_node_Try_npm_i_save_dev_types_Slashno_2591", "Cannot find name '{0}'. Do you need to install type definitions for node? Try `npm i --save-dev @types/node` and then add 'node' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slashjquery_and_then_add_jquery_to_the_types_field_in_your_tsconfig: diag(2592, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_jQuery_Try_npm_i_save_dev_types_Slash_2592", "Cannot find name '{0}'. Do you need to install type definitions for jQuery? Try `npm i --save-dev @types/jquery` and then add 'jquery' to the types field in your tsconfig."),
         Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_types_Slashjest_or_npm_i_save_dev_types_Slashmocha_and_then_add_jest_or_mocha_to_the_types_field_in_your_tsconfig: diag(2593, ts.DiagnosticCategory.Error, "Cannot_find_name_0_Do_you_need_to_install_type_definitions_for_a_test_runner_Try_npm_i_save_dev_type_2593", "Cannot find name '{0}'. Do you need to install type definitions for a test runner? Try `npm i --save-dev @types/jest` or `npm i --save-dev @types/mocha` and then add 'jest' or 'mocha' to the types field in your tsconfig."),
-        This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the__2594", "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag."),
+        This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag: diag(2594, ts.DiagnosticCategory.Error, "This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag_2594", "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag."),
         _0_can_only_be_imported_by_using_a_default_import: diag(2595, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_default_import_2595", "'{0}' can only be imported by using a default import."),
         _0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import: diag(2596, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import_2596", "'{0}' can only be imported by turning on the 'esModuleInterop' flag and using a default import."),
         _0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import: diag(2597, ts.DiagnosticCategory.Error, "_0_can_only_be_imported_by_using_a_require_call_or_by_using_a_default_import_2597", "'{0}' can only be imported by using a 'require' call or by using a default import."),
@@ -44616,7 +44616,7 @@ var ts;
                 var _a, _b;
                 if (path === undefined)
                     return path;
-                return ts.hostGetCanonicalFileName({ useCaseSensitiveFileNames: useCaseSensitiveFileNames })(ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a)));
+                return ts.getNormalizedAbsolutePath(path, (_b = (_a = state.host).getCurrentDirectory) === null || _b === void 0 ? void 0 : _b.call(_a));
             }
             function combineDirectoryPath(root, dir) {
                 return ts.ensureTrailingDirectorySeparator(ts.combinePaths(root, dir));
@@ -44636,7 +44636,7 @@ var ts;
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? ts.startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)) {
+                    && (state.compilerOptions.configFile ? ts.containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)) {
                     // So that all means we'll only try these guesses for files outside `node_modules` in a directory where the `package.json` and `tsconfig.json` are siblings.
                     // Even with all that, we still don't know if the root of the output file structure will be (relative to the package file)
                     // `.`, `./src` or any other deeper directory structure. (If project references are used, it's definitely `.` by fiat, so that should be pretty common.)
@@ -44692,7 +44692,7 @@ var ts;
                         var candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (var _e = 0, candidateDirectories_1 = candidateDirectories; _e < candidateDirectories_1.length; _e++) {
                             var candidateDir = candidateDirectories_1[_e];
-                            if (ts.startsWith(finalPath, candidateDir)) {
+                            if (ts.containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 // The matched export is looking up something in either the out declaration or js dir, now map the written path back into the source dir and source extension
                                 var pathFragment = finalPath.slice(candidateDir.length + 1); // +1 to also remove directory seperator
                                 var possibleInputBase = ts.combinePaths(commonSourceDirGuess, pathFragment);
@@ -50974,41 +50974,61 @@ var ts;
             return typeof file.externalModuleIndicator !== "object" && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), /*sourceNode*/ undefined, dontResolveAlias);
         }
         function getTargetOfImportClause(node, dontResolveAlias) {
-            var _a;
             var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                var exportDefaultSymbol = void 0;
-                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
-                }
-                var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
-                var hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
-                        var exportAssignment = exportEqualsSymbol.valueDeclaration;
-                        var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-                        if (exportAssignment) {
-                            ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+        function getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias) {
+            var _a;
+            var exportDefaultSymbol;
+            if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* InternalSymbolName.Default */, node, dontResolveAlias);
+            }
+            var file = (_a = moduleSymbol.declarations) === null || _a === void 0 ? void 0 : _a.find(ts.isSourceFile);
+            var specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            var hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    var compilerOptionName = moduleKind >= ts.ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    var exportEqualsSymbol = moduleSymbol.exports.get("export=" /* InternalSymbolName.ExportEquals */);
+                    var exportAssignment = exportEqualsSymbol.valueDeclaration;
+                    var err = error(node.name, ts.Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+                    if (exportAssignment) {
+                        ts.addRelatedInfo(err, ts.createDiagnosticForNode(exportAssignment, ts.Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag, compilerOptionName));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
-                    var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
-                    return resolved;
+                else if (ts.isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
+                }
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, ts.isImportOrExportSpecifier(node) && node.propertyName || node.name);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
-                return exportDefaultSymbol;
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                var resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
+            return exportDefaultSymbol;
+        }
+        function getModuleSpecifierForImportOrExport(node) {
+            switch (node.kind) {
+                case 267 /* SyntaxKind.ImportClause */: return node.parent.moduleSpecifier;
+                case 265 /* SyntaxKind.ImportEqualsDeclaration */: return ts.isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case 268 /* SyntaxKind.NamespaceImport */: return node.parent.parent.moduleSpecifier;
+                case 270 /* SyntaxKind.ImportSpecifier */: return node.parent.parent.parent.moduleSpecifier;
+                case 275 /* SyntaxKind.ExportSpecifier */: return node.parent.parent.moduleSpecifier;
+                default: return ts.Debug.assertNever(node);
             }
         }
         function reportNonDefaultExport(moduleSymbol, node) {
@@ -51098,7 +51118,7 @@ var ts;
             }
         }
         function getExternalModuleMember(node, specifier, dontResolveAlias) {
-            var _a, _b;
+            var _a;
             if (dontResolveAlias === void 0) { dontResolveAlias = false; }
             var moduleSpecifier = ts.getExternalModuleRequireArgument(node) || node.moduleSpecifier;
             var moduleSymbol = resolveExternalModuleName(node, moduleSpecifier); // TODO: GH#18217
@@ -51134,29 +51154,33 @@ var ts;
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        var moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        var declarationName = ts.declarationNameToString(name);
-                        var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            var suggestionName = symbolToString(suggestion);
-                            var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
-                            }
-                        }
-                        else {
-                            if ((_b = moduleSymbol.exports) === null || _b === void 0 ? void 0 : _b.has("default" /* InternalSymbolName.Default */)) {
-                                error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
+        function errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name) {
+            var _a;
+            var moduleName = getFullyQualifiedName(moduleSymbol, node);
+            var declarationName = ts.declarationNameToString(name);
+            var suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                var suggestionName = symbolToString(suggestion);
+                var diagnostic = error(name, ts.Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    ts.addRelatedInfo(diagnostic, ts.createDiagnosticForNode(suggestion.valueDeclaration, ts.Diagnostics._0_is_declared_here, suggestionName));
+                }
+            }
+            else {
+                if ((_a = moduleSymbol.exports) === null || _a === void 0 ? void 0 : _a.has("default" /* InternalSymbolName.Default */)) {
+                    error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead, moduleName, declarationName);
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
         function reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName) {
             var _a, _b;
             var localSymbol = (_b = (_a = moduleSymbol.valueDeclaration) === null || _a === void 0 ? void 0 : _a.locals) === null || _b === void 0 ? void 0 : _b.get(name.escapedText);
@@ -51202,6 +51226,13 @@ var ts;
             }
         }
         function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            if (ts.isImportSpecifier(node) && ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             var root = ts.isBindingElement(node) ? ts.getRootDeclaration(node) : node.parent.parent.parent;
             var commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             var resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -51223,6 +51254,13 @@ var ts;
             return resolved;
         }
         function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            if (ts.idText(node.propertyName || node.name) === "default" /* InternalSymbolName.Default */) {
+                var specifier = getModuleSpecifierForImportOrExport(node);
+                var moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             var resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
@@ -62173,7 +62211,7 @@ var ts;
                 return includes & 8388608 /* TypeFlags.IncludesWildcard */ ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & 98304 /* TypeFlags.Nullable */) {
-                return includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
+                return includes & 16777216 /* TypeFlags.IncludesEmptyObject */ ? neverType : includes & 32768 /* TypeFlags.Undefined */ ? undefinedType : nullType;
             }
             if (includes & 4 /* TypeFlags.String */ && includes & (128 /* TypeFlags.StringLiteral */ | 134217728 /* TypeFlags.TemplateLiteral */ | 268435456 /* TypeFlags.StringMapping */) ||
                 includes & 8 /* TypeFlags.Number */ && includes & 256 /* TypeFlags.NumberLiteral */ ||
@@ -62863,7 +62901,7 @@ var ts;
             // (T | U)[K] -> T[K] | U[K] (reading)
             // (T | U)[K] -> T[K] & U[K] (writing)
             // (T & U)[K] -> T[K] & U[K]
-            if (objectType.flags & 3145728 /* TypeFlags.UnionOrIntersection */) {
+            if (objectType.flags & 1048576 /* TypeFlags.Union */ || objectType.flags & 2097152 /* TypeFlags.Intersection */ && !shouldDeferIndexType(objectType)) {
                 var types = ts.map(objectType.types, function (t) { return getSimplifiedType(getIndexedAccessType(t, indexType), writing); });
                 return objectType.flags & 2097152 /* TypeFlags.Intersection */ || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -65271,7 +65309,7 @@ var ts;
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & 2097152 /* TypeFlags.Intersection */) {
+            if (type.flags & 2097152 /* TypeFlags.Intersection */ && ts.some(type.types, isEmptyAnonymousObjectType)) {
                 var normalizedTypes = ts.sameMap(type.types, function (t) { return getNormalizedType(t, writing); });
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -66442,7 +66480,7 @@ var ts;
                                     // create a new chain for the constraint error
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, 2 /* RecursionFlags.Target */, reportErrors, /* headMessage */ undefined, intersectionState)) {
                                     return result;
                                 }
                                 // prefer the shorter chain of the constraint comparison chain, and the direct comparison chain
@@ -66534,8 +66572,8 @@ var ts;
                         var skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         var skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
                         // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false)) {
-                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false);
+                        if (result = skipTrue ? -1 /* Ternary.True */ : isRelatedTo(source, getTrueTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState)) {
+                            result &= skipFalse ? -1 /* Ternary.True */ : isRelatedTo(source, getFalseTypeFromConditionalType(c), 2 /* RecursionFlags.Target */, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -71564,7 +71602,7 @@ var ts;
                 var narrowedPropType = narrowType(propType);
                 return filterType(type, function (t) {
                     var discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & 131072 /* TypeFlags.Never */) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
             function narrowTypeByDiscriminantProperty(type, access, operator, value, assumeTrue) {
@@ -71613,7 +71651,7 @@ var ts;
             }
             function narrowByInKeyword(type, name, assumeTrue) {
                 if (type.flags & 1048576 /* TypeFlags.Union */
-                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type
+                    || type.flags & 524288 /* TypeFlags.Object */ && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || ts.isThisTypeParameter(type)
                     || type.flags & 2097152 /* TypeFlags.Intersection */ && ts.every(type.types, function (t) { return t.symbol !== globalThisSymbol; })) {
                     return filterType(type, function (t) { return isTypePresencePossible(t, name, assumeTrue); });
@@ -71746,14 +71784,18 @@ var ts;
                     assumeTrue = !assumeTrue;
                 }
                 var valueType = getTypeOfExpression(value);
-                if ((type.flags & 2 /* TypeFlags.Unknown */) && assumeTrue && (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
+                if (((type.flags & 2 /* TypeFlags.Unknown */) || isEmptyAnonymousObjectType(type) && !(valueType.flags & 98304 /* TypeFlags.Nullable */)) &&
+                    assumeTrue &&
+                    (operator === 36 /* SyntaxKind.EqualsEqualsEqualsToken */ || operator === 37 /* SyntaxKind.ExclamationEqualsEqualsToken */)) {
                     if (valueType.flags & (131068 /* TypeFlags.Primitive */ | 67108864 /* TypeFlags.NonPrimitive */)) {
                         return valueType;
                     }
                     if (valueType.flags & 524288 /* TypeFlags.Object */) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & 2 /* TypeFlags.Unknown */) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & 98304 /* TypeFlags.Nullable */) {
                     if (!strictNullChecks) {
@@ -72212,7 +72254,9 @@ var ts;
                 !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && getBaseConstraintOrType(type).flags & (98304 /* TypeFlags.Nullable */ | 1048576 /* TypeFlags.Union */));
         }
         function isGenericTypeWithoutNullableConstraint(type) {
-            return !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
+            return type.flags & 2097152 /* TypeFlags.Intersection */ ?
+                ts.some(type.types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & 465829888 /* TypeFlags.Instantiable */ && !maybeTypeOfKind(getBaseConstraintOrType(type), 98304 /* TypeFlags.Nullable */));
         }
         function hasContextualTypeWithNoGenericTypes(node, checkMode) {
             // Computing the contextual type for a child of a JSX element involves resolving the type of the
@@ -126909,9 +126953,7 @@ var ts;
                 }
             }
         }
-        var seenRefs = buildInfoPath ? new ts.Set() : undefined;
         var buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs === null || seenRefs === void 0 ? void 0 : seenRefs.add(resolvedPath);
         /** Inputs are up-to-date, just need either timestamp update or bundle prepend manipulation to make it look up-to-date */
         var pseudoUpToDate = false;
         var usesPrepend = false;
@@ -126926,7 +126968,7 @@ var ts;
                     continue;
                 }
                 // Check if tsbuildinfo path is shared, then we need to rebuild
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: ts.UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath,
@@ -126984,25 +127026,9 @@ var ts;
             oldestOutputFileName: oldestOutputFileName
         };
     }
-    function hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath) {
-        if (seenRefs.has(resolvedRefPath))
-            return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath) {
         var refBuildInfo = state.buildInfoCache.get(resolvedRefPath);
-        if (refBuildInfo.path === buildInfoCacheEntry.path)
-            return true;
-        if (resolvedConfig.projectReferences) {
-            // Check references
-            for (var _i = 0, _a = resolvedConfig.projectReferences; _i < _a.length; _i++) {
-                var ref = _a[_i];
-                var resolvedRef = ts.resolveProjectReferencePath(ref);
-                var resolvedRefPath_1 = toResolvedConfigFilePath(state, resolvedRef);
-                var resolvedConfig_1 = parseConfigFile(state, resolvedRef, resolvedRefPath_1);
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig_1, resolvedRefPath_1))
-                    return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
     function getUpToDateStatus(state, project, resolvedPath) {
         if (project === undefined) {
diff --git a/package.json b/package.json
index b3d43e3a0337c..759cfbc32d810 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
     "name": "typescript",
     "author": "Microsoft Corp.",
     "homepage": "https://www.typescriptlang.org/",
-    "version": "4.8.2",
+    "version": "4.8.3",
     "license": "Apache-2.0",
     "description": "TypeScript is a language for application scale JavaScript development",
     "keywords": [
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 15f384699f09f..194f51256860b 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -2798,44 +2798,66 @@ namespace ts {
         function getTargetOfImportClause(node: ImportClause, dontResolveAlias: boolean): Symbol | undefined {
             const moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
             if (moduleSymbol) {
-                let exportDefaultSymbol: Symbol | undefined;
-                if (isShorthandAmbientModuleSymbol(moduleSymbol)) {
-                    exportDefaultSymbol = moduleSymbol;
-                }
-                else {
-                    exportDefaultSymbol = resolveExportByName(moduleSymbol, InternalSymbolName.Default, node, dontResolveAlias);
-                }
-
-                const file = moduleSymbol.declarations?.find(isSourceFile);
-                const hasDefaultOnly = isOnlyImportedAsDefault(node.parent.moduleSpecifier);
-                const hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, node.parent.moduleSpecifier);
-                if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
-                    if (hasExportAssignmentSymbol(moduleSymbol)) {
-                        const compilerOptionName = moduleKind >= ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
-                        const exportEqualsSymbol = moduleSymbol.exports!.get(InternalSymbolName.ExportEquals);
-                        const exportAssignment = exportEqualsSymbol!.valueDeclaration;
-                        const err = error(node.name, Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
-
-                        if (exportAssignment) {
-                            addRelatedInfo(err, createDiagnosticForNode(
-                                exportAssignment,
-                                Diagnostics.This_module_is_declared_with_using_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag,
-                                compilerOptionName
-                            ));
-                        }
-                    }
-                    else {
-                        reportNonDefaultExport(moduleSymbol, node);
+                return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+            }
+        }
+
+        function getTargetofModuleDefault(moduleSymbol: Symbol, node: ImportClause | ImportOrExportSpecifier, dontResolveAlias: boolean) {
+            let exportDefaultSymbol: Symbol | undefined;
+            if (isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                exportDefaultSymbol = moduleSymbol;
+            }
+            else {
+                exportDefaultSymbol = resolveExportByName(moduleSymbol, InternalSymbolName.Default, node, dontResolveAlias);
+            }
+
+            const file = moduleSymbol.declarations?.find(isSourceFile);
+            const specifier = getModuleSpecifierForImportOrExport(node);
+            if (!specifier) {
+                return exportDefaultSymbol;
+            }
+            const hasDefaultOnly = isOnlyImportedAsDefault(specifier);
+            const hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias, specifier);
+            if (!exportDefaultSymbol && !hasSyntheticDefault && !hasDefaultOnly) {
+                if (hasExportAssignmentSymbol(moduleSymbol)) {
+                    const compilerOptionName = moduleKind >= ModuleKind.ES2015 ? "allowSyntheticDefaultImports" : "esModuleInterop";
+                    const exportEqualsSymbol = moduleSymbol.exports!.get(InternalSymbolName.ExportEquals);
+                    const exportAssignment = exportEqualsSymbol!.valueDeclaration;
+                    const err = error(node.name, Diagnostics.Module_0_can_only_be_default_imported_using_the_1_flag, symbolToString(moduleSymbol), compilerOptionName);
+
+                    if (exportAssignment) {
+                        addRelatedInfo(err, createDiagnosticForNode(
+                            exportAssignment,
+                            Diagnostics.This_module_is_declared_with_export_and_can_only_be_used_with_a_default_import_when_using_the_0_flag,
+                            compilerOptionName
+                        ));
                     }
                 }
-                else if (hasSyntheticDefault || hasDefaultOnly) {
-                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
-                    const resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
-                    markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
-                    return resolved;
+                else if (isImportClause(node)) {
+                    reportNonDefaultExport(moduleSymbol, node);
+                }
+                else {
+                    errorNoModuleMemberSymbol(moduleSymbol, moduleSymbol, node, isImportOrExportSpecifier(node) && node.propertyName || node.name);
                 }
-                markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
-                return exportDefaultSymbol;
+            }
+            else if (hasSyntheticDefault || hasDefaultOnly) {
+                // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                const resolved = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                markSymbolOfAliasDeclarationIfTypeOnly(node, moduleSymbol, resolved, /*overwriteTypeOnly*/ false);
+                return resolved;
+            }
+            markSymbolOfAliasDeclarationIfTypeOnly(node, exportDefaultSymbol, /*finalTarget*/ undefined, /*overwriteTypeOnly*/ false);
+            return exportDefaultSymbol;
+        }
+
+        function getModuleSpecifierForImportOrExport(node: ImportEqualsDeclaration | ImportClause | NamespaceImport | ImportOrExportSpecifier): Expression | undefined {
+            switch (node.kind) {
+                case SyntaxKind.ImportClause: return node.parent.moduleSpecifier;
+                case SyntaxKind.ImportEqualsDeclaration: return isExternalModuleReference(node.moduleReference) ? node.moduleReference.expression : undefined;
+                case SyntaxKind.NamespaceImport: return node.parent.parent.moduleSpecifier;
+                case SyntaxKind.ImportSpecifier: return node.parent.parent.parent.moduleSpecifier;
+                case SyntaxKind.ExportSpecifier: return node.parent.parent.moduleSpecifier;
+                default: return Debug.assertNever(node);
             }
         }
 
@@ -2969,38 +2991,42 @@ namespace ts {
                         combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
                         symbolFromModule || symbolFromVariable;
                     if (!symbol) {
-                        const moduleName = getFullyQualifiedName(moduleSymbol, node);
-                        const declarationName = declarationNameToString(name);
-                        const suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
-                        if (suggestion !== undefined) {
-                            const suggestionName = symbolToString(suggestion);
-                            const diagnostic = error(name, Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
-                            if (suggestion.valueDeclaration) {
-                                addRelatedInfo(diagnostic,
-                                    createDiagnosticForNode(suggestion.valueDeclaration, Diagnostics._0_is_declared_here, suggestionName)
-                                );
-                            }
-                        }
-                        else {
-                            if (moduleSymbol.exports?.has(InternalSymbolName.Default)) {
-                                error(
-                                    name,
-                                    Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead,
-                                    moduleName,
-                                    declarationName
-                                );
-                            }
-                            else {
-                                reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
-                            }
-                        }
+                        errorNoModuleMemberSymbol(moduleSymbol, targetSymbol, node, name);
                     }
                     return symbol;
                 }
             }
         }
 
-        function reportNonExportedMember(node: ImportDeclaration | ExportDeclaration | VariableDeclaration, name: Identifier, declarationName: string, moduleSymbol: Symbol, moduleName: string): void {
+        function errorNoModuleMemberSymbol(moduleSymbol: Symbol, targetSymbol: Symbol, node: Node, name: Identifier) {
+            const moduleName = getFullyQualifiedName(moduleSymbol, node);
+            const declarationName = declarationNameToString(name);
+            const suggestion = getSuggestedSymbolForNonexistentModule(name, targetSymbol);
+            if (suggestion !== undefined) {
+                const suggestionName = symbolToString(suggestion);
+                const diagnostic = error(name, Diagnostics._0_has_no_exported_member_named_1_Did_you_mean_2, moduleName, declarationName, suggestionName);
+                if (suggestion.valueDeclaration) {
+                    addRelatedInfo(diagnostic,
+                        createDiagnosticForNode(suggestion.valueDeclaration, Diagnostics._0_is_declared_here, suggestionName)
+                    );
+                }
+            }
+            else {
+                if (moduleSymbol.exports?.has(InternalSymbolName.Default)) {
+                    error(
+                        name,
+                        Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_to_use_import_1_from_0_instead,
+                        moduleName,
+                        declarationName
+                    );
+                }
+                else {
+                    reportNonExportedMember(node, name, declarationName, moduleSymbol, moduleName);
+                }
+            }
+        }
+
+        function reportNonExportedMember(node: Node, name: Identifier, declarationName: string, moduleSymbol: Symbol, moduleName: string): void {
             const localSymbol = moduleSymbol.valueDeclaration?.locals?.get(name.escapedText);
             const exports = moduleSymbol.exports;
             if (localSymbol) {
@@ -3025,7 +3051,7 @@ namespace ts {
             }
         }
 
-        function reportInvalidImportEqualsExportMember(node: ImportDeclaration | ExportDeclaration | VariableDeclaration, name: Identifier, declarationName: string, moduleName: string) {
+        function reportInvalidImportEqualsExportMember(node: Node, name: Identifier, declarationName: string, moduleName: string) {
             if (moduleKind >= ModuleKind.ES2015) {
                 const message = getESModuleInterop(compilerOptions) ? Diagnostics._0_can_only_be_imported_by_using_a_default_import :
                     Diagnostics._0_can_only_be_imported_by_turning_on_the_esModuleInterop_flag_and_using_a_default_import;
@@ -3046,6 +3072,13 @@ namespace ts {
         }
 
         function getTargetOfImportSpecifier(node: ImportSpecifier | BindingElement, dontResolveAlias: boolean): Symbol | undefined {
+            if (isImportSpecifier(node) && idText(node.propertyName || node.name) === InternalSymbolName.Default) {
+                const specifier = getModuleSpecifierForImportOrExport(node);
+                const moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, dontResolveAlias);
+                }
+            }
             const root = isBindingElement(node) ? getRootDeclaration(node) as VariableDeclaration : node.parent.parent.parent;
             const commonJSPropertyAccess = getCommonJSPropertyAccess(root);
             const resolved = getExternalModuleMember(root, commonJSPropertyAccess || node, dontResolveAlias);
@@ -3070,6 +3103,13 @@ namespace ts {
         }
 
         function getTargetOfExportSpecifier(node: ExportSpecifier, meaning: SymbolFlags, dontResolveAlias?: boolean) {
+            if (idText(node.propertyName || node.name) === InternalSymbolName.Default) {
+                const specifier = getModuleSpecifierForImportOrExport(node);
+                const moduleSymbol = specifier && resolveExternalModuleName(node, specifier);
+                if (moduleSymbol) {
+                    return getTargetofModuleDefault(moduleSymbol, node, !!dontResolveAlias);
+                }
+            }
             const resolved = node.parent.parent.moduleSpecifier ?
                 getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
                 resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
@@ -15094,7 +15134,7 @@ namespace ts {
                 return includes & TypeFlags.IncludesWildcard ? wildcardType : anyType;
             }
             if (!strictNullChecks && includes & TypeFlags.Nullable) {
-                return includes & TypeFlags.Undefined ? undefinedType : nullType;
+                return includes & TypeFlags.IncludesEmptyObject ? neverType : includes & TypeFlags.Undefined ? undefinedType : nullType;
             }
             if (includes & TypeFlags.String && includes & (TypeFlags.StringLiteral | TypeFlags.TemplateLiteral | TypeFlags.StringMapping) ||
                 includes & TypeFlags.Number && includes & TypeFlags.NumberLiteral ||
@@ -15834,7 +15874,7 @@ namespace ts {
             // (T | U)[K] -> T[K] | U[K] (reading)
             // (T | U)[K] -> T[K] & U[K] (writing)
             // (T & U)[K] -> T[K] & U[K]
-            if (objectType.flags & TypeFlags.UnionOrIntersection) {
+            if (objectType.flags & TypeFlags.Union || objectType.flags & TypeFlags.Intersection && !shouldDeferIndexType(objectType)) {
                 const types = map((objectType as UnionOrIntersectionType).types, t => getSimplifiedType(getIndexedAccessType(t, indexType), writing));
                 return objectType.flags & TypeFlags.Intersection || writing ? getIntersectionType(types) : getUnionType(types);
             }
@@ -18425,7 +18465,7 @@ namespace ts {
             if (reduced !== type) {
                 return reduced;
             }
-            if (type.flags & TypeFlags.Intersection) {
+            if (type.flags & TypeFlags.Intersection && some((type as IntersectionType).types, isEmptyAnonymousObjectType)) {
                 const normalizedTypes = sameMap(type.types, t => getNormalizedType(t, writing));
                 if (normalizedTypes !== type.types) {
                     return getIntersectionType(normalizedTypes);
@@ -19654,7 +19694,7 @@ namespace ts {
                                     // create a new chain for the constraint error
                                     resetErrorInfo(saveErrorInfo);
                                 }
-                                if (result = isRelatedTo(source, constraint, RecursionFlags.Target, reportErrors)) {
+                                if (result = isRelatedTo(source, constraint, RecursionFlags.Target, reportErrors, /* headMessage */ undefined, intersectionState)) {
                                     return result;
                                 }
                                 // prefer the shorter chain of the constraint comparison chain, and the direct comparison chain
@@ -19748,8 +19788,8 @@ namespace ts {
                         const skipTrue = !isTypeAssignableTo(getPermissiveInstantiation(c.checkType), getPermissiveInstantiation(c.extendsType));
                         const skipFalse = !skipTrue && isTypeAssignableTo(getRestrictiveInstantiation(c.checkType), getRestrictiveInstantiation(c.extendsType));
                         // TODO: Find a nice way to include potential conditional type breakdowns in error output, if they seem good (they usually don't)
-                        if (result = skipTrue ? Ternary.True : isRelatedTo(source, getTrueTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false)) {
-                            result &= skipFalse ? Ternary.True : isRelatedTo(source, getFalseTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false);
+                        if (result = skipTrue ? Ternary.True : isRelatedTo(source, getTrueTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState)) {
+                            result &= skipFalse ? Ternary.True : isRelatedTo(source, getFalseTypeFromConditionalType(c), RecursionFlags.Target, /*reportErrors*/ false, /*headMessage*/ undefined, intersectionState);
                             if (result) {
                                 return result;
                             }
@@ -25023,7 +25063,7 @@ namespace ts {
                 const narrowedPropType = narrowType(propType);
                 return filterType(type, t => {
                     const discriminantType = getTypeOfPropertyOrIndexSignature(t, propName);
-                    return !(narrowedPropType.flags & TypeFlags.Never) && isTypeComparableTo(narrowedPropType, discriminantType);
+                    return !(narrowedPropType.flags & TypeFlags.Never) && areTypesComparable(narrowedPropType, discriminantType);
                 });
             }
 
@@ -25077,7 +25117,7 @@ namespace ts {
 
             function narrowByInKeyword(type: Type, name: __String, assumeTrue: boolean) {
                 if (type.flags & TypeFlags.Union
-                    || type.flags & TypeFlags.Object && declaredType !== type
+                    || type.flags & TypeFlags.Object && declaredType !== type && !(declaredType === unknownType && isEmptyAnonymousObjectType(type))
                     || isThisTypeParameter(type)
                     || type.flags & TypeFlags.Intersection && every((type as IntersectionType).types, t => t.symbol !== globalThisSymbol)) {
                     return filterType(type, t => isTypePresencePossible(t, name, assumeTrue));
@@ -25215,14 +25255,19 @@ namespace ts {
                     assumeTrue = !assumeTrue;
                 }
                 const valueType = getTypeOfExpression(value);
-                if ((type.flags & TypeFlags.Unknown) && assumeTrue && (operator === SyntaxKind.EqualsEqualsEqualsToken || operator === SyntaxKind.ExclamationEqualsEqualsToken)) {
+                if (((type.flags & TypeFlags.Unknown) || isEmptyAnonymousObjectType(type) && !(valueType.flags & TypeFlags.Nullable)) &&
+                    assumeTrue &&
+                    (operator === SyntaxKind.EqualsEqualsEqualsToken || operator === SyntaxKind.ExclamationEqualsEqualsToken)
+                ) {
                     if (valueType.flags & (TypeFlags.Primitive | TypeFlags.NonPrimitive)) {
                         return valueType;
                     }
                     if (valueType.flags & TypeFlags.Object) {
                         return nonPrimitiveType;
                     }
-                    return type;
+                    if (type.flags & TypeFlags.Unknown) {
+                        return type;
+                    }
                 }
                 if (valueType.flags & TypeFlags.Nullable) {
                     if (!strictNullChecks) {
@@ -25716,8 +25761,10 @@ namespace ts {
                 !!(type.flags & TypeFlags.Instantiable && getBaseConstraintOrType(type).flags & (TypeFlags.Nullable | TypeFlags.Union));
         }
 
-        function isGenericTypeWithoutNullableConstraint(type: Type) {
-            return !!(type.flags & TypeFlags.Instantiable && !maybeTypeOfKind(getBaseConstraintOrType(type), TypeFlags.Nullable));
+        function isGenericTypeWithoutNullableConstraint(type: Type): boolean {
+            return type.flags & TypeFlags.Intersection ?
+                some((type as IntersectionType).types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & TypeFlags.Instantiable && !maybeTypeOfKind(getBaseConstraintOrType(type), TypeFlags.Nullable));
         }
 
         function hasContextualTypeWithNoGenericTypes(node: Node, checkMode: CheckMode | undefined) {
diff --git a/src/compiler/corePublic.ts b/src/compiler/corePublic.ts
index b60043e993308..0abc89d49fdf4 100644
--- a/src/compiler/corePublic.ts
+++ b/src/compiler/corePublic.ts
@@ -5,7 +5,7 @@ namespace ts {
     // The following is baselined as a literal template type without intervention
     /** The version of the TypeScript compiler release */
     // eslint-disable-next-line @typescript-eslint/no-inferrable-types
-    export const version = "4.8.2" as string;
+    export const version = "4.8.3" as string;
 
     /**
      * Type of objects whose values are all of the same type.
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 45e2cde143ca8..daa315562c02c 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2677,7 +2677,7 @@
         "category": "Error",
         "code": 2593
     },
-    "This module is declared with using 'export =', and can only be used with a default import when using the '{0}' flag.": {
+    "This module is declared with 'export =', and can only be used with a default import when using the '{0}' flag.": {
         "category": "Error",
         "code": 2594
     },
diff --git a/src/compiler/moduleNameResolver.ts b/src/compiler/moduleNameResolver.ts
index 3c65e4410bdbd..9e3b15f09580c 100644
--- a/src/compiler/moduleNameResolver.ts
+++ b/src/compiler/moduleNameResolver.ts
@@ -2227,7 +2227,7 @@ namespace ts {
             function toAbsolutePath(path: string | undefined): string | undefined;
             function toAbsolutePath(path: string | undefined): string | undefined {
                 if (path === undefined) return path;
-                return hostGetCanonicalFileName({ useCaseSensitiveFileNames })(getNormalizedAbsolutePath(path, state.host.getCurrentDirectory?.()));
+                return getNormalizedAbsolutePath(path, state.host.getCurrentDirectory?.());
             }
 
             function combineDirectoryPath(root: string, dir: string) {
@@ -2249,7 +2249,7 @@ namespace ts {
                 if ((extensions === Extensions.TypeScript || extensions === Extensions.JavaScript || extensions === Extensions.Json)
                     && (state.compilerOptions.declarationDir || state.compilerOptions.outDir)
                     && finalPath.indexOf("/node_modules/") === -1
-                    && (state.compilerOptions.configFile ? startsWith(toAbsolutePath(state.compilerOptions.configFile.fileName), scope.packageDirectory) : true)
+                    && (state.compilerOptions.configFile ? containsPath(scope.packageDirectory, toAbsolutePath(state.compilerOptions.configFile.fileName), !useCaseSensitiveFileNames()) : true)
                 ) {
                     // So that all means we'll only try these guesses for files outside `node_modules` in a directory where the `package.json` and `tsconfig.json` are siblings.
                     // Even with all that, we still don't know if the root of the output file structure will be (relative to the package file)
@@ -2310,7 +2310,7 @@ namespace ts {
                     for (const commonSourceDirGuess of commonSourceDirGuesses) {
                         const candidateDirectories = getOutputDirectoriesForBaseDirectory(commonSourceDirGuess);
                         for (const candidateDir of candidateDirectories) {
-                            if (startsWith(finalPath, candidateDir)) {
+                            if (containsPath(candidateDir, finalPath, !useCaseSensitiveFileNames())) {
                                 // The matched export is looking up something in either the out declaration or js dir, now map the written path back into the source dir and source extension
                                 const pathFragment = finalPath.slice(candidateDir.length + 1); // +1 to also remove directory seperator
                                 const possibleInputBase = combinePaths(commonSourceDirGuess, pathFragment);
diff --git a/src/compiler/tsbuildPublic.ts b/src/compiler/tsbuildPublic.ts
index 90d00833a9925..476662a93c2e9 100644
--- a/src/compiler/tsbuildPublic.ts
+++ b/src/compiler/tsbuildPublic.ts
@@ -1694,10 +1694,7 @@ namespace ts {
             }
         }
 
-        const seenRefs = buildInfoPath ? new Set<ResolvedConfigFilePath>() : undefined;
         const buildInfoCacheEntry = state.buildInfoCache.get(resolvedPath);
-        seenRefs?.add(resolvedPath);
-
         /** Inputs are up-to-date, just need either timestamp update or bundle prepend manipulation to make it look up-to-date */
         let pseudoUpToDate = false;
         let usesPrepend = false;
@@ -1712,7 +1709,7 @@ namespace ts {
                 }
 
                 // Check if tsbuildinfo path is shared, then we need to rebuild
-                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs!, resolvedConfig, resolvedRefPath)) {
+                if (buildInfoCacheEntry && hasSameBuildInfo(state, buildInfoCacheEntry, resolvedRefPath)) {
                     return {
                         type: UpToDateStatusType.OutOfDateWithUpstream,
                         outOfDateOutputFileName: buildInfoPath!,
@@ -1775,22 +1772,9 @@ namespace ts {
         };
     }
 
-    function hasSameBuildInfo(state: SolutionBuilderState, buildInfoCacheEntry: BuildInfoCacheEntry, seenRefs: Set<ResolvedConfigFilePath>, resolvedConfig: ParsedCommandLine, resolvedRefPath: ResolvedConfigFilePath) {
-        if (seenRefs.has(resolvedRefPath)) return false;
-        seenRefs.add(resolvedRefPath);
+    function hasSameBuildInfo(state: SolutionBuilderState, buildInfoCacheEntry: BuildInfoCacheEntry, resolvedRefPath: ResolvedConfigFilePath) {
         const refBuildInfo = state.buildInfoCache.get(resolvedRefPath)!;
-        if (refBuildInfo.path === buildInfoCacheEntry.path) return true;
-
-        if (resolvedConfig.projectReferences) {
-            // Check references
-            for (const ref of resolvedConfig.projectReferences) {
-                const resolvedRef = resolveProjectReferencePath(ref);
-                const resolvedRefPath = toResolvedConfigFilePath(state, resolvedRef);
-                const resolvedConfig = parseConfigFile(state, resolvedRef, resolvedRefPath)!;
-                if (hasSameBuildInfo(state, buildInfoCacheEntry, seenRefs, resolvedConfig, resolvedRefPath)) return true;
-            }
-        }
-        return false;
+        return refBuildInfo.path === buildInfoCacheEntry.path;
     }
 
     function getUpToDateStatus(state: SolutionBuilderState, project: ParsedCommandLine | undefined, resolvedPath: ResolvedConfigFilePath): UpToDateStatus {
diff --git a/src/server/editorServices.ts b/src/server/editorServices.ts
index c6d1513c0771f..3ab9f02741cc1 100644
--- a/src/server/editorServices.ts
+++ b/src/server/editorServices.ts
@@ -4068,7 +4068,7 @@ namespace ts.server {
 
         /*@internal*/
         requestEnablePlugin(project: Project, pluginConfigEntry: PluginImport, searchPaths: string[], pluginConfigOverrides: Map<any> | undefined) {
-            if (!this.host.importServicePlugin && !this.host.require) {
+            if (!this.host.importPlugin && !this.host.require) {
                 this.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                 return;
             }
@@ -4080,7 +4080,7 @@ namespace ts.server {
             }
 
             // If the host supports dynamic import, begin enabling the plugin asynchronously.
-            if (this.host.importServicePlugin) {
+            if (this.host.importPlugin) {
                 const importPromise = project.beginEnablePluginAsync(pluginConfigEntry, searchPaths, pluginConfigOverrides);
                 this.pendingPluginEnablements ??= new Map();
                 let promises = this.pendingPluginEnablements.get(project);
diff --git a/src/server/project.ts b/src/server/project.ts
index 1a27b63d2eaa2..a31574080b049 100644
--- a/src/server/project.ts
+++ b/src/server/project.ts
@@ -256,12 +256,12 @@ namespace ts.server {
 
         /*@internal*/
         public static async importServicePluginAsync(moduleName: string, initialDir: string, host: ServerHost, log: (message: string) => void, logErrors?: (message: string) => void): Promise<{} | undefined> {
-            Debug.assertIsDefined(host.importServicePlugin);
+            Debug.assertIsDefined(host.importPlugin);
             const resolvedPath = combinePaths(initialDir, "node_modules");
             log(`Dynamically importing ${moduleName} from ${initialDir} (resolved to ${resolvedPath})`);
             let result: ModuleImportResult;
             try {
-                result = await host.importServicePlugin(resolvedPath, moduleName);
+                result = await host.importPlugin(resolvedPath, moduleName);
             }
             catch (e) {
                 result = { module: undefined, error: e };
@@ -1607,7 +1607,7 @@ namespace ts.server {
         protected enableGlobalPlugins(options: CompilerOptions, pluginConfigOverrides: Map<any> | undefined): void {
             const host = this.projectService.host;
 
-            if (!host.require && !host.importServicePlugin) {
+            if (!host.require && !host.importPlugin) {
                 this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                 return;
             }
@@ -1658,7 +1658,7 @@ namespace ts.server {
          */
         /*@internal*/
         async beginEnablePluginAsync(pluginConfigEntry: PluginImport, searchPaths: string[], pluginConfigOverrides: Map<any> | undefined): Promise<BeginEnablePluginResult> {
-            Debug.assertIsDefined(this.projectService.host.importServicePlugin);
+            Debug.assertIsDefined(this.projectService.host.importPlugin);
 
             let errorLogs: string[] | undefined;
             const log = (message: string) => this.projectService.logger.info(message);
@@ -2522,8 +2522,7 @@ namespace ts.server {
         /*@internal*/
         enablePluginsWithOptions(options: CompilerOptions, pluginConfigOverrides: ESMap<string, any> | undefined): void {
             const host = this.projectService.host;
-
-            if (!host.require && !host.importServicePlugin) {
+            if (!host.require && !host.importPlugin) {
                 this.projectService.logger.info("Plugins were requested but not running in environment that supports 'require'. Nothing will be loaded");
                 return;
             }
diff --git a/src/server/types.ts b/src/server/types.ts
index b19879a94920f..2aa26f1231314 100644
--- a/src/server/types.ts
+++ b/src/server/types.ts
@@ -20,6 +20,7 @@ declare namespace ts.server {
         gc?(): void;
         trace?(s: string): void;
         require?(initialPath: string, moduleName: string): ModuleImportResult;
-        importServicePlugin?(root: string, moduleName: string): Promise<ModuleImportResult>;
+        /*@internal*/
+        importPlugin?(root: string, moduleName: string): Promise<ModuleImportResult>;
     }
 }
diff --git a/src/testRunner/unittests/tsbuild/containerOnlyReferenced.ts b/src/testRunner/unittests/tsbuild/containerOnlyReferenced.ts
index e9eacf1fa657c..595bc509744d5 100644
--- a/src/testRunner/unittests/tsbuild/containerOnlyReferenced.ts
+++ b/src/testRunner/unittests/tsbuild/containerOnlyReferenced.ts
@@ -7,5 +7,36 @@ namespace ts {
             commandLineArgs: ["--b", "/src", "--verbose"],
             edits: noChangeOnlyRuns
         });
+
+        verifyTscWithEdits({
+            scenario: "containerOnlyReferenced",
+            subScenario: "when solution is referenced indirectly",
+            fs: () => loadProjectFromFiles({
+                "/src/project1/tsconfig.json": JSON.stringify({
+                    compilerOptions: { composite: true },
+                    references: [],
+                }),
+                "/src/project2/tsconfig.json": JSON.stringify({
+                    compilerOptions: { composite: true },
+                    references: [],
+                }),
+                "/src/project2/src/b.ts": "export const b = 10;",
+                "/src/project3/tsconfig.json": JSON.stringify({
+                    compilerOptions: { composite: true },
+                    references: [{ path: "../project1", }, { path: "../project2" }],
+                }),
+                "/src/project3/src/c.ts": "export const c = 10;",
+                "/src/project4/tsconfig.json": JSON.stringify({
+                    compilerOptions: { composite: true },
+                    references: [{ path: "../project3" }]
+                }),
+                "/src/project4/src/d.ts": "export const d = 10;",
+            }),
+            commandLineArgs: ["--b", "/src/project4", "--verbose", "--explainFiles"],
+            edits: [{
+                subScenario: "modify project3 file",
+                modifyFs: fs => replaceText(fs, "/src/project3/src/c.ts", "c = ", "cc = "),
+            }],
+        });
     });
 }
diff --git a/src/testRunner/unittests/tscWatch/forceConsistentCasingInFileNames.ts b/src/testRunner/unittests/tscWatch/forceConsistentCasingInFileNames.ts
index 69ad855b626df..584b32c33535c 100644
--- a/src/testRunner/unittests/tscWatch/forceConsistentCasingInFileNames.ts
+++ b/src/testRunner/unittests/tscWatch/forceConsistentCasingInFileNames.ts
@@ -262,5 +262,69 @@ a;b;
         verifyDirSymlink("when import matches disk but directory symlink target does not", `${projectRoot}/XY`, `${projectRoot}/XY`, `./Xy`);
         verifyDirSymlink("when import and directory symlink target agree but do not match disk", `${projectRoot}/XY`, `${projectRoot}/Xy`, `./Xy`);
         verifyDirSymlink("when import, directory symlink target, and disk are all different", `${projectRoot}/XY`, `${projectRoot}/Xy`, `./yX`);
+
+        verifyTscWatch({
+            scenario: "forceConsistentCasingInFileNames",
+            subScenario: "with nodeNext resolution",
+            commandLineArgs: ["--w", "--explainFiles"],
+            sys: () => createWatchedSystem({
+                "/Users/name/projects/web/src/bin.ts": `import { foo } from "yargs";`,
+                "/Users/name/projects/web/node_modules/@types/yargs/index.d.ts": "export function foo(): void;",
+                "/Users/name/projects/web/node_modules/@types/yargs/index.d.mts": "export function foo(): void;",
+                "/Users/name/projects/web/node_modules/@types/yargs/package.json": JSON.stringify({
+                    name: "yargs",
+                    version: "17.0.12",
+                    exports: {
+                        ".": {
+                            types: {
+                                import: "./index.d.mts",
+                                default: "./index.d.ts"
+                            }
+                        },
+                    }
+                }),
+                "/Users/name/projects/web/tsconfig.json": JSON.stringify({
+                    compilerOptions: {
+                        moduleResolution: "nodenext",
+                        forceConsistentCasingInFileNames: true,
+                        traceResolution: true,
+                    }
+                }),
+                [libFile.path]: libFile.content,
+            }, { currentDirectory: "/Users/name/projects/web" }),
+            changes: emptyArray,
+        });
+
+        verifyTscWatch({
+            scenario: "forceConsistentCasingInFileNames",
+            subScenario: "self name package reference",
+            commandLineArgs: ["-w", "--explainFiles"],
+            sys: () => createWatchedSystem({
+                "/Users/name/projects/web/package.json": JSON.stringify({
+                    name: "@this/package",
+                    type: "module",
+                    exports: {
+                        ".": "./dist/index.js"
+                    }
+                }),
+                "/Users/name/projects/web/index.ts": Utils.dedent`
+                    import * as me from "@this/package";
+                    me.thing();
+                    export function thing(): void {}
+                `,
+                "/Users/name/projects/web/tsconfig.json": JSON.stringify({
+                    compilerOptions: {
+                        module: "nodenext",
+                        outDir: "./dist",
+                        declarationDir: "./types",
+                        composite: true,
+                        forceConsistentCasingInFileNames: true,
+                        traceResolution: true,
+                    }
+                }),
+                "/a/lib/lib.esnext.full.d.ts": libFile.content,
+            }, { currentDirectory: "/Users/name/projects/web" }),
+            changes: emptyArray,
+        });
     });
 }
diff --git a/src/testRunner/unittests/tsserver/webServer.ts b/src/testRunner/unittests/tsserver/webServer.ts
index d9f09eb4d4b2d..1e606ff01646d 100644
--- a/src/testRunner/unittests/tsserver/webServer.ts
+++ b/src/testRunner/unittests/tsserver/webServer.ts
@@ -29,7 +29,7 @@ namespace ts.projectSystem {
             }
         }
 
-        function setup(logLevel: server.LogLevel | undefined, options?: Partial<server.StartSessionOptions>, importServicePlugin?: server.ServerHost["importServicePlugin"]) {
+        function setup(logLevel: server.LogLevel | undefined, options?: Partial<server.StartSessionOptions>, importPlugin?: server.ServerHost["importPlugin"]) {
             const host = createServerHost([libFile], { windowsStyleRoot: "c:/" });
             const messages: any[] = [];
             const webHost: server.WebHost = {
@@ -38,7 +38,7 @@ namespace ts.projectSystem {
                 writeMessage: s => messages.push(s),
             };
             const webSys = server.createWebSystem(webHost, emptyArray, () => host.getExecutingFilePath());
-            webSys.importServicePlugin = importServicePlugin;
+            webSys.importPlugin = importPlugin;
             const logger = logLevel !== undefined ? new server.MainProcessLogger(logLevel, webHost) : nullLogger();
             const session = new TestWorkerSession(webSys, webHost, { serverMode: LanguageServiceMode.PartialSemantic, ...options }, logger);
             return { getMessages: () => messages, clearMessages: () => messages.length = 0, session };
@@ -161,7 +161,7 @@ namespace ts.projectSystem {
             it("plugins are not loaded immediately", async () => {
                 let pluginModuleInstantiated = false;
                 let pluginInvoked = false;
-                const importServicePlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
+                const importPlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
                     await Promise.resolve(); // simulate at least a single turn delay
                     pluginModuleInstantiated = true;
                     return {
@@ -173,7 +173,7 @@ namespace ts.projectSystem {
                     };
                 };
 
-                const { session } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importServicePlugin);
+                const { session } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importPlugin);
                 const projectService = session.getProjectService();
 
                 session.executeCommand({ seq: 1, type: "request", command: protocol.CommandTypes.Open, arguments: { file: "^memfs:/foo.ts", content: "" } });
@@ -201,7 +201,7 @@ namespace ts.projectSystem {
                 const pluginADeferred = Utils.defer();
                 const pluginBDeferred = Utils.defer();
                 const log: string[] = [];
-                const importServicePlugin = async (_root: string, moduleName: string): Promise<server.ModuleImportResult> => {
+                const importPlugin = async (_root: string, moduleName: string): Promise<server.ModuleImportResult> => {
                     log.push(`request import ${moduleName}`);
                     const promise = moduleName === "plugin-a" ? pluginADeferred.promise : pluginBDeferred.promise;
                     await promise;
@@ -215,7 +215,7 @@ namespace ts.projectSystem {
                     };
                 };
 
-                const { session } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a", "plugin-b"] }, importServicePlugin);
+                const { session } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a", "plugin-b"] }, importPlugin);
                 const projectService = session.getProjectService();
 
                 session.executeCommand({ seq: 1, type: "request", command: protocol.CommandTypes.Open, arguments: { file: "^memfs:/foo.ts", content: "" } });
@@ -241,7 +241,7 @@ namespace ts.projectSystem {
             });
 
             it("sends projectsUpdatedInBackground event", async () => {
-                const importServicePlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
+                const importPlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
                     await Promise.resolve(); // simulate at least a single turn delay
                     return {
                         module: (() => ({ create: info => info.languageService })) as server.PluginModuleFactory,
@@ -249,7 +249,7 @@ namespace ts.projectSystem {
                     };
                 };
 
-                const { session, getMessages } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importServicePlugin);
+                const { session, getMessages } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importPlugin);
                 const projectService = session.getProjectService();
 
                 session.executeCommand({ seq: 1, type: "request", command: protocol.CommandTypes.Open, arguments: { file: "^memfs:/foo.ts", content: "" } });
@@ -270,7 +270,7 @@ namespace ts.projectSystem {
                 const pluginAShouldLoad = Utils.defer();
                 const pluginAExternalFilesRequested = Utils.defer();
 
-                const importServicePlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
+                const importPlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
                     // wait until the initial external files are requested from the project service.
                     await pluginAShouldLoad.promise;
 
@@ -287,7 +287,7 @@ namespace ts.projectSystem {
                     };
                 };
 
-                const { session } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importServicePlugin);
+                const { session } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importPlugin);
                 const projectService = session.getProjectService();
 
                 session.executeCommand({ seq: 1, type: "request", command: protocol.CommandTypes.Open, arguments: { file: "^memfs:/foo.ts", content: "" } });
@@ -316,7 +316,7 @@ namespace ts.projectSystem {
             it("project is closed before plugins are loaded", async () => {
                 const pluginALoaded = Utils.defer();
                 const projectClosed = Utils.defer();
-                const importServicePlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
+                const importPlugin = async (_root: string, _moduleName: string): Promise<server.ModuleImportResult> => {
                     // mark that the plugin has started loading
                     pluginALoaded.resolve();
 
@@ -328,7 +328,7 @@ namespace ts.projectSystem {
                     };
                 };
 
-                const { session, getMessages } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importServicePlugin);
+                const { session, getMessages } = setup(/*logLevel*/ undefined, { globalPlugins: ["plugin-a"] }, importPlugin);
                 const projectService = session.getProjectService();
 
                 session.executeCommand({ seq: 1, type: "request", command: protocol.CommandTypes.Open, arguments: { file: "^memfs:/foo.ts", content: "" } });
diff --git a/src/webServer/webServer.ts b/src/webServer/webServer.ts
index 0cad87dd97b67..c989c00557ba4 100644
--- a/src/webServer/webServer.ts
+++ b/src/webServer/webServer.ts
@@ -162,7 +162,7 @@ namespace ts.server {
             clearImmediate: handle => clearTimeout(handle),
             /* eslint-enable no-restricted-globals */
 
-            importServicePlugin: async (initialDir: string, moduleName: string): Promise<ModuleImportResult> => {
+            importPlugin: async (initialDir: string, moduleName: string): Promise<ModuleImportResult> => {
                 const packageRoot = combinePaths(initialDir, moduleName);
 
                 let packageJson: any | undefined;
diff --git a/tests/baselines/reference/NonNullableInNonStrictMode.js b/tests/baselines/reference/NonNullableInNonStrictMode.js
new file mode 100644
index 0000000000000..e5a577ed7ba88
--- /dev/null
+++ b/tests/baselines/reference/NonNullableInNonStrictMode.js
@@ -0,0 +1,21 @@
+//// [NonNullableInNonStrictMode.ts]
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+type T1 = NonNullable<undefined>;
+type T2 = null & {};
+type T3 = undefined & {};
+type T4 = null & undefined;
+type T6 = null & { a: string } & {};
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+
+type IsNullWithoutStrictNullChecks = NonNullableNew<null>;
+type IsAlwaysNever = NonNullableOld<null>;
+
+
+//// [NonNullableInNonStrictMode.js]
+// These should all resolve to never
diff --git a/tests/baselines/reference/NonNullableInNonStrictMode.symbols b/tests/baselines/reference/NonNullableInNonStrictMode.symbols
new file mode 100644
index 0000000000000..b01bdc9cfbeee
--- /dev/null
+++ b/tests/baselines/reference/NonNullableInNonStrictMode.symbols
@@ -0,0 +1,45 @@
+=== tests/cases/compiler/NonNullableInNonStrictMode.ts ===
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+>T0 : Symbol(T0, Decl(NonNullableInNonStrictMode.ts, 0, 0))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+
+type T1 = NonNullable<undefined>;
+>T1 : Symbol(T1, Decl(NonNullableInNonStrictMode.ts, 2, 28))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+
+type T2 = null & {};
+>T2 : Symbol(T2, Decl(NonNullableInNonStrictMode.ts, 3, 33))
+
+type T3 = undefined & {};
+>T3 : Symbol(T3, Decl(NonNullableInNonStrictMode.ts, 4, 20))
+
+type T4 = null & undefined;
+>T4 : Symbol(T4, Decl(NonNullableInNonStrictMode.ts, 5, 25))
+
+type T6 = null & { a: string } & {};
+>T6 : Symbol(T6, Decl(NonNullableInNonStrictMode.ts, 6, 27))
+>a : Symbol(a, Decl(NonNullableInNonStrictMode.ts, 7, 18))
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+>NonNullableNew : Symbol(NonNullableNew, Decl(NonNullableInNonStrictMode.ts, 7, 36))
+>T : Symbol(T, Decl(NonNullableInNonStrictMode.ts, 11, 20))
+>T : Symbol(T, Decl(NonNullableInNonStrictMode.ts, 11, 20))
+
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+>NonNullableOld : Symbol(NonNullableOld, Decl(NonNullableInNonStrictMode.ts, 11, 32))
+>T : Symbol(T, Decl(NonNullableInNonStrictMode.ts, 12, 20))
+>T : Symbol(T, Decl(NonNullableInNonStrictMode.ts, 12, 20))
+>T : Symbol(T, Decl(NonNullableInNonStrictMode.ts, 12, 20))
+
+type IsNullWithoutStrictNullChecks = NonNullableNew<null>;
+>IsNullWithoutStrictNullChecks : Symbol(IsNullWithoutStrictNullChecks, Decl(NonNullableInNonStrictMode.ts, 12, 64))
+>NonNullableNew : Symbol(NonNullableNew, Decl(NonNullableInNonStrictMode.ts, 7, 36))
+
+type IsAlwaysNever = NonNullableOld<null>;
+>IsAlwaysNever : Symbol(IsAlwaysNever, Decl(NonNullableInNonStrictMode.ts, 14, 58))
+>NonNullableOld : Symbol(NonNullableOld, Decl(NonNullableInNonStrictMode.ts, 11, 32))
+
diff --git a/tests/baselines/reference/NonNullableInNonStrictMode.types b/tests/baselines/reference/NonNullableInNonStrictMode.types
new file mode 100644
index 0000000000000..cb2894ce0526b
--- /dev/null
+++ b/tests/baselines/reference/NonNullableInNonStrictMode.types
@@ -0,0 +1,43 @@
+=== tests/cases/compiler/NonNullableInNonStrictMode.ts ===
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+>T0 : never
+>null : null
+
+type T1 = NonNullable<undefined>;
+>T1 : never
+
+type T2 = null & {};
+>T2 : never
+>null : null
+
+type T3 = undefined & {};
+>T3 : never
+
+type T4 = null & undefined;
+>T4 : never
+>null : null
+
+type T6 = null & { a: string } & {};
+>T6 : never
+>null : null
+>a : string
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+>NonNullableNew : NonNullableNew<T>
+
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+>NonNullableOld : NonNullableOld<T>
+>null : null
+
+type IsNullWithoutStrictNullChecks = NonNullableNew<null>;
+>IsNullWithoutStrictNullChecks : never
+>null : null
+
+type IsAlwaysNever = NonNullableOld<null>;
+>IsAlwaysNever : never
+>null : null
+
diff --git a/tests/baselines/reference/allowSyntheticDefaultImports6.errors.txt b/tests/baselines/reference/allowSyntheticDefaultImports6.errors.txt
index 916f50162a121..fedd9b350ff9f 100644
--- a/tests/baselines/reference/allowSyntheticDefaultImports6.errors.txt
+++ b/tests/baselines/reference/allowSyntheticDefaultImports6.errors.txt
@@ -11,6 +11,6 @@ tests/cases/compiler/a.ts(1,8): error TS1259: Module '"tests/cases/compiler/b"'
     import Foo from "./b";
            ~~~
 !!! error TS1259: Module '"tests/cases/compiler/b"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/b.d.ts:4:1: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/b.d.ts:4:1: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     export var x = new Foo();
     
\ No newline at end of file
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index 4744d065a38ac..8003ac00a3c64 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -7033,7 +7033,6 @@ declare namespace ts.server {
         gc?(): void;
         trace?(s: string): void;
         require?(initialPath: string, moduleName: string): ModuleImportResult;
-        importServicePlugin?(root: string, moduleName: string): Promise<ModuleImportResult>;
     }
 }
 declare namespace ts.server {
diff --git a/tests/baselines/reference/conditionalTypes2.errors.txt b/tests/baselines/reference/conditionalTypes2.errors.txt
index a96ab6ac3a5d0..a96e6b907f749 100644
--- a/tests/baselines/reference/conditionalTypes2.errors.txt
+++ b/tests/baselines/reference/conditionalTypes2.errors.txt
@@ -32,7 +32,7 @@ tests/cases/conformance/types/conditional/conditionalTypes2.ts(74,12): error TS2
   Property 'bat' is missing in type 'Foo & Bar' but required in type '{ foo: string; bat: string; }'.
 tests/cases/conformance/types/conditional/conditionalTypes2.ts(75,12): error TS2345: Argument of type 'Extract2<T, Foo, Bar>' is not assignable to parameter of type '{ foo: string; bat: string; }'.
   Type 'T extends Bar ? T : never' is not assignable to type '{ foo: string; bat: string; }'.
-    Type 'Bar & Foo & T' is not assignable to type '{ foo: string; bat: string; }'.
+    Property 'bat' is missing in type 'Bar & Foo' but required in type '{ foo: string; bat: string; }'.
 
 
 ==== tests/cases/conformance/types/conditional/conditionalTypes2.ts (7 errors) ====
@@ -159,7 +159,8 @@ tests/cases/conformance/types/conditional/conditionalTypes2.ts(75,12): error TS2
                ~
 !!! error TS2345: Argument of type 'Extract2<T, Foo, Bar>' is not assignable to parameter of type '{ foo: string; bat: string; }'.
 !!! error TS2345:   Type 'T extends Bar ? T : never' is not assignable to type '{ foo: string; bat: string; }'.
-!!! error TS2345:     Type 'Bar & Foo & T' is not assignable to type '{ foo: string; bat: string; }'.
+!!! error TS2345:     Property 'bat' is missing in type 'Bar & Foo' but required in type '{ foo: string; bat: string; }'.
+!!! related TS2728 tests/cases/conformance/types/conditional/conditionalTypes2.ts:62:43: 'bat' is declared here.
     }
     
     // Repros from #22860
diff --git a/tests/baselines/reference/controlFlowGenericTypes.errors.txt b/tests/baselines/reference/controlFlowGenericTypes.errors.txt
index 3130ba416fb75..b2f1de6b88dd6 100644
--- a/tests/baselines/reference/controlFlowGenericTypes.errors.txt
+++ b/tests/baselines/reference/controlFlowGenericTypes.errors.txt
@@ -240,4 +240,12 @@ tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(168,9): error TS2
             control[key] = value;
         }
     }
+    
+    // Repro from #50465
+    
+    type Column<T> = (keyof T extends never ? { id?: number | string } : { id: T }) & { title?: string; }
+    
+    function getColumnProperty<T>(column: Column<T>, key: keyof Column<T>) {
+      return column[key];
+    }
     
\ No newline at end of file
diff --git a/tests/baselines/reference/controlFlowGenericTypes.js b/tests/baselines/reference/controlFlowGenericTypes.js
index a59b496ecd753..fbd4391269639 100644
--- a/tests/baselines/reference/controlFlowGenericTypes.js
+++ b/tests/baselines/reference/controlFlowGenericTypes.js
@@ -210,6 +210,14 @@ function update<T extends Control, K extends keyof T>(control : T | undefined, k
         control[key] = value;
     }
 }
+
+// Repro from #50465
+
+type Column<T> = (keyof T extends never ? { id?: number | string } : { id: T }) & { title?: string; }
+
+function getColumnProperty<T>(column: Column<T>, key: keyof Column<T>) {
+  return column[key];
+}
 
 
 //// [controlFlowGenericTypes.js]
@@ -368,3 +376,6 @@ function update(control, key, value) {
         control[key] = value;
     }
 }
+function getColumnProperty(column, key) {
+    return column[key];
+}
diff --git a/tests/baselines/reference/controlFlowGenericTypes.symbols b/tests/baselines/reference/controlFlowGenericTypes.symbols
index 1a1edf72f0afc..71b328efe87aa 100644
--- a/tests/baselines/reference/controlFlowGenericTypes.symbols
+++ b/tests/baselines/reference/controlFlowGenericTypes.symbols
@@ -626,3 +626,29 @@ function update<T extends Control, K extends keyof T>(control : T | undefined, k
     }
 }
 
+// Repro from #50465
+
+type Column<T> = (keyof T extends never ? { id?: number | string } : { id: T }) & { title?: string; }
+>Column : Symbol(Column, Decl(controlFlowGenericTypes.ts, 210, 1))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 214, 12))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 214, 12))
+>id : Symbol(id, Decl(controlFlowGenericTypes.ts, 214, 43))
+>id : Symbol(id, Decl(controlFlowGenericTypes.ts, 214, 70))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 214, 12))
+>title : Symbol(title, Decl(controlFlowGenericTypes.ts, 214, 83))
+
+function getColumnProperty<T>(column: Column<T>, key: keyof Column<T>) {
+>getColumnProperty : Symbol(getColumnProperty, Decl(controlFlowGenericTypes.ts, 214, 101))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 216, 27))
+>column : Symbol(column, Decl(controlFlowGenericTypes.ts, 216, 30))
+>Column : Symbol(Column, Decl(controlFlowGenericTypes.ts, 210, 1))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 216, 27))
+>key : Symbol(key, Decl(controlFlowGenericTypes.ts, 216, 48))
+>Column : Symbol(Column, Decl(controlFlowGenericTypes.ts, 210, 1))
+>T : Symbol(T, Decl(controlFlowGenericTypes.ts, 216, 27))
+
+  return column[key];
+>column : Symbol(column, Decl(controlFlowGenericTypes.ts, 216, 30))
+>key : Symbol(key, Decl(controlFlowGenericTypes.ts, 216, 48))
+}
+
diff --git a/tests/baselines/reference/controlFlowGenericTypes.types b/tests/baselines/reference/controlFlowGenericTypes.types
index e6ebd4226b700..c02307a26e2a7 100644
--- a/tests/baselines/reference/controlFlowGenericTypes.types
+++ b/tests/baselines/reference/controlFlowGenericTypes.types
@@ -583,3 +583,22 @@ function update<T extends Control, K extends keyof T>(control : T | undefined, k
     }
 }
 
+// Repro from #50465
+
+type Column<T> = (keyof T extends never ? { id?: number | string } : { id: T }) & { title?: string; }
+>Column : Column<T>
+>id : string | number | undefined
+>id : T
+>title : string | undefined
+
+function getColumnProperty<T>(column: Column<T>, key: keyof Column<T>) {
+>getColumnProperty : <T>(column: Column<T>, key: keyof Column<T>) => Column<T>["title" | keyof (keyof T extends never ? { id?: string | number | undefined; } : { id: T; })]
+>column : Column<T>
+>key : "title" | keyof (keyof T extends never ? { id?: string | number | undefined; } : { id: T; })
+
+  return column[key];
+>column[key] : Column<T>["title" | keyof (keyof T extends never ? { id?: string | number | undefined; } : { id: T; })]
+>column : Column<T>
+>key : "title" | keyof (keyof T extends never ? { id?: string | number | undefined; } : { id: T; })
+}
+
diff --git a/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).js b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).js
new file mode 100644
index 0000000000000..f543db3268926
--- /dev/null
+++ b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).js
@@ -0,0 +1,139 @@
+//// [emptyAnonymousObjectNarrowing.ts]
+declare let nonNull: {};
+if (nonNull === "foo") {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+declare let obj: { a: string };
+if (nonNull === obj) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+function f1<T>(x: T) {
+  if (nonNull === x) {
+    nonNull;
+  }
+  else {
+    nonNull;
+  }
+}
+
+function f2<T extends object>(x: T) {
+  if (nonNull === x) {
+    nonNull;
+  }
+  else {
+    nonNull;
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+if (nonNull === union) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull === undefined) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull === null) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull == undefined) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+  if (!value) {
+      return 'foo';
+  }
+  if (value === 'xyz') {
+      return value; // Type '{}' is not assignable to type 'string'.
+  }
+  return '';
+};
+
+
+//// [emptyAnonymousObjectNarrowing.js]
+if (nonNull === "foo") {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull === obj) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+function f1(x) {
+    if (nonNull === x) {
+        nonNull;
+    }
+    else {
+        nonNull;
+    }
+}
+function f2(x) {
+    if (nonNull === x) {
+        nonNull;
+    }
+    else {
+        nonNull;
+    }
+}
+if (nonNull === union) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull === undefined) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull === null) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull == undefined) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+// Repro from #50567
+var foo = function (value) {
+    if (!value) {
+        return 'foo';
+    }
+    if (value === 'xyz') {
+        return value; // Type '{}' is not assignable to type 'string'.
+    }
+    return '';
+};
diff --git a/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).symbols b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).symbols
new file mode 100644
index 0000000000000..1cf0efed0782d
--- /dev/null
+++ b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).symbols
@@ -0,0 +1,139 @@
+=== tests/cases/compiler/emptyAnonymousObjectNarrowing.ts ===
+declare let nonNull: {};
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+
+if (nonNull === "foo") {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+declare let obj: { a: string };
+>obj : Symbol(obj, Decl(emptyAnonymousObjectNarrowing.ts, 8, 11))
+>a : Symbol(a, Decl(emptyAnonymousObjectNarrowing.ts, 8, 18))
+
+if (nonNull === obj) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>obj : Symbol(obj, Decl(emptyAnonymousObjectNarrowing.ts, 8, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+function f1<T>(x: T) {
+>f1 : Symbol(f1, Decl(emptyAnonymousObjectNarrowing.ts, 14, 1))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 16, 12))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 16, 15))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 16, 12))
+
+  if (nonNull === x) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 16, 15))
+
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+  else {
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+}
+
+function f2<T extends object>(x: T) {
+>f2 : Symbol(f2, Decl(emptyAnonymousObjectNarrowing.ts, 23, 1))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 25, 12))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 25, 30))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 25, 12))
+
+  if (nonNull === x) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 25, 30))
+
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+  else {
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+>union : Symbol(union, Decl(emptyAnonymousObjectNarrowing.ts, 34, 11))
+>a : Symbol(a, Decl(emptyAnonymousObjectNarrowing.ts, 34, 28))
+
+if (nonNull === union) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>union : Symbol(union, Decl(emptyAnonymousObjectNarrowing.ts, 34, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+if (nonNull === undefined) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>undefined : Symbol(undefined)
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+if (nonNull === null) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+if (nonNull == undefined) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>undefined : Symbol(undefined)
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+>foo : Symbol(foo, Decl(emptyAnonymousObjectNarrowing.ts, 64, 5))
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+
+  if (!value) {
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+
+      return 'foo';
+  }
+  if (value === 'xyz') {
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+
+      return value; // Type '{}' is not assignable to type 'string'.
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+  }
+  return '';
+};
+
diff --git a/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).types b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).types
new file mode 100644
index 0000000000000..3ae0ad92788f1
--- /dev/null
+++ b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=false).types
@@ -0,0 +1,152 @@
+=== tests/cases/compiler/emptyAnonymousObjectNarrowing.ts ===
+declare let nonNull: {};
+>nonNull : {}
+
+if (nonNull === "foo") {
+>nonNull === "foo" : boolean
+>nonNull : {}
+>"foo" : "foo"
+
+  nonNull;
+>nonNull : "foo"
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+declare let obj: { a: string };
+>obj : { a: string; }
+>a : string
+
+if (nonNull === obj) {
+>nonNull === obj : boolean
+>nonNull : {}
+>obj : { a: string; }
+
+  nonNull;
+>nonNull : object
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+function f1<T>(x: T) {
+>f1 : <T>(x: T) => void
+>x : T
+
+  if (nonNull === x) {
+>nonNull === x : boolean
+>nonNull : {}
+>x : T
+
+    nonNull;
+>nonNull : {}
+  }
+  else {
+    nonNull;
+>nonNull : {}
+  }
+}
+
+function f2<T extends object>(x: T) {
+>f2 : <T extends object>(x: T) => void
+>x : T
+
+  if (nonNull === x) {
+>nonNull === x : boolean
+>nonNull : {}
+>x : T
+
+    nonNull;
+>nonNull : {}
+  }
+  else {
+    nonNull;
+>nonNull : {}
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+>union : { a: string; } | "xyz"
+>a : string
+
+if (nonNull === union) {
+>nonNull === union : boolean
+>nonNull : {}
+>union : { a: string; } | "xyz"
+
+  nonNull;
+>nonNull : {}
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+if (nonNull === undefined) {
+>nonNull === undefined : boolean
+>nonNull : {}
+>undefined : undefined
+
+  nonNull;
+>nonNull : {}
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+if (nonNull === null) {
+>nonNull === null : boolean
+>nonNull : {}
+>null : null
+
+  nonNull;
+>nonNull : {}
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+if (nonNull == undefined) {
+>nonNull == undefined : boolean
+>nonNull : {}
+>undefined : undefined
+
+  nonNull;
+>nonNull : {}
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+>foo : (value: unknown) => string
+>(value: unknown): string => {  if (!value) {      return 'foo';  }  if (value === 'xyz') {      return value; // Type '{}' is not assignable to type 'string'.  }  return '';} : (value: unknown) => string
+>value : unknown
+
+  if (!value) {
+>!value : boolean
+>value : unknown
+
+      return 'foo';
+>'foo' : "foo"
+  }
+  if (value === 'xyz') {
+>value === 'xyz' : boolean
+>value : unknown
+>'xyz' : "xyz"
+
+      return value; // Type '{}' is not assignable to type 'string'.
+>value : "xyz"
+  }
+  return '';
+>'' : ""
+
+};
+
diff --git a/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).js b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).js
new file mode 100644
index 0000000000000..f543db3268926
--- /dev/null
+++ b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).js
@@ -0,0 +1,139 @@
+//// [emptyAnonymousObjectNarrowing.ts]
+declare let nonNull: {};
+if (nonNull === "foo") {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+declare let obj: { a: string };
+if (nonNull === obj) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+function f1<T>(x: T) {
+  if (nonNull === x) {
+    nonNull;
+  }
+  else {
+    nonNull;
+  }
+}
+
+function f2<T extends object>(x: T) {
+  if (nonNull === x) {
+    nonNull;
+  }
+  else {
+    nonNull;
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+if (nonNull === union) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull === undefined) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull === null) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull == undefined) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+  if (!value) {
+      return 'foo';
+  }
+  if (value === 'xyz') {
+      return value; // Type '{}' is not assignable to type 'string'.
+  }
+  return '';
+};
+
+
+//// [emptyAnonymousObjectNarrowing.js]
+if (nonNull === "foo") {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull === obj) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+function f1(x) {
+    if (nonNull === x) {
+        nonNull;
+    }
+    else {
+        nonNull;
+    }
+}
+function f2(x) {
+    if (nonNull === x) {
+        nonNull;
+    }
+    else {
+        nonNull;
+    }
+}
+if (nonNull === union) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull === undefined) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull === null) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+if (nonNull == undefined) {
+    nonNull;
+}
+else {
+    nonNull;
+}
+// Repro from #50567
+var foo = function (value) {
+    if (!value) {
+        return 'foo';
+    }
+    if (value === 'xyz') {
+        return value; // Type '{}' is not assignable to type 'string'.
+    }
+    return '';
+};
diff --git a/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).symbols b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).symbols
new file mode 100644
index 0000000000000..1cf0efed0782d
--- /dev/null
+++ b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).symbols
@@ -0,0 +1,139 @@
+=== tests/cases/compiler/emptyAnonymousObjectNarrowing.ts ===
+declare let nonNull: {};
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+
+if (nonNull === "foo") {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+declare let obj: { a: string };
+>obj : Symbol(obj, Decl(emptyAnonymousObjectNarrowing.ts, 8, 11))
+>a : Symbol(a, Decl(emptyAnonymousObjectNarrowing.ts, 8, 18))
+
+if (nonNull === obj) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>obj : Symbol(obj, Decl(emptyAnonymousObjectNarrowing.ts, 8, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+function f1<T>(x: T) {
+>f1 : Symbol(f1, Decl(emptyAnonymousObjectNarrowing.ts, 14, 1))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 16, 12))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 16, 15))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 16, 12))
+
+  if (nonNull === x) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 16, 15))
+
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+  else {
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+}
+
+function f2<T extends object>(x: T) {
+>f2 : Symbol(f2, Decl(emptyAnonymousObjectNarrowing.ts, 23, 1))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 25, 12))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 25, 30))
+>T : Symbol(T, Decl(emptyAnonymousObjectNarrowing.ts, 25, 12))
+
+  if (nonNull === x) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>x : Symbol(x, Decl(emptyAnonymousObjectNarrowing.ts, 25, 30))
+
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+  else {
+    nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+>union : Symbol(union, Decl(emptyAnonymousObjectNarrowing.ts, 34, 11))
+>a : Symbol(a, Decl(emptyAnonymousObjectNarrowing.ts, 34, 28))
+
+if (nonNull === union) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>union : Symbol(union, Decl(emptyAnonymousObjectNarrowing.ts, 34, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+if (nonNull === undefined) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>undefined : Symbol(undefined)
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+if (nonNull === null) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+if (nonNull == undefined) {
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+>undefined : Symbol(undefined)
+
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+else {
+  nonNull;
+>nonNull : Symbol(nonNull, Decl(emptyAnonymousObjectNarrowing.ts, 0, 11))
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+>foo : Symbol(foo, Decl(emptyAnonymousObjectNarrowing.ts, 64, 5))
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+
+  if (!value) {
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+
+      return 'foo';
+  }
+  if (value === 'xyz') {
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+
+      return value; // Type '{}' is not assignable to type 'string'.
+>value : Symbol(value, Decl(emptyAnonymousObjectNarrowing.ts, 64, 13))
+  }
+  return '';
+};
+
diff --git a/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).types b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).types
new file mode 100644
index 0000000000000..621db01774a99
--- /dev/null
+++ b/tests/baselines/reference/emptyAnonymousObjectNarrowing(strictnullchecks=true).types
@@ -0,0 +1,152 @@
+=== tests/cases/compiler/emptyAnonymousObjectNarrowing.ts ===
+declare let nonNull: {};
+>nonNull : {}
+
+if (nonNull === "foo") {
+>nonNull === "foo" : boolean
+>nonNull : {}
+>"foo" : "foo"
+
+  nonNull;
+>nonNull : "foo"
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+declare let obj: { a: string };
+>obj : { a: string; }
+>a : string
+
+if (nonNull === obj) {
+>nonNull === obj : boolean
+>nonNull : {}
+>obj : { a: string; }
+
+  nonNull;
+>nonNull : object
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+function f1<T>(x: T) {
+>f1 : <T>(x: T) => void
+>x : T
+
+  if (nonNull === x) {
+>nonNull === x : boolean
+>nonNull : {}
+>x : T
+
+    nonNull;
+>nonNull : {}
+  }
+  else {
+    nonNull;
+>nonNull : {}
+  }
+}
+
+function f2<T extends object>(x: T) {
+>f2 : <T extends object>(x: T) => void
+>x : T
+
+  if (nonNull === x) {
+>nonNull === x : boolean
+>nonNull : {}
+>x : T
+
+    nonNull;
+>nonNull : {}
+  }
+  else {
+    nonNull;
+>nonNull : {}
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+>union : { a: string; } | "xyz" | undefined
+>a : string
+
+if (nonNull === union) {
+>nonNull === union : boolean
+>nonNull : {}
+>union : { a: string; } | "xyz" | undefined
+
+  nonNull;
+>nonNull : {}
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+if (nonNull === undefined) {
+>nonNull === undefined : boolean
+>nonNull : {}
+>undefined : undefined
+
+  nonNull;
+>nonNull : never
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+if (nonNull === null) {
+>nonNull === null : boolean
+>nonNull : {}
+>null : null
+
+  nonNull;
+>nonNull : never
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+if (nonNull == undefined) {
+>nonNull == undefined : boolean
+>nonNull : {}
+>undefined : undefined
+
+  nonNull;
+>nonNull : never
+}
+else {
+  nonNull;
+>nonNull : {}
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+>foo : (value: unknown) => string
+>(value: unknown): string => {  if (!value) {      return 'foo';  }  if (value === 'xyz') {      return value; // Type '{}' is not assignable to type 'string'.  }  return '';} : (value: unknown) => string
+>value : unknown
+
+  if (!value) {
+>!value : boolean
+>value : unknown
+
+      return 'foo';
+>'foo' : "foo"
+  }
+  if (value === 'xyz') {
+>value === 'xyz' : boolean
+>value : {}
+>'xyz' : "xyz"
+
+      return value; // Type '{}' is not assignable to type 'string'.
+>value : "xyz"
+  }
+  return '';
+>'' : ""
+
+};
+
diff --git a/tests/baselines/reference/es6ExportEqualsInterop.errors.txt b/tests/baselines/reference/es6ExportEqualsInterop.errors.txt
index d7b992f2c1607..b1e3ac15f6b3b 100644
--- a/tests/baselines/reference/es6ExportEqualsInterop.errors.txt
+++ b/tests/baselines/reference/es6ExportEqualsInterop.errors.txt
@@ -77,43 +77,43 @@ tests/cases/compiler/main.ts(106,15): error TS2498: Module '"class-module"' uses
     import x1 from "interface";
            ~~
 !!! error TS1259: Module '"interface"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:6:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:6:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x2 from "variable";
            ~~
 !!! error TS1259: Module '"variable"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:14:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:14:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x3 from "interface-variable";
            ~~
 !!! error TS1259: Module '"interface-variable"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:26:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:26:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x4 from "module";
            ~~
 !!! error TS1259: Module '"module"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:34:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:34:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x5 from "interface-module";
            ~~
 !!! error TS1259: Module '"interface-module"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:46:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:46:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x6 from "variable-module";
            ~~
 !!! error TS1259: Module '"variable-module"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:60:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:60:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x7 from "function";
            ~~
 !!! error TS1259: Module '"function"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:65:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:65:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x8 from "function-module";
            ~~
 !!! error TS1259: Module '"function-module"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:74:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:74:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x9 from "class";
            ~~
 !!! error TS1259: Module '"class"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:82:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:82:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     import x0 from "class-module";
            ~~
 !!! error TS1259: Module '"class-module"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/modules.d.ts:94:5: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 tests/cases/compiler/modules.d.ts:94:5: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     
     // namespace import
     import * as y1 from "interface";
diff --git a/tests/baselines/reference/es6ImportDefaultBindingInEs5.errors.txt b/tests/baselines/reference/es6ImportDefaultBindingInEs5.errors.txt
index 924792bf98adf..3eb6dd0e8b6c2 100644
--- a/tests/baselines/reference/es6ImportDefaultBindingInEs5.errors.txt
+++ b/tests/baselines/reference/es6ImportDefaultBindingInEs5.errors.txt
@@ -9,4 +9,4 @@ tests/cases/compiler/es6ImportDefaultBindingInEs5_1.ts(1,8): error TS1259: Modul
     import defaultBinding from "./es6ImportDefaultBindingInEs5_0";
            ~~~~~~~~~~~~~~
 !!! error TS1259: Module '"tests/cases/compiler/es6ImportDefaultBindingInEs5_0"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 tests/cases/compiler/es6ImportDefaultBindingInEs5_0.ts:2:1: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
\ No newline at end of file
+!!! related TS2594 tests/cases/compiler/es6ImportDefaultBindingInEs5_0.ts:2:1: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
\ No newline at end of file
diff --git a/tests/baselines/reference/esModuleInteropDefaultImports.errors.txt b/tests/baselines/reference/esModuleInteropDefaultImports.errors.txt
new file mode 100644
index 0000000000000..f91da0382ed37
--- /dev/null
+++ b/tests/baselines/reference/esModuleInteropDefaultImports.errors.txt
@@ -0,0 +1,67 @@
+tests/cases/compiler/b.ts(15,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.ts(16,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.ts(17,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.ts(18,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.ts(19,6): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.ts(20,6): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+
+
+==== tests/cases/compiler/mod.ts (0 errors) ====
+    declare function fun(): void;
+    export default fun;
+==== tests/cases/compiler/a.ts (0 errors) ====
+    import mod = require("./mod");
+    export = mod;
+==== tests/cases/compiler/b.ts (6 errors) ====
+    import a from "./a";
+    import { default as b } from "./a";
+    import c, { default as d } from "./a";
+    import * as self from "./b";
+    export { default } from "./a";
+    export { default as def } from "./a";
+    
+    a === b;
+    b === c;
+    c === d;
+    d === self.default;
+    self.default === self.def;
+    
+    // should all fail
+    a();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    b();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    c();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    d();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    self.default();
+         ~~~~~~~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    self.def();
+         ~~~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    
+    // should all work
+    a.default();
+    b.default();
+    c.default();
+    d.default();
+    self.default.default();
+    self.def.default();
\ No newline at end of file
diff --git a/tests/baselines/reference/esModuleInteropDefaultImports.js b/tests/baselines/reference/esModuleInteropDefaultImports.js
new file mode 100644
index 0000000000000..f893e0e968b99
--- /dev/null
+++ b/tests/baselines/reference/esModuleInteropDefaultImports.js
@@ -0,0 +1,103 @@
+//// [tests/cases/compiler/esModuleInteropDefaultImports.ts] ////
+
+//// [mod.ts]
+declare function fun(): void;
+export default fun;
+//// [a.ts]
+import mod = require("./mod");
+export = mod;
+//// [b.ts]
+import a from "./a";
+import { default as b } from "./a";
+import c, { default as d } from "./a";
+import * as self from "./b";
+export { default } from "./a";
+export { default as def } from "./a";
+
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
+
+//// [mod.js]
+"use strict";
+exports.__esModule = true;
+exports["default"] = fun;
+//// [a.js]
+"use strict";
+var mod = require("./mod");
+module.exports = mod;
+//// [b.js]
+"use strict";
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
+    Object.defineProperty(o, "default", { enumerable: true, value: v });
+}) : function(o, v) {
+    o["default"] = v;
+});
+var __importStar = (this && this.__importStar) || function (mod) {
+    if (mod && mod.__esModule) return mod;
+    var result = {};
+    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    __setModuleDefault(result, mod);
+    return result;
+};
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
+exports.__esModule = true;
+exports.def = exports["default"] = void 0;
+var a_1 = __importDefault(require("./a"));
+var a_2 = __importDefault(require("./a"));
+var a_3 = __importDefault(require("./a"));
+var self = __importStar(require("./b"));
+var a_4 = require("./a");
+__createBinding(exports, a_4, "default");
+var a_5 = require("./a");
+__createBinding(exports, a_5, "default", "def");
+a_1["default"] === a_2["default"];
+a_2["default"] === a_3["default"];
+a_3["default"] === a_3["default"];
+a_3["default"] === self["default"];
+self["default"] === self.def;
+// should all fail
+(0, a_1["default"])();
+(0, a_2["default"])();
+(0, a_3["default"])();
+(0, a_3["default"])();
+self["default"]();
+self.def();
+// should all work
+a_1["default"]["default"]();
+a_2["default"]["default"]();
+a_3["default"]["default"]();
+a_3["default"]["default"]();
+self["default"]["default"]();
+self.def["default"]();
diff --git a/tests/baselines/reference/esModuleInteropDefaultImports.symbols b/tests/baselines/reference/esModuleInteropDefaultImports.symbols
new file mode 100644
index 0000000000000..05c18c13e4cfb
--- /dev/null
+++ b/tests/baselines/reference/esModuleInteropDefaultImports.symbols
@@ -0,0 +1,121 @@
+=== tests/cases/compiler/mod.ts ===
+declare function fun(): void;
+>fun : Symbol(fun, Decl(mod.ts, 0, 0))
+
+export default fun;
+>fun : Symbol(fun, Decl(mod.ts, 0, 0))
+
+=== tests/cases/compiler/a.ts ===
+import mod = require("./mod");
+>mod : Symbol(mod, Decl(a.ts, 0, 0))
+
+export = mod;
+>mod : Symbol(mod, Decl(a.ts, 0, 0))
+
+=== tests/cases/compiler/b.ts ===
+import a from "./a";
+>a : Symbol(a, Decl(b.ts, 0, 6))
+
+import { default as b } from "./a";
+>default : Symbol(mod, Decl(a.ts, 0, 30))
+>b : Symbol(b, Decl(b.ts, 1, 8))
+
+import c, { default as d } from "./a";
+>c : Symbol(c, Decl(b.ts, 2, 6))
+>default : Symbol(mod, Decl(a.ts, 0, 30))
+>d : Symbol(d, Decl(b.ts, 2, 11))
+
+import * as self from "./b";
+>self : Symbol(self, Decl(b.ts, 3, 6))
+
+export { default } from "./a";
+>default : Symbol(self.default, Decl(b.ts, 4, 8))
+
+export { default as def } from "./a";
+>default : Symbol(mod, Decl(a.ts, 0, 30))
+>def : Symbol(self.def, Decl(b.ts, 5, 8))
+
+a === b;
+>a : Symbol(a, Decl(b.ts, 0, 6))
+>b : Symbol(b, Decl(b.ts, 1, 8))
+
+b === c;
+>b : Symbol(b, Decl(b.ts, 1, 8))
+>c : Symbol(c, Decl(b.ts, 2, 6))
+
+c === d;
+>c : Symbol(c, Decl(b.ts, 2, 6))
+>d : Symbol(d, Decl(b.ts, 2, 11))
+
+d === self.default;
+>d : Symbol(d, Decl(b.ts, 2, 11))
+>self.default : Symbol(self.default, Decl(b.ts, 4, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>default : Symbol(self.default, Decl(b.ts, 4, 8))
+
+self.default === self.def;
+>self.default : Symbol(self.default, Decl(b.ts, 4, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>default : Symbol(self.default, Decl(b.ts, 4, 8))
+>self.def : Symbol(self.def, Decl(b.ts, 5, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>def : Symbol(self.def, Decl(b.ts, 5, 8))
+
+// should all fail
+a();
+>a : Symbol(a, Decl(b.ts, 0, 6))
+
+b();
+>b : Symbol(b, Decl(b.ts, 1, 8))
+
+c();
+>c : Symbol(c, Decl(b.ts, 2, 6))
+
+d();
+>d : Symbol(d, Decl(b.ts, 2, 11))
+
+self.default();
+>self.default : Symbol(self.default, Decl(b.ts, 4, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>default : Symbol(self.default, Decl(b.ts, 4, 8))
+
+self.def();
+>self.def : Symbol(self.def, Decl(b.ts, 5, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>def : Symbol(self.def, Decl(b.ts, 5, 8))
+
+// should all work
+a.default();
+>a.default : Symbol(a.default, Decl(mod.ts, 0, 29))
+>a : Symbol(a, Decl(b.ts, 0, 6))
+>default : Symbol(a.default, Decl(mod.ts, 0, 29))
+
+b.default();
+>b.default : Symbol(a.default, Decl(mod.ts, 0, 29))
+>b : Symbol(b, Decl(b.ts, 1, 8))
+>default : Symbol(a.default, Decl(mod.ts, 0, 29))
+
+c.default();
+>c.default : Symbol(a.default, Decl(mod.ts, 0, 29))
+>c : Symbol(c, Decl(b.ts, 2, 6))
+>default : Symbol(a.default, Decl(mod.ts, 0, 29))
+
+d.default();
+>d.default : Symbol(a.default, Decl(mod.ts, 0, 29))
+>d : Symbol(d, Decl(b.ts, 2, 11))
+>default : Symbol(a.default, Decl(mod.ts, 0, 29))
+
+self.default.default();
+>self.default.default : Symbol(a.default, Decl(mod.ts, 0, 29))
+>self.default : Symbol(self.default, Decl(b.ts, 4, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>default : Symbol(self.default, Decl(b.ts, 4, 8))
+>default : Symbol(a.default, Decl(mod.ts, 0, 29))
+
+self.def.default();
+>self.def.default : Symbol(a.default, Decl(mod.ts, 0, 29))
+>self.def : Symbol(self.def, Decl(b.ts, 5, 8))
+>self : Symbol(self, Decl(b.ts, 3, 6))
+>def : Symbol(self.def, Decl(b.ts, 5, 8))
+>default : Symbol(a.default, Decl(mod.ts, 0, 29))
+
diff --git a/tests/baselines/reference/esModuleInteropDefaultImports.types b/tests/baselines/reference/esModuleInteropDefaultImports.types
new file mode 100644
index 0000000000000..961e7063b2f9e
--- /dev/null
+++ b/tests/baselines/reference/esModuleInteropDefaultImports.types
@@ -0,0 +1,138 @@
+=== tests/cases/compiler/mod.ts ===
+declare function fun(): void;
+>fun : () => void
+
+export default fun;
+>fun : () => void
+
+=== tests/cases/compiler/a.ts ===
+import mod = require("./mod");
+>mod : typeof mod
+
+export = mod;
+>mod : typeof mod
+
+=== tests/cases/compiler/b.ts ===
+import a from "./a";
+>a : typeof a
+
+import { default as b } from "./a";
+>default : typeof a
+>b : typeof a
+
+import c, { default as d } from "./a";
+>c : typeof a
+>default : typeof a
+>d : typeof a
+
+import * as self from "./b";
+>self : typeof self
+
+export { default } from "./a";
+>default : typeof a
+
+export { default as def } from "./a";
+>default : typeof a
+>def : typeof a
+
+a === b;
+>a === b : boolean
+>a : typeof a
+>b : typeof a
+
+b === c;
+>b === c : boolean
+>b : typeof a
+>c : typeof a
+
+c === d;
+>c === d : boolean
+>c : typeof a
+>d : typeof a
+
+d === self.default;
+>d === self.default : boolean
+>d : typeof a
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+
+self.default === self.def;
+>self.default === self.def : boolean
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+
+// should all fail
+a();
+>a() : any
+>a : typeof a
+
+b();
+>b() : any
+>b : typeof a
+
+c();
+>c() : any
+>c : typeof a
+
+d();
+>d() : any
+>d : typeof a
+
+self.default();
+>self.default() : any
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+
+self.def();
+>self.def() : any
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+
+// should all work
+a.default();
+>a.default() : void
+>a.default : () => void
+>a : typeof a
+>default : () => void
+
+b.default();
+>b.default() : void
+>b.default : () => void
+>b : typeof a
+>default : () => void
+
+c.default();
+>c.default() : void
+>c.default : () => void
+>c : typeof a
+>default : () => void
+
+d.default();
+>d.default() : void
+>d.default : () => void
+>d : typeof a
+>default : () => void
+
+self.default.default();
+>self.default.default() : void
+>self.default.default : () => void
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+>default : () => void
+
+self.def.default();
+>self.def.default() : void
+>self.def.default : () => void
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+>default : () => void
+
diff --git a/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.js b/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.js
new file mode 100644
index 0000000000000..971053105ca0a
--- /dev/null
+++ b/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.js
@@ -0,0 +1,10 @@
+//// [excessPropertyCheckingIntersectionWithConditional.ts]
+type Foo<K> = K extends unknown ? { a: number } : unknown
+const createDefaultExample = <K,>(x: K): Foo<K> & { x: K; } => {
+  return { a: 1, x: x }; // okay in TS 4.7.4, error in TS 4.8.2
+}
+
+//// [excessPropertyCheckingIntersectionWithConditional.js]
+var createDefaultExample = function (x) {
+    return { a: 1, x: x }; // okay in TS 4.7.4, error in TS 4.8.2
+};
diff --git a/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.symbols b/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.symbols
new file mode 100644
index 0000000000000..aca3252c77402
--- /dev/null
+++ b/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.symbols
@@ -0,0 +1,22 @@
+=== tests/cases/compiler/excessPropertyCheckingIntersectionWithConditional.ts ===
+type Foo<K> = K extends unknown ? { a: number } : unknown
+>Foo : Symbol(Foo, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 0, 0))
+>K : Symbol(K, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 0, 9))
+>K : Symbol(K, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 0, 9))
+>a : Symbol(a, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 0, 35))
+
+const createDefaultExample = <K,>(x: K): Foo<K> & { x: K; } => {
+>createDefaultExample : Symbol(createDefaultExample, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 5))
+>K : Symbol(K, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 30))
+>x : Symbol(x, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 34))
+>K : Symbol(K, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 30))
+>Foo : Symbol(Foo, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 0, 0))
+>K : Symbol(K, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 30))
+>x : Symbol(x, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 51))
+>K : Symbol(K, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 30))
+
+  return { a: 1, x: x }; // okay in TS 4.7.4, error in TS 4.8.2
+>a : Symbol(a, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 2, 10))
+>x : Symbol(x, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 2, 16))
+>x : Symbol(x, Decl(excessPropertyCheckingIntersectionWithConditional.ts, 1, 34))
+}
diff --git a/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.types b/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.types
new file mode 100644
index 0000000000000..5d2ec637e8da2
--- /dev/null
+++ b/tests/baselines/reference/excessPropertyCheckingIntersectionWithConditional.types
@@ -0,0 +1,18 @@
+=== tests/cases/compiler/excessPropertyCheckingIntersectionWithConditional.ts ===
+type Foo<K> = K extends unknown ? { a: number } : unknown
+>Foo : Foo<K>
+>a : number
+
+const createDefaultExample = <K,>(x: K): Foo<K> & { x: K; } => {
+>createDefaultExample : <K>(x: K) => Foo<K> & { x: K; }
+><K,>(x: K): Foo<K> & { x: K; } => {  return { a: 1, x: x }; // okay in TS 4.7.4, error in TS 4.8.2} : <K>(x: K) => Foo<K> & { x: K; }
+>x : K
+>x : K
+
+  return { a: 1, x: x }; // okay in TS 4.7.4, error in TS 4.8.2
+>{ a: 1, x: x } : { a: number; x: K; }
+>a : number
+>1 : 1
+>x : K
+>x : K
+}
diff --git a/tests/baselines/reference/exportAssignmentWithoutAllowSyntheticDefaultImportsError.errors.txt b/tests/baselines/reference/exportAssignmentWithoutAllowSyntheticDefaultImportsError.errors.txt
index d59ec8b42c86f..ba44def77ef37 100644
--- a/tests/baselines/reference/exportAssignmentWithoutAllowSyntheticDefaultImportsError.errors.txt
+++ b/tests/baselines/reference/exportAssignmentWithoutAllowSyntheticDefaultImportsError.errors.txt
@@ -12,4 +12,4 @@
     import bar from './bar';
            ~~~
 !!! error TS1259: Module '"/bar"' can only be default-imported using the 'allowSyntheticDefaultImports' flag
-!!! related TS2594 /bar.ts:1:1: This module is declared with using 'export =', and can only be used with a default import when using the 'allowSyntheticDefaultImports' flag.
\ No newline at end of file
+!!! related TS2594 /bar.ts:1:1: This module is declared with 'export =', and can only be used with a default import when using the 'allowSyntheticDefaultImports' flag.
\ No newline at end of file
diff --git a/tests/baselines/reference/inKeywordAndUnknown.js b/tests/baselines/reference/inKeywordAndUnknown.js
new file mode 100644
index 0000000000000..354bb8c4b1884
--- /dev/null
+++ b/tests/baselines/reference/inKeywordAndUnknown.js
@@ -0,0 +1,36 @@
+//// [inKeywordAndUnknown.ts]
+// Repro from #50531
+
+function f(x: {}, y: unknown) {
+    if (!("a" in x)) {
+        return;
+    }
+    x;  // {}
+    if (!y) {
+        return;
+    }
+    y;  // {}
+    if (!("a" in y)) {
+        return;
+    }
+    y;  // {}
+}
+
+
+//// [inKeywordAndUnknown.js]
+"use strict";
+// Repro from #50531
+function f(x, y) {
+    if (!("a" in x)) {
+        return;
+    }
+    x; // {}
+    if (!y) {
+        return;
+    }
+    y; // {}
+    if (!("a" in y)) {
+        return;
+    }
+    y; // {}
+}
diff --git a/tests/baselines/reference/inKeywordAndUnknown.symbols b/tests/baselines/reference/inKeywordAndUnknown.symbols
new file mode 100644
index 0000000000000..145e92dc7f657
--- /dev/null
+++ b/tests/baselines/reference/inKeywordAndUnknown.symbols
@@ -0,0 +1,33 @@
+=== tests/cases/compiler/inKeywordAndUnknown.ts ===
+// Repro from #50531
+
+function f(x: {}, y: unknown) {
+>f : Symbol(f, Decl(inKeywordAndUnknown.ts, 0, 0))
+>x : Symbol(x, Decl(inKeywordAndUnknown.ts, 2, 11))
+>y : Symbol(y, Decl(inKeywordAndUnknown.ts, 2, 17))
+
+    if (!("a" in x)) {
+>x : Symbol(x, Decl(inKeywordAndUnknown.ts, 2, 11))
+
+        return;
+    }
+    x;  // {}
+>x : Symbol(x, Decl(inKeywordAndUnknown.ts, 2, 11))
+
+    if (!y) {
+>y : Symbol(y, Decl(inKeywordAndUnknown.ts, 2, 17))
+
+        return;
+    }
+    y;  // {}
+>y : Symbol(y, Decl(inKeywordAndUnknown.ts, 2, 17))
+
+    if (!("a" in y)) {
+>y : Symbol(y, Decl(inKeywordAndUnknown.ts, 2, 17))
+
+        return;
+    }
+    y;  // {}
+>y : Symbol(y, Decl(inKeywordAndUnknown.ts, 2, 17))
+}
+
diff --git a/tests/baselines/reference/inKeywordAndUnknown.types b/tests/baselines/reference/inKeywordAndUnknown.types
new file mode 100644
index 0000000000000..74345ca004547
--- /dev/null
+++ b/tests/baselines/reference/inKeywordAndUnknown.types
@@ -0,0 +1,42 @@
+=== tests/cases/compiler/inKeywordAndUnknown.ts ===
+// Repro from #50531
+
+function f(x: {}, y: unknown) {
+>f : (x: {}, y: unknown) => void
+>x : {}
+>y : unknown
+
+    if (!("a" in x)) {
+>!("a" in x) : boolean
+>("a" in x) : boolean
+>"a" in x : boolean
+>"a" : "a"
+>x : {}
+
+        return;
+    }
+    x;  // {}
+>x : {}
+
+    if (!y) {
+>!y : boolean
+>y : unknown
+
+        return;
+    }
+    y;  // {}
+>y : {}
+
+    if (!("a" in y)) {
+>!("a" in y) : boolean
+>("a" in y) : boolean
+>"a" in y : boolean
+>"a" : "a"
+>y : {}
+
+        return;
+    }
+    y;  // {}
+>y : {}
+}
+
diff --git a/tests/baselines/reference/javascriptImportDefaultBadExport.errors.txt b/tests/baselines/reference/javascriptImportDefaultBadExport.errors.txt
index 71ff85e2155fe..e5631c22a89ed 100644
--- a/tests/baselines/reference/javascriptImportDefaultBadExport.errors.txt
+++ b/tests/baselines/reference/javascriptImportDefaultBadExport.errors.txt
@@ -12,5 +12,5 @@
     import a from "./a";
            ~
 !!! error TS1259: Module '"/a"' can only be default-imported using the 'esModuleInterop' flag
-!!! related TS2594 /a.js:5:1: This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+!!! related TS2594 /a.js:5:1: This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
     
\ No newline at end of file
diff --git a/tests/baselines/reference/jsxIntrinsicElementsCompatability.js b/tests/baselines/reference/jsxIntrinsicElementsCompatability.js
new file mode 100644
index 0000000000000..4381071491dba
--- /dev/null
+++ b/tests/baselines/reference/jsxIntrinsicElementsCompatability.js
@@ -0,0 +1,24 @@
+//// [jsxIntrinsicElementsCompatability.tsx]
+/// <reference path="/.lib/react16.d.ts" />
+import * as React from "react";
+function SomeComponent<T extends 'button' | 'a'>(props: { element?: T } & JSX.IntrinsicElements[T]): JSX.Element {
+    // Just so the return value is RectElement, the rendered element doesnt matter
+    return <div />
+}
+
+function Test<T extends 'button' | 'a'>(el: T) {
+    return <SomeComponent element={el} />
+}
+
+//// [jsxIntrinsicElementsCompatability.js]
+"use strict";
+exports.__esModule = true;
+/// <reference path="react16.d.ts" />
+var React = require("react");
+function SomeComponent(props) {
+    // Just so the return value is RectElement, the rendered element doesnt matter
+    return React.createElement("div", null);
+}
+function Test(el) {
+    return React.createElement(SomeComponent, { element: el });
+}
diff --git a/tests/baselines/reference/jsxIntrinsicElementsCompatability.symbols b/tests/baselines/reference/jsxIntrinsicElementsCompatability.symbols
new file mode 100644
index 0000000000000..86da5d624acd1
--- /dev/null
+++ b/tests/baselines/reference/jsxIntrinsicElementsCompatability.symbols
@@ -0,0 +1,33 @@
+=== tests/cases/compiler/jsxIntrinsicElementsCompatability.tsx ===
+/// <reference path="react16.d.ts" />
+import * as React from "react";
+>React : Symbol(React, Decl(jsxIntrinsicElementsCompatability.tsx, 1, 6))
+
+function SomeComponent<T extends 'button' | 'a'>(props: { element?: T } & JSX.IntrinsicElements[T]): JSX.Element {
+>SomeComponent : Symbol(SomeComponent, Decl(jsxIntrinsicElementsCompatability.tsx, 1, 31))
+>T : Symbol(T, Decl(jsxIntrinsicElementsCompatability.tsx, 2, 23))
+>props : Symbol(props, Decl(jsxIntrinsicElementsCompatability.tsx, 2, 49))
+>element : Symbol(element, Decl(jsxIntrinsicElementsCompatability.tsx, 2, 57))
+>T : Symbol(T, Decl(jsxIntrinsicElementsCompatability.tsx, 2, 23))
+>JSX : Symbol(JSX, Decl(react16.d.ts, 2493, 12))
+>IntrinsicElements : Symbol(JSX.IntrinsicElements, Decl(react16.d.ts, 2514, 86))
+>T : Symbol(T, Decl(jsxIntrinsicElementsCompatability.tsx, 2, 23))
+>JSX : Symbol(JSX, Decl(react16.d.ts, 2493, 12))
+>Element : Symbol(JSX.Element, Decl(react16.d.ts, 2494, 23))
+
+    // Just so the return value is RectElement, the rendered element doesnt matter
+    return <div />
+>div : Symbol(JSX.IntrinsicElements.div, Decl(react16.d.ts, 2546, 114))
+}
+
+function Test<T extends 'button' | 'a'>(el: T) {
+>Test : Symbol(Test, Decl(jsxIntrinsicElementsCompatability.tsx, 5, 1))
+>T : Symbol(T, Decl(jsxIntrinsicElementsCompatability.tsx, 7, 14))
+>el : Symbol(el, Decl(jsxIntrinsicElementsCompatability.tsx, 7, 40))
+>T : Symbol(T, Decl(jsxIntrinsicElementsCompatability.tsx, 7, 14))
+
+    return <SomeComponent element={el} />
+>SomeComponent : Symbol(SomeComponent, Decl(jsxIntrinsicElementsCompatability.tsx, 1, 31))
+>element : Symbol(element, Decl(jsxIntrinsicElementsCompatability.tsx, 8, 25))
+>el : Symbol(el, Decl(jsxIntrinsicElementsCompatability.tsx, 7, 40))
+}
diff --git a/tests/baselines/reference/jsxIntrinsicElementsCompatability.types b/tests/baselines/reference/jsxIntrinsicElementsCompatability.types
new file mode 100644
index 0000000000000..e0479dae19e78
--- /dev/null
+++ b/tests/baselines/reference/jsxIntrinsicElementsCompatability.types
@@ -0,0 +1,28 @@
+=== tests/cases/compiler/jsxIntrinsicElementsCompatability.tsx ===
+/// <reference path="react16.d.ts" />
+import * as React from "react";
+>React : typeof React
+
+function SomeComponent<T extends 'button' | 'a'>(props: { element?: T } & JSX.IntrinsicElements[T]): JSX.Element {
+>SomeComponent : <T extends "a" | "button">(props: {    element?: T;} & JSX.IntrinsicElements[T]) => JSX.Element
+>props : { element?: T | undefined; } & JSX.IntrinsicElements[T]
+>element : T | undefined
+>JSX : any
+>JSX : any
+
+    // Just so the return value is RectElement, the rendered element doesnt matter
+    return <div />
+><div /> : JSX.Element
+>div : any
+}
+
+function Test<T extends 'button' | 'a'>(el: T) {
+>Test : <T extends "a" | "button">(el: T) => JSX.Element
+>el : T
+
+    return <SomeComponent element={el} />
+><SomeComponent element={el} /> : JSX.Element
+>SomeComponent : <T extends "a" | "button">(props: { element?: T | undefined; } & JSX.IntrinsicElements[T]) => JSX.Element
+>element : T
+>el : T
+}
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=node16).errors.txt b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).errors.txt
new file mode 100644
index 0000000000000..f90724d92338b
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).errors.txt
@@ -0,0 +1,64 @@
+tests/cases/compiler/b.mts(15,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(16,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(17,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(18,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(19,6): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(20,6): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+
+
+==== tests/cases/compiler/mod.cts (0 errors) ====
+    declare function fun(): void;
+    export default fun;
+==== tests/cases/compiler/b.mts (6 errors) ====
+    import a from "./mod.cjs";
+    import { default as b } from "./mod.cjs";
+    import c, { default as d } from "./mod.cjs";
+    import * as self from "./b.mjs";
+    export { default } from "./mod.cjs";
+    export { default as def } from "./mod.cjs";
+    
+    a === b;
+    b === c;
+    c === d;
+    d === self.default;
+    self.default === self.def;
+    
+    // should all fail
+    a();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    b();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    c();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    d();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    self.default();
+         ~~~~~~~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    self.def();
+         ~~~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    
+    // should all work
+    a.default();
+    b.default();
+    c.default();
+    d.default();
+    self.default.default();
+    self.def.default();
\ No newline at end of file
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=node16).js b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).js
new file mode 100644
index 0000000000000..1d6e31ec0afb2
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).js
@@ -0,0 +1,65 @@
+//// [tests/cases/compiler/moduleNodeDefaultImports.ts] ////
+
+//// [mod.cts]
+declare function fun(): void;
+export default fun;
+//// [b.mts]
+import a from "./mod.cjs";
+import { default as b } from "./mod.cjs";
+import c, { default as d } from "./mod.cjs";
+import * as self from "./b.mjs";
+export { default } from "./mod.cjs";
+export { default as def } from "./mod.cjs";
+
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
+
+//// [mod.cjs]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.default = fun;
+//// [b.mjs]
+import a from "./mod.cjs";
+import { default as b } from "./mod.cjs";
+import c, { default as d } from "./mod.cjs";
+import * as self from "./b.mjs";
+export { default } from "./mod.cjs";
+export { default as def } from "./mod.cjs";
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=node16).symbols b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).symbols
new file mode 100644
index 0000000000000..7d475bb0e7e6a
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).symbols
@@ -0,0 +1,114 @@
+=== tests/cases/compiler/mod.cts ===
+declare function fun(): void;
+>fun : Symbol(fun, Decl(mod.cts, 0, 0))
+
+export default fun;
+>fun : Symbol(fun, Decl(mod.cts, 0, 0))
+
+=== tests/cases/compiler/b.mts ===
+import a from "./mod.cjs";
+>a : Symbol(a, Decl(b.mts, 0, 6))
+
+import { default as b } from "./mod.cjs";
+>default : Symbol(a, Decl(mod.cts, 0, 0))
+>b : Symbol(b, Decl(b.mts, 1, 8))
+
+import c, { default as d } from "./mod.cjs";
+>c : Symbol(c, Decl(b.mts, 2, 6))
+>default : Symbol(a, Decl(mod.cts, 0, 0))
+>d : Symbol(d, Decl(b.mts, 2, 11))
+
+import * as self from "./b.mjs";
+>self : Symbol(self, Decl(b.mts, 3, 6))
+
+export { default } from "./mod.cjs";
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+
+export { default as def } from "./mod.cjs";
+>default : Symbol(a, Decl(mod.cts, 0, 0))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+
+a === b;
+>a : Symbol(a, Decl(b.mts, 0, 6))
+>b : Symbol(b, Decl(b.mts, 1, 8))
+
+b === c;
+>b : Symbol(b, Decl(b.mts, 1, 8))
+>c : Symbol(c, Decl(b.mts, 2, 6))
+
+c === d;
+>c : Symbol(c, Decl(b.mts, 2, 6))
+>d : Symbol(d, Decl(b.mts, 2, 11))
+
+d === self.default;
+>d : Symbol(d, Decl(b.mts, 2, 11))
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+
+self.default === self.def;
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self.def : Symbol(self.def, Decl(b.mts, 5, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+
+// should all fail
+a();
+>a : Symbol(a, Decl(b.mts, 0, 6))
+
+b();
+>b : Symbol(b, Decl(b.mts, 1, 8))
+
+c();
+>c : Symbol(c, Decl(b.mts, 2, 6))
+
+d();
+>d : Symbol(d, Decl(b.mts, 2, 11))
+
+self.default();
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+
+self.def();
+>self.def : Symbol(self.def, Decl(b.mts, 5, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+
+// should all work
+a.default();
+>a.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>a : Symbol(a, Decl(b.mts, 0, 6))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+b.default();
+>b.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>b : Symbol(b, Decl(b.mts, 1, 8))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+c.default();
+>c.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>c : Symbol(c, Decl(b.mts, 2, 6))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+d.default();
+>d.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>d : Symbol(d, Decl(b.mts, 2, 11))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+self.default.default();
+>self.default.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+self.def.default();
+>self.def.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>self.def : Symbol(self.def, Decl(b.mts, 5, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=node16).types b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).types
new file mode 100644
index 0000000000000..653dac121b8b0
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=node16).types
@@ -0,0 +1,131 @@
+=== tests/cases/compiler/mod.cts ===
+declare function fun(): void;
+>fun : () => void
+
+export default fun;
+>fun : () => void
+
+=== tests/cases/compiler/b.mts ===
+import a from "./mod.cjs";
+>a : typeof a
+
+import { default as b } from "./mod.cjs";
+>default : typeof a
+>b : typeof a
+
+import c, { default as d } from "./mod.cjs";
+>c : typeof a
+>default : typeof a
+>d : typeof a
+
+import * as self from "./b.mjs";
+>self : typeof self
+
+export { default } from "./mod.cjs";
+>default : typeof a
+
+export { default as def } from "./mod.cjs";
+>default : typeof a
+>def : typeof a
+
+a === b;
+>a === b : boolean
+>a : typeof a
+>b : typeof a
+
+b === c;
+>b === c : boolean
+>b : typeof a
+>c : typeof a
+
+c === d;
+>c === d : boolean
+>c : typeof a
+>d : typeof a
+
+d === self.default;
+>d === self.default : boolean
+>d : typeof a
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+
+self.default === self.def;
+>self.default === self.def : boolean
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+
+// should all fail
+a();
+>a() : any
+>a : typeof a
+
+b();
+>b() : any
+>b : typeof a
+
+c();
+>c() : any
+>c : typeof a
+
+d();
+>d() : any
+>d : typeof a
+
+self.default();
+>self.default() : any
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+
+self.def();
+>self.def() : any
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+
+// should all work
+a.default();
+>a.default() : void
+>a.default : () => void
+>a : typeof a
+>default : () => void
+
+b.default();
+>b.default() : void
+>b.default : () => void
+>b : typeof a
+>default : () => void
+
+c.default();
+>c.default() : void
+>c.default : () => void
+>c : typeof a
+>default : () => void
+
+d.default();
+>d.default() : void
+>d.default : () => void
+>d : typeof a
+>default : () => void
+
+self.default.default();
+>self.default.default() : void
+>self.default.default : () => void
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+>default : () => void
+
+self.def.default();
+>self.def.default() : void
+>self.def.default : () => void
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+>default : () => void
+
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).errors.txt b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).errors.txt
new file mode 100644
index 0000000000000..f90724d92338b
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).errors.txt
@@ -0,0 +1,64 @@
+tests/cases/compiler/b.mts(15,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(16,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(17,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(18,1): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(19,6): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+tests/cases/compiler/b.mts(20,6): error TS2349: This expression is not callable.
+  Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+
+
+==== tests/cases/compiler/mod.cts (0 errors) ====
+    declare function fun(): void;
+    export default fun;
+==== tests/cases/compiler/b.mts (6 errors) ====
+    import a from "./mod.cjs";
+    import { default as b } from "./mod.cjs";
+    import c, { default as d } from "./mod.cjs";
+    import * as self from "./b.mjs";
+    export { default } from "./mod.cjs";
+    export { default as def } from "./mod.cjs";
+    
+    a === b;
+    b === c;
+    c === d;
+    d === self.default;
+    self.default === self.def;
+    
+    // should all fail
+    a();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    b();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    c();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    d();
+    ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    self.default();
+         ~~~~~~~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    self.def();
+         ~~~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type 'typeof import("tests/cases/compiler/mod")' has no call signatures.
+    
+    // should all work
+    a.default();
+    b.default();
+    c.default();
+    d.default();
+    self.default.default();
+    self.def.default();
\ No newline at end of file
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).js b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).js
new file mode 100644
index 0000000000000..1d6e31ec0afb2
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).js
@@ -0,0 +1,65 @@
+//// [tests/cases/compiler/moduleNodeDefaultImports.ts] ////
+
+//// [mod.cts]
+declare function fun(): void;
+export default fun;
+//// [b.mts]
+import a from "./mod.cjs";
+import { default as b } from "./mod.cjs";
+import c, { default as d } from "./mod.cjs";
+import * as self from "./b.mjs";
+export { default } from "./mod.cjs";
+export { default as def } from "./mod.cjs";
+
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
+
+//// [mod.cjs]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.default = fun;
+//// [b.mjs]
+import a from "./mod.cjs";
+import { default as b } from "./mod.cjs";
+import c, { default as d } from "./mod.cjs";
+import * as self from "./b.mjs";
+export { default } from "./mod.cjs";
+export { default as def } from "./mod.cjs";
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).symbols b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).symbols
new file mode 100644
index 0000000000000..7d475bb0e7e6a
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).symbols
@@ -0,0 +1,114 @@
+=== tests/cases/compiler/mod.cts ===
+declare function fun(): void;
+>fun : Symbol(fun, Decl(mod.cts, 0, 0))
+
+export default fun;
+>fun : Symbol(fun, Decl(mod.cts, 0, 0))
+
+=== tests/cases/compiler/b.mts ===
+import a from "./mod.cjs";
+>a : Symbol(a, Decl(b.mts, 0, 6))
+
+import { default as b } from "./mod.cjs";
+>default : Symbol(a, Decl(mod.cts, 0, 0))
+>b : Symbol(b, Decl(b.mts, 1, 8))
+
+import c, { default as d } from "./mod.cjs";
+>c : Symbol(c, Decl(b.mts, 2, 6))
+>default : Symbol(a, Decl(mod.cts, 0, 0))
+>d : Symbol(d, Decl(b.mts, 2, 11))
+
+import * as self from "./b.mjs";
+>self : Symbol(self, Decl(b.mts, 3, 6))
+
+export { default } from "./mod.cjs";
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+
+export { default as def } from "./mod.cjs";
+>default : Symbol(a, Decl(mod.cts, 0, 0))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+
+a === b;
+>a : Symbol(a, Decl(b.mts, 0, 6))
+>b : Symbol(b, Decl(b.mts, 1, 8))
+
+b === c;
+>b : Symbol(b, Decl(b.mts, 1, 8))
+>c : Symbol(c, Decl(b.mts, 2, 6))
+
+c === d;
+>c : Symbol(c, Decl(b.mts, 2, 6))
+>d : Symbol(d, Decl(b.mts, 2, 11))
+
+d === self.default;
+>d : Symbol(d, Decl(b.mts, 2, 11))
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+
+self.default === self.def;
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self.def : Symbol(self.def, Decl(b.mts, 5, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+
+// should all fail
+a();
+>a : Symbol(a, Decl(b.mts, 0, 6))
+
+b();
+>b : Symbol(b, Decl(b.mts, 1, 8))
+
+c();
+>c : Symbol(c, Decl(b.mts, 2, 6))
+
+d();
+>d : Symbol(d, Decl(b.mts, 2, 11))
+
+self.default();
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+
+self.def();
+>self.def : Symbol(self.def, Decl(b.mts, 5, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+
+// should all work
+a.default();
+>a.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>a : Symbol(a, Decl(b.mts, 0, 6))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+b.default();
+>b.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>b : Symbol(b, Decl(b.mts, 1, 8))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+c.default();
+>c.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>c : Symbol(c, Decl(b.mts, 2, 6))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+d.default();
+>d.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>d : Symbol(d, Decl(b.mts, 2, 11))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+self.default.default();
+>self.default.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>self.default : Symbol(self.default, Decl(b.mts, 4, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>default : Symbol(self.default, Decl(b.mts, 4, 8))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
+self.def.default();
+>self.def.default : Symbol(a.default, Decl(mod.cts, 0, 29))
+>self.def : Symbol(self.def, Decl(b.mts, 5, 8))
+>self : Symbol(self, Decl(b.mts, 3, 6))
+>def : Symbol(self.def, Decl(b.mts, 5, 8))
+>default : Symbol(a.default, Decl(mod.cts, 0, 29))
+
diff --git a/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).types b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).types
new file mode 100644
index 0000000000000..653dac121b8b0
--- /dev/null
+++ b/tests/baselines/reference/moduleNodeDefaultImports(module=nodenext).types
@@ -0,0 +1,131 @@
+=== tests/cases/compiler/mod.cts ===
+declare function fun(): void;
+>fun : () => void
+
+export default fun;
+>fun : () => void
+
+=== tests/cases/compiler/b.mts ===
+import a from "./mod.cjs";
+>a : typeof a
+
+import { default as b } from "./mod.cjs";
+>default : typeof a
+>b : typeof a
+
+import c, { default as d } from "./mod.cjs";
+>c : typeof a
+>default : typeof a
+>d : typeof a
+
+import * as self from "./b.mjs";
+>self : typeof self
+
+export { default } from "./mod.cjs";
+>default : typeof a
+
+export { default as def } from "./mod.cjs";
+>default : typeof a
+>def : typeof a
+
+a === b;
+>a === b : boolean
+>a : typeof a
+>b : typeof a
+
+b === c;
+>b === c : boolean
+>b : typeof a
+>c : typeof a
+
+c === d;
+>c === d : boolean
+>c : typeof a
+>d : typeof a
+
+d === self.default;
+>d === self.default : boolean
+>d : typeof a
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+
+self.default === self.def;
+>self.default === self.def : boolean
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+
+// should all fail
+a();
+>a() : any
+>a : typeof a
+
+b();
+>b() : any
+>b : typeof a
+
+c();
+>c() : any
+>c : typeof a
+
+d();
+>d() : any
+>d : typeof a
+
+self.default();
+>self.default() : any
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+
+self.def();
+>self.def() : any
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+
+// should all work
+a.default();
+>a.default() : void
+>a.default : () => void
+>a : typeof a
+>default : () => void
+
+b.default();
+>b.default() : void
+>b.default : () => void
+>b : typeof a
+>default : () => void
+
+c.default();
+>c.default() : void
+>c.default : () => void
+>c : typeof a
+>default : () => void
+
+d.default();
+>d.default() : void
+>d.default : () => void
+>d : typeof a
+>default : () => void
+
+self.default.default();
+>self.default.default() : void
+>self.default.default : () => void
+>self.default : typeof a
+>self : typeof self
+>default : typeof a
+>default : () => void
+
+self.def.default();
+>self.def.default() : void
+>self.def.default : () => void
+>self.def : typeof a
+>self : typeof self
+>def : typeof a
+>default : () => void
+
diff --git a/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).js b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).js
new file mode 100644
index 0000000000000..1ac2c23d4a83a
--- /dev/null
+++ b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).js
@@ -0,0 +1,21 @@
+//// [nonNullableAndObjectIntersections.ts]
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+type T1 = NonNullable<undefined>;
+type T2 = null & {};
+type T3 = undefined & {};
+type T4 = null & undefined;
+type T6 = null & { a: string } & {};
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+
+type TestNew = NonNullableNew<null>;
+type TestOld = NonNullableOld<null>;
+
+
+//// [nonNullableAndObjectIntersections.js]
+// These should all resolve to never
diff --git a/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).symbols b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).symbols
new file mode 100644
index 0000000000000..1d4558399dbbf
--- /dev/null
+++ b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).symbols
@@ -0,0 +1,45 @@
+=== tests/cases/compiler/nonNullableAndObjectIntersections.ts ===
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+>T0 : Symbol(T0, Decl(nonNullableAndObjectIntersections.ts, 0, 0))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+
+type T1 = NonNullable<undefined>;
+>T1 : Symbol(T1, Decl(nonNullableAndObjectIntersections.ts, 2, 28))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+
+type T2 = null & {};
+>T2 : Symbol(T2, Decl(nonNullableAndObjectIntersections.ts, 3, 33))
+
+type T3 = undefined & {};
+>T3 : Symbol(T3, Decl(nonNullableAndObjectIntersections.ts, 4, 20))
+
+type T4 = null & undefined;
+>T4 : Symbol(T4, Decl(nonNullableAndObjectIntersections.ts, 5, 25))
+
+type T6 = null & { a: string } & {};
+>T6 : Symbol(T6, Decl(nonNullableAndObjectIntersections.ts, 6, 27))
+>a : Symbol(a, Decl(nonNullableAndObjectIntersections.ts, 7, 18))
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+>NonNullableNew : Symbol(NonNullableNew, Decl(nonNullableAndObjectIntersections.ts, 7, 36))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 11, 20))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 11, 20))
+
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+>NonNullableOld : Symbol(NonNullableOld, Decl(nonNullableAndObjectIntersections.ts, 11, 32))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 12, 20))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 12, 20))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 12, 20))
+
+type TestNew = NonNullableNew<null>;
+>TestNew : Symbol(TestNew, Decl(nonNullableAndObjectIntersections.ts, 12, 64))
+>NonNullableNew : Symbol(NonNullableNew, Decl(nonNullableAndObjectIntersections.ts, 7, 36))
+
+type TestOld = NonNullableOld<null>;
+>TestOld : Symbol(TestOld, Decl(nonNullableAndObjectIntersections.ts, 14, 36))
+>NonNullableOld : Symbol(NonNullableOld, Decl(nonNullableAndObjectIntersections.ts, 11, 32))
+
diff --git a/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).types b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).types
new file mode 100644
index 0000000000000..19b4e9c5f06e7
--- /dev/null
+++ b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=false).types
@@ -0,0 +1,43 @@
+=== tests/cases/compiler/nonNullableAndObjectIntersections.ts ===
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+>T0 : never
+>null : null
+
+type T1 = NonNullable<undefined>;
+>T1 : never
+
+type T2 = null & {};
+>T2 : never
+>null : null
+
+type T3 = undefined & {};
+>T3 : never
+
+type T4 = null & undefined;
+>T4 : never
+>null : null
+
+type T6 = null & { a: string } & {};
+>T6 : never
+>null : null
+>a : string
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+>NonNullableNew : NonNullableNew<T>
+
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+>NonNullableOld : NonNullableOld<T>
+>null : null
+
+type TestNew = NonNullableNew<null>;
+>TestNew : never
+>null : null
+
+type TestOld = NonNullableOld<null>;
+>TestOld : never
+>null : null
+
diff --git a/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).js b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).js
new file mode 100644
index 0000000000000..51b88571c735e
--- /dev/null
+++ b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).js
@@ -0,0 +1,22 @@
+//// [nonNullableAndObjectIntersections.ts]
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+type T1 = NonNullable<undefined>;
+type T2 = null & {};
+type T3 = undefined & {};
+type T4 = null & undefined;
+type T6 = null & { a: string } & {};
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+
+type TestNew = NonNullableNew<null>;
+type TestOld = NonNullableOld<null>;
+
+
+//// [nonNullableAndObjectIntersections.js]
+"use strict";
+// These should all resolve to never
diff --git a/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).symbols b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).symbols
new file mode 100644
index 0000000000000..1d4558399dbbf
--- /dev/null
+++ b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).symbols
@@ -0,0 +1,45 @@
+=== tests/cases/compiler/nonNullableAndObjectIntersections.ts ===
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+>T0 : Symbol(T0, Decl(nonNullableAndObjectIntersections.ts, 0, 0))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+
+type T1 = NonNullable<undefined>;
+>T1 : Symbol(T1, Decl(nonNullableAndObjectIntersections.ts, 2, 28))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+
+type T2 = null & {};
+>T2 : Symbol(T2, Decl(nonNullableAndObjectIntersections.ts, 3, 33))
+
+type T3 = undefined & {};
+>T3 : Symbol(T3, Decl(nonNullableAndObjectIntersections.ts, 4, 20))
+
+type T4 = null & undefined;
+>T4 : Symbol(T4, Decl(nonNullableAndObjectIntersections.ts, 5, 25))
+
+type T6 = null & { a: string } & {};
+>T6 : Symbol(T6, Decl(nonNullableAndObjectIntersections.ts, 6, 27))
+>a : Symbol(a, Decl(nonNullableAndObjectIntersections.ts, 7, 18))
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+>NonNullableNew : Symbol(NonNullableNew, Decl(nonNullableAndObjectIntersections.ts, 7, 36))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 11, 20))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 11, 20))
+
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+>NonNullableOld : Symbol(NonNullableOld, Decl(nonNullableAndObjectIntersections.ts, 11, 32))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 12, 20))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 12, 20))
+>T : Symbol(T, Decl(nonNullableAndObjectIntersections.ts, 12, 20))
+
+type TestNew = NonNullableNew<null>;
+>TestNew : Symbol(TestNew, Decl(nonNullableAndObjectIntersections.ts, 12, 64))
+>NonNullableNew : Symbol(NonNullableNew, Decl(nonNullableAndObjectIntersections.ts, 7, 36))
+
+type TestOld = NonNullableOld<null>;
+>TestOld : Symbol(TestOld, Decl(nonNullableAndObjectIntersections.ts, 14, 36))
+>NonNullableOld : Symbol(NonNullableOld, Decl(nonNullableAndObjectIntersections.ts, 11, 32))
+
diff --git a/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).types b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).types
new file mode 100644
index 0000000000000..19b4e9c5f06e7
--- /dev/null
+++ b/tests/baselines/reference/nonNullableAndObjectIntersections(strict=true).types
@@ -0,0 +1,43 @@
+=== tests/cases/compiler/nonNullableAndObjectIntersections.ts ===
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+>T0 : never
+>null : null
+
+type T1 = NonNullable<undefined>;
+>T1 : never
+
+type T2 = null & {};
+>T2 : never
+>null : null
+
+type T3 = undefined & {};
+>T3 : never
+
+type T4 = null & undefined;
+>T4 : never
+>null : null
+
+type T6 = null & { a: string } & {};
+>T6 : never
+>null : null
+>a : string
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+>NonNullableNew : NonNullableNew<T>
+
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+>NonNullableOld : NonNullableOld<T>
+>null : null
+
+type TestNew = NonNullableNew<null>;
+>TestNew : never
+>null : null
+
+type TestOld = NonNullableOld<null>;
+>TestOld : never
+>null : null
+
diff --git a/tests/baselines/reference/nonNullableWithNullableGenericIndexedAccessArg.symbols b/tests/baselines/reference/nonNullableWithNullableGenericIndexedAccessArg.symbols
new file mode 100644
index 0000000000000..a461d361eedcc
--- /dev/null
+++ b/tests/baselines/reference/nonNullableWithNullableGenericIndexedAccessArg.symbols
@@ -0,0 +1,77 @@
+=== tests/cases/compiler/nonNullableWithNullableGenericIndexedAccessArg.ts ===
+// repro from #50539
+
+interface StateSchema {
+>StateSchema : Symbol(StateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 0, 0))
+
+  states?: {
+>states : Symbol(StateSchema.states, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 2, 23))
+
+    [key: string]: StateSchema;
+>key : Symbol(key, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 4, 5))
+>StateSchema : Symbol(StateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 0, 0))
+
+  };
+}
+
+declare class StateNode<TStateSchema extends StateSchema> {
+>StateNode : Symbol(StateNode, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 6, 1))
+>TStateSchema : Symbol(TStateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 8, 24))
+>StateSchema : Symbol(StateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 0, 0))
+
+  schema: TStateSchema;
+>schema : Symbol(StateNode.schema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 8, 59))
+>TStateSchema : Symbol(TStateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 8, 24))
+}
+
+type StateNodesConfig<TStateSchema extends StateSchema> = {
+>StateNodesConfig : Symbol(StateNodesConfig, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 10, 1))
+>TStateSchema : Symbol(TStateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 12, 22))
+>StateSchema : Symbol(StateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 0, 0))
+
+  [K in keyof TStateSchema["states"]]: StateNode<NonNullable<TStateSchema["states"]>[K]>;
+>K : Symbol(K, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 13, 3))
+>TStateSchema : Symbol(TStateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 12, 22))
+>StateNode : Symbol(StateNode, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 6, 1))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+>TStateSchema : Symbol(TStateSchema, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 12, 22))
+>K : Symbol(K, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 13, 3))
+
+};
+
+// repro from #50539#issuecomment-1234067835
+
+type Ordering<TOrderBy extends string> = {
+>Ordering : Symbol(Ordering, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 14, 2))
+>TOrderBy : Symbol(TOrderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 18, 14))
+
+    orderBy: TOrderBy
+>orderBy : Symbol(orderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 18, 42))
+>TOrderBy : Symbol(TOrderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 18, 14))
+}
+
+type Query<TOrderBy extends string> = {
+>Query : Symbol(Query, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 20, 1))
+>TOrderBy : Symbol(TOrderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 22, 11))
+
+    order?: Ordering<TOrderBy>
+>order : Symbol(order, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 22, 39))
+>Ordering : Symbol(Ordering, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 14, 2))
+>TOrderBy : Symbol(TOrderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 22, 11))
+}
+
+type QueryHandler<
+>QueryHandler : Symbol(QueryHandler, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 24, 1))
+
+    TQuery extends Query<TOrderBy>,
+>TQuery : Symbol(TQuery, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 26, 18))
+>Query : Symbol(Query, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 20, 1))
+>TOrderBy : Symbol(TOrderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 27, 35))
+
+    TOrderBy extends string = NonNullable<TQuery["order"]>["orderBy"]
+>TOrderBy : Symbol(TOrderBy, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 27, 35))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+>TQuery : Symbol(TQuery, Decl(nonNullableWithNullableGenericIndexedAccessArg.ts, 26, 18))
+
+> = {}
+
diff --git a/tests/baselines/reference/nonNullableWithNullableGenericIndexedAccessArg.types b/tests/baselines/reference/nonNullableWithNullableGenericIndexedAccessArg.types
new file mode 100644
index 0000000000000..f2bbff47ada4c
--- /dev/null
+++ b/tests/baselines/reference/nonNullableWithNullableGenericIndexedAccessArg.types
@@ -0,0 +1,49 @@
+=== tests/cases/compiler/nonNullableWithNullableGenericIndexedAccessArg.ts ===
+// repro from #50539
+
+interface StateSchema {
+  states?: {
+>states : { [key: string]: StateSchema; } | undefined
+
+    [key: string]: StateSchema;
+>key : string
+
+  };
+}
+
+declare class StateNode<TStateSchema extends StateSchema> {
+>StateNode : StateNode<TStateSchema>
+
+  schema: TStateSchema;
+>schema : TStateSchema
+}
+
+type StateNodesConfig<TStateSchema extends StateSchema> = {
+>StateNodesConfig : StateNodesConfig<TStateSchema>
+
+  [K in keyof TStateSchema["states"]]: StateNode<NonNullable<TStateSchema["states"]>[K]>;
+};
+
+// repro from #50539#issuecomment-1234067835
+
+type Ordering<TOrderBy extends string> = {
+>Ordering : Ordering<TOrderBy>
+
+    orderBy: TOrderBy
+>orderBy : TOrderBy
+}
+
+type Query<TOrderBy extends string> = {
+>Query : Query<TOrderBy>
+
+    order?: Ordering<TOrderBy>
+>order : Ordering<TOrderBy> | undefined
+}
+
+type QueryHandler<
+>QueryHandler : QueryHandler<TQuery, TOrderBy>
+
+    TQuery extends Query<TOrderBy>,
+    TOrderBy extends string = NonNullable<TQuery["order"]>["orderBy"]
+> = {}
+
diff --git a/tests/baselines/reference/tsbuild/containerOnlyReferenced/when-solution-is-referenced-indirectly.js b/tests/baselines/reference/tsbuild/containerOnlyReferenced/when-solution-is-referenced-indirectly.js
new file mode 100644
index 0000000000000..7cc61e7f319ee
--- /dev/null
+++ b/tests/baselines/reference/tsbuild/containerOnlyReferenced/when-solution-is-referenced-indirectly.js
@@ -0,0 +1,303 @@
+Input::
+//// [/lib/lib.d.ts]
+/// <reference no-default-lib="true"/>
+interface Boolean {}
+interface Function {}
+interface CallableFunction {}
+interface NewableFunction {}
+interface IArguments {}
+interface Number { toExponential: any; }
+interface Object {}
+interface RegExp {}
+interface String { charAt: any; }
+interface Array<T> { length: number; [n: number]: T; }
+interface ReadonlyArray<T> {}
+declare const console: { log(msg: any): void; };
+
+//// [/src/project1/tsconfig.json]
+{"compilerOptions":{"composite":true},"references":[]}
+
+//// [/src/project2/src/b.ts]
+export const b = 10;
+
+//// [/src/project2/tsconfig.json]
+{"compilerOptions":{"composite":true},"references":[]}
+
+//// [/src/project3/src/c.ts]
+export const c = 10;
+
+//// [/src/project3/tsconfig.json]
+{"compilerOptions":{"composite":true},"references":[{"path":"../project1"},{"path":"../project2"}]}
+
+//// [/src/project4/src/d.ts]
+export const d = 10;
+
+//// [/src/project4/tsconfig.json]
+{"compilerOptions":{"composite":true},"references":[{"path":"../project3"}]}
+
+
+
+Output::
+/lib/tsc --b /src/project4 --verbose --explainFiles
+[12:00:20 AM] Projects in this build: 
+    * src/project1/tsconfig.json
+    * src/project2/tsconfig.json
+    * src/project3/tsconfig.json
+    * src/project4/tsconfig.json
+
+[12:00:21 AM] Project 'src/project2/tsconfig.json' is out of date because output file 'src/project2/tsconfig.tsbuildinfo' does not exist
+
+[12:00:22 AM] Building project '/src/project2/tsconfig.json'...
+
+lib/lib.d.ts
+  Default library for target 'es3'
+src/project2/src/b.ts
+  Matched by default include pattern '**/*'
+[12:00:28 AM] Project 'src/project3/tsconfig.json' is out of date because output file 'src/project3/tsconfig.tsbuildinfo' does not exist
+
+[12:00:29 AM] Building project '/src/project3/tsconfig.json'...
+
+lib/lib.d.ts
+  Default library for target 'es3'
+src/project3/src/c.ts
+  Matched by default include pattern '**/*'
+[12:00:35 AM] Project 'src/project4/tsconfig.json' is out of date because output file 'src/project4/tsconfig.tsbuildinfo' does not exist
+
+[12:00:36 AM] Building project '/src/project4/tsconfig.json'...
+
+lib/lib.d.ts
+  Default library for target 'es3'
+src/project4/src/d.ts
+  Matched by default include pattern '**/*'
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project2/src/b.d.ts]
+export declare const b = 10;
+
+
+//// [/src/project2/src/b.js]
+"use strict";
+exports.__esModule = true;
+exports.b = void 0;
+exports.b = 10;
+
+
+//// [/src/project2/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./src/b.ts"],"fileInfos":[{"version":"3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };","affectsGlobalScope":true},{"version":"-13368947479-export const b = 10;","signature":"-1807916688-export declare const b = 10;\r\n"}],"options":{"composite":true},"referencedMap":[],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"./src/b.d.ts"},"version":"FakeTSVersion"}
+
+//// [/src/project2/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./src/b.ts"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "signature": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "affectsGlobalScope": true
+      },
+      "./src/b.ts": {
+        "version": "-13368947479-export const b = 10;",
+        "signature": "-1807916688-export declare const b = 10;\r\n"
+      }
+    },
+    "options": {
+      "composite": true
+    },
+    "referencedMap": {},
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      "./src/b.ts"
+    ],
+    "latestChangedDtsFile": "./src/b.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 832
+}
+
+//// [/src/project3/src/c.d.ts]
+export declare const c = 10;
+
+
+//// [/src/project3/src/c.js]
+"use strict";
+exports.__esModule = true;
+exports.c = void 0;
+exports.c = 10;
+
+
+//// [/src/project3/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./src/c.ts"],"fileInfos":[{"version":"3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };","affectsGlobalScope":true},{"version":"-12077479510-export const c = 10;","signature":"-4148571535-export declare const c = 10;\r\n"}],"options":{"composite":true},"referencedMap":[],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"./src/c.d.ts"},"version":"FakeTSVersion"}
+
+//// [/src/project3/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./src/c.ts"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "signature": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "affectsGlobalScope": true
+      },
+      "./src/c.ts": {
+        "version": "-12077479510-export const c = 10;",
+        "signature": "-4148571535-export declare const c = 10;\r\n"
+      }
+    },
+    "options": {
+      "composite": true
+    },
+    "referencedMap": {},
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      "./src/c.ts"
+    ],
+    "latestChangedDtsFile": "./src/c.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 832
+}
+
+//// [/src/project4/src/d.d.ts]
+export declare const d = 10;
+
+
+//// [/src/project4/src/d.js]
+"use strict";
+exports.__esModule = true;
+exports.d = void 0;
+exports.d = 10;
+
+
+//// [/src/project4/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./src/d.ts"],"fileInfos":[{"version":"3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };","affectsGlobalScope":true},{"version":"-10786011541-export const d = 10;","signature":"-6489226382-export declare const d = 10;\r\n"}],"options":{"composite":true},"referencedMap":[],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"./src/d.d.ts"},"version":"FakeTSVersion"}
+
+//// [/src/project4/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./src/d.ts"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "signature": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "affectsGlobalScope": true
+      },
+      "./src/d.ts": {
+        "version": "-10786011541-export const d = 10;",
+        "signature": "-6489226382-export declare const d = 10;\r\n"
+      }
+    },
+    "options": {
+      "composite": true
+    },
+    "referencedMap": {},
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      "./src/d.ts"
+    ],
+    "latestChangedDtsFile": "./src/d.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 832
+}
+
+
+
+Change:: modify project3 file
+Input::
+//// [/src/project3/src/c.ts]
+export const cc = 10;
+
+
+
+Output::
+/lib/tsc --b /src/project4 --verbose --explainFiles
+[12:00:43 AM] Projects in this build: 
+    * src/project1/tsconfig.json
+    * src/project2/tsconfig.json
+    * src/project3/tsconfig.json
+    * src/project4/tsconfig.json
+
+[12:00:44 AM] Project 'src/project2/tsconfig.json' is up to date because newest input 'src/project2/src/b.ts' is older than output 'src/project2/tsconfig.tsbuildinfo'
+
+[12:00:45 AM] Project 'src/project3/tsconfig.json' is out of date because output 'src/project3/tsconfig.tsbuildinfo' is older than input 'src/project3/src/c.ts'
+
+[12:00:46 AM] Building project '/src/project3/tsconfig.json'...
+
+lib/lib.d.ts
+  Default library for target 'es3'
+src/project3/src/c.ts
+  Matched by default include pattern '**/*'
+[12:00:52 AM] Project 'src/project4/tsconfig.json' is out of date because output 'src/project4/tsconfig.tsbuildinfo' is older than input 'src/project3'
+
+[12:00:53 AM] Building project '/src/project4/tsconfig.json'...
+
+[12:00:54 AM] Updating unchanged output timestamps of project '/src/project4/tsconfig.json'...
+
+lib/lib.d.ts
+  Default library for target 'es3'
+src/project4/src/d.ts
+  Matched by default include pattern '**/*'
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project3/src/c.d.ts]
+export declare const cc = 10;
+
+
+//// [/src/project3/src/c.js]
+"use strict";
+exports.__esModule = true;
+exports.cc = void 0;
+exports.cc = 10;
+
+
+//// [/src/project3/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./src/c.ts"],"fileInfos":[{"version":"3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };","affectsGlobalScope":true},{"version":"-12481904019-export const cc = 10;","signature":"-2519819788-export declare const cc = 10;\r\n"}],"options":{"composite":true},"referencedMap":[],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"./src/c.d.ts"},"version":"FakeTSVersion"}
+
+//// [/src/project3/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./src/c.ts"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "signature": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "affectsGlobalScope": true
+      },
+      "./src/c.ts": {
+        "version": "-12481904019-export const cc = 10;",
+        "signature": "-2519819788-export declare const cc = 10;\r\n"
+      }
+    },
+    "options": {
+      "composite": true
+    },
+    "referencedMap": {},
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      "./src/c.ts"
+    ],
+    "latestChangedDtsFile": "./src/c.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 834
+}
+
+//// [/src/project4/tsconfig.tsbuildinfo] file changed its modified time
diff --git a/tests/baselines/reference/tscWatch/forceConsistentCasingInFileNames/self-name-package-reference.js b/tests/baselines/reference/tscWatch/forceConsistentCasingInFileNames/self-name-package-reference.js
new file mode 100644
index 0000000000000..02b1358e97ad7
--- /dev/null
+++ b/tests/baselines/reference/tscWatch/forceConsistentCasingInFileNames/self-name-package-reference.js
@@ -0,0 +1,148 @@
+Input::
+//// [/Users/name/projects/web/package.json]
+{"name":"@this/package","type":"module","exports":{".":"./dist/index.js"}}
+
+//// [/Users/name/projects/web/index.ts]
+import * as me from "@this/package";
+me.thing();
+export function thing(): void {}
+
+
+//// [/Users/name/projects/web/tsconfig.json]
+{"compilerOptions":{"module":"nodenext","outDir":"./dist","declarationDir":"./types","composite":true,"forceConsistentCasingInFileNames":true,"traceResolution":true}}
+
+//// [/a/lib/lib.esnext.full.d.ts]
+/// <reference no-default-lib="true"/>
+interface Boolean {}
+interface Function {}
+interface CallableFunction {}
+interface NewableFunction {}
+interface IArguments {}
+interface Number { toExponential: any; }
+interface Object {}
+interface RegExp {}
+interface String { charAt: any; }
+interface Array<T> { length: number; [n: number]: T; }
+
+
+/a/lib/tsc.js -w --explainFiles
+Output::
+>> Screen clear
+[12:00:23 AM] Starting compilation in watch mode...
+
+Found 'package.json' at '/users/name/projects/web/package.json'.
+'package.json' does not have a 'typesVersions' field.
+======== Resolving module '@this/package' from '/Users/name/projects/web/index.ts'. ========
+Module resolution kind is not specified, using 'NodeNext'.
+File '/users/name/projects/web/package.json' exists according to earlier cached lookups.
+File '/Users/name/projects/web/index.ts' exist - use it as a name resolution result.
+Resolving real path for '/Users/name/projects/web/index.ts', result '/Users/name/projects/web/index.ts'.
+======== Module name '@this/package' was successfully resolved to '/Users/name/projects/web/index.ts'. ========
+File '/a/lib/package.json' does not exist.
+File '/a/package.json' does not exist.
+File '/package.json' does not exist.
+../../../../a/lib/lib.esnext.full.d.ts
+  Default library for target 'esnext'
+index.ts
+  Matched by default include pattern '**/*'
+  Imported via "@this/package" from file 'index.ts'
+  File is ECMAScript module because 'package.json' has field "type" with value "module"
+[12:00:36 AM] Found 0 errors. Watching for file changes.
+
+
+
+Program root files: ["/Users/name/projects/web/index.ts"]
+Program options: {"module":199,"outDir":"/Users/name/projects/web/dist","declarationDir":"/Users/name/projects/web/types","composite":true,"forceConsistentCasingInFileNames":true,"traceResolution":true,"watch":true,"explainFiles":true,"configFilePath":"/Users/name/projects/web/tsconfig.json"}
+Program structureReused: Not
+Program files::
+/a/lib/lib.esnext.full.d.ts
+/Users/name/projects/web/index.ts
+
+Semantic diagnostics in builder refreshed for::
+/a/lib/lib.esnext.full.d.ts
+/Users/name/projects/web/index.ts
+
+Shape signatures in builder refreshed for::
+/a/lib/lib.esnext.full.d.ts (used version)
+/users/name/projects/web/index.ts (computed .d.ts during emit)
+
+WatchedFiles::
+/users/name/projects/web/tsconfig.json:
+  {"fileName":"/Users/name/projects/web/tsconfig.json","pollingInterval":250}
+/users/name/projects/web/index.ts:
+  {"fileName":"/Users/name/projects/web/index.ts","pollingInterval":250}
+/a/lib/lib.esnext.full.d.ts:
+  {"fileName":"/a/lib/lib.esnext.full.d.ts","pollingInterval":250}
+/users/name/projects/web/package.json:
+  {"fileName":"/Users/name/projects/web/package.json","pollingInterval":250}
+/users/name/projects/web/node_modules/@types:
+  {"fileName":"/Users/name/projects/web/node_modules/@types","pollingInterval":500}
+
+FsWatches::
+
+FsWatchesRecursive::
+/users/name/projects/web:
+  {"directoryName":"/users/name/projects/web"}
+
+exitCode:: ExitStatus.undefined
+
+//// [/Users/name/projects/web/dist/index.js]
+import * as me from "@this/package";
+me.thing();
+export function thing() { }
+
+
+//// [/Users/name/projects/web/types/index.d.ts]
+export declare function thing(): void;
+
+
+//// [/Users/name/projects/web/dist/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../../../../a/lib/lib.esnext.full.d.ts","../index.ts"],"fileInfos":[{"version":"-7698705165-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }","affectsGlobalScope":true,"impliedFormat":1},{"version":"14361483761-import * as me from \"@this/package\";\nme.thing();\nexport function thing(): void {}\n","signature":"-2724770439-export declare function thing(): void;\n","impliedFormat":99}],"options":{"composite":true,"declarationDir":"../types","module":199,"outDir":"./"},"fileIdsList":[[2]],"referencedMap":[[2,1]],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"../types/index.d.ts"},"version":"FakeTSVersion"}
+
+//// [/Users/name/projects/web/dist/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../../../../a/lib/lib.esnext.full.d.ts",
+      "../index.ts"
+    ],
+    "fileNamesList": [
+      [
+        "../index.ts"
+      ]
+    ],
+    "fileInfos": {
+      "../../../../../a/lib/lib.esnext.full.d.ts": {
+        "version": "-7698705165-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }",
+        "signature": "-7698705165-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }",
+        "affectsGlobalScope": true,
+        "impliedFormat": "commonjs"
+      },
+      "../index.ts": {
+        "version": "14361483761-import * as me from \"@this/package\";\nme.thing();\nexport function thing(): void {}\n",
+        "signature": "-2724770439-export declare function thing(): void;\n",
+        "impliedFormat": "esnext"
+      }
+    },
+    "options": {
+      "composite": true,
+      "declarationDir": "../types",
+      "module": 199,
+      "outDir": "./"
+    },
+    "referencedMap": {
+      "../index.ts": [
+        "../index.ts"
+      ]
+    },
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../../../../a/lib/lib.esnext.full.d.ts",
+      "../index.ts"
+    ],
+    "latestChangedDtsFile": "../types/index.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 974
+}
+
diff --git a/tests/baselines/reference/tscWatch/forceConsistentCasingInFileNames/with-nodeNext-resolution.js b/tests/baselines/reference/tscWatch/forceConsistentCasingInFileNames/with-nodeNext-resolution.js
new file mode 100644
index 0000000000000..efcf899a34ffa
--- /dev/null
+++ b/tests/baselines/reference/tscWatch/forceConsistentCasingInFileNames/with-nodeNext-resolution.js
@@ -0,0 +1,141 @@
+Input::
+//// [/Users/name/projects/web/src/bin.ts]
+import { foo } from "yargs";
+
+//// [/Users/name/projects/web/node_modules/@types/yargs/index.d.ts]
+export function foo(): void;
+
+//// [/Users/name/projects/web/node_modules/@types/yargs/index.d.mts]
+export function foo(): void;
+
+//// [/Users/name/projects/web/node_modules/@types/yargs/package.json]
+{"name":"yargs","version":"17.0.12","exports":{".":{"types":{"import":"./index.d.mts","default":"./index.d.ts"}}}}
+
+//// [/Users/name/projects/web/tsconfig.json]
+{"compilerOptions":{"moduleResolution":"nodenext","forceConsistentCasingInFileNames":true,"traceResolution":true}}
+
+//// [/a/lib/lib.d.ts]
+/// <reference no-default-lib="true"/>
+interface Boolean {}
+interface Function {}
+interface CallableFunction {}
+interface NewableFunction {}
+interface IArguments {}
+interface Number { toExponential: any; }
+interface Object {}
+interface RegExp {}
+interface String { charAt: any; }
+interface Array<T> { length: number; [n: number]: T; }
+
+
+/a/lib/tsc.js --w --explainFiles
+Output::
+>> Screen clear
+[12:00:35 AM] Starting compilation in watch mode...
+
+File '/users/name/projects/web/src/package.json' does not exist.
+File '/users/name/projects/web/package.json' does not exist.
+File '/users/name/projects/package.json' does not exist.
+File '/users/name/package.json' does not exist.
+File '/users/package.json' does not exist.
+File '/package.json' does not exist.
+======== Resolving module 'yargs' from '/Users/name/projects/web/src/bin.ts'. ========
+Explicitly specified module resolution kind: 'NodeNext'.
+File '/users/name/projects/web/src/package.json' does not exist according to earlier cached lookups.
+File '/users/name/projects/web/package.json' does not exist according to earlier cached lookups.
+File '/users/name/projects/package.json' does not exist according to earlier cached lookups.
+File '/users/name/package.json' does not exist according to earlier cached lookups.
+File '/users/package.json' does not exist according to earlier cached lookups.
+File '/package.json' does not exist according to earlier cached lookups.
+Loading module 'yargs' from 'node_modules' folder, target file type 'TypeScript'.
+Directory '/Users/name/projects/web/src/node_modules' does not exist, skipping all lookups in it.
+File '/Users/name/projects/web/node_modules/yargs.ts' does not exist.
+File '/Users/name/projects/web/node_modules/yargs.tsx' does not exist.
+File '/Users/name/projects/web/node_modules/yargs.d.ts' does not exist.
+Found 'package.json' at '/Users/name/projects/web/node_modules/@types/yargs/package.json'.
+'package.json' does not have a 'typesVersions' field.
+File '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts' exist - use it as a name resolution result.
+Resolving real path for '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts', result '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts'.
+======== Module name 'yargs' was successfully resolved to '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts' with Package ID 'yargs/index.d.ts@17.0.12'. ========
+File '/users/name/projects/web/node_modules/@types/yargs/package.json' exists according to earlier cached lookups.
+======== Resolving type reference directive 'yargs', containing file '/Users/name/projects/web/__inferred type names__.ts', root directory '/Users/name/projects/web/node_modules/@types'. ========
+Resolving with primary search path '/Users/name/projects/web/node_modules/@types'.
+File '/Users/name/projects/web/node_modules/@types/yargs/package.json' exists according to earlier cached lookups.
+'package.json' does not have a 'typings' field.
+'package.json' does not have a 'types' field.
+File '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts' exist - use it as a name resolution result.
+Resolving real path for '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts', result '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts'.
+======== Type reference directive 'yargs' was successfully resolved to '/Users/name/projects/web/node_modules/@types/yargs/index.d.ts' with Package ID 'yargs/index.d.ts@17.0.12', primary: true. ========
+File '/a/lib/package.json' does not exist.
+File '/a/package.json' does not exist.
+File '/package.json' does not exist according to earlier cached lookups.
+../../../../a/lib/lib.d.ts
+  Default library for target 'es3'
+node_modules/@types/yargs/index.d.ts
+  Imported via "yargs" from file 'src/bin.ts' with packageId 'yargs/index.d.ts@17.0.12'
+  Entry point for implicit type library 'yargs' with packageId 'yargs/index.d.ts@17.0.12'
+  File is CommonJS module because 'node_modules/@types/yargs/package.json' does not have field "type"
+src/bin.ts
+  Matched by default include pattern '**/*'
+  File is CommonJS module because 'package.json' was not found
+[12:00:38 AM] Found 0 errors. Watching for file changes.
+
+
+
+Program root files: ["/Users/name/projects/web/src/bin.ts"]
+Program options: {"moduleResolution":99,"forceConsistentCasingInFileNames":true,"traceResolution":true,"watch":true,"explainFiles":true,"configFilePath":"/Users/name/projects/web/tsconfig.json"}
+Program structureReused: Not
+Program files::
+/a/lib/lib.d.ts
+/Users/name/projects/web/node_modules/@types/yargs/index.d.ts
+/Users/name/projects/web/src/bin.ts
+
+Semantic diagnostics in builder refreshed for::
+/a/lib/lib.d.ts
+/Users/name/projects/web/node_modules/@types/yargs/index.d.ts
+/Users/name/projects/web/src/bin.ts
+
+Shape signatures in builder refreshed for::
+/a/lib/lib.d.ts (used version)
+/users/name/projects/web/node_modules/@types/yargs/index.d.ts (used version)
+/users/name/projects/web/src/bin.ts (used version)
+
+WatchedFiles::
+/users/name/projects/web/tsconfig.json:
+  {"fileName":"/Users/name/projects/web/tsconfig.json","pollingInterval":250}
+/users/name/projects/web/src/bin.ts:
+  {"fileName":"/Users/name/projects/web/src/bin.ts","pollingInterval":250}
+/users/name/projects/web/node_modules/@types/yargs/index.d.ts:
+  {"fileName":"/Users/name/projects/web/node_modules/@types/yargs/index.d.ts","pollingInterval":250}
+/a/lib/lib.d.ts:
+  {"fileName":"/a/lib/lib.d.ts","pollingInterval":250}
+/users/name/projects/web/node_modules/@types/yargs/package.json:
+  {"fileName":"/Users/name/projects/web/node_modules/@types/yargs/package.json","pollingInterval":250}
+/users/name/projects/web/src/package.json:
+  {"fileName":"/Users/name/projects/web/src/package.json","pollingInterval":250}
+/users/name/projects/web/package.json:
+  {"fileName":"/Users/name/projects/web/package.json","pollingInterval":250}
+/users/name/projects/package.json:
+  {"fileName":"/Users/name/projects/package.json","pollingInterval":250}
+
+FsWatches::
+/users/name/projects/web:
+  {"directoryName":"/Users/name/projects/web"}
+
+FsWatchesRecursive::
+/users/name/projects/web/src:
+  {"directoryName":"/users/name/projects/web/src"}
+/users/name/projects/web/node_modules:
+  {"directoryName":"/Users/name/projects/web/node_modules"}
+/users/name/projects/web/node_modules/@types:
+  {"directoryName":"/Users/name/projects/web/node_modules/@types"}
+/users/name/projects/web:
+  {"directoryName":"/users/name/projects/web"}
+
+exitCode:: ExitStatus.undefined
+
+//// [/Users/name/projects/web/src/bin.js]
+"use strict";
+exports.__esModule = true;
+
+
diff --git a/tests/baselines/reference/tscWatch/watchApi/verify-that-module-resolution-with-json-extension-works-when-returned-without-extension.js b/tests/baselines/reference/tscWatch/watchApi/verify-that-module-resolution-with-json-extension-works-when-returned-without-extension.js
index 8cf3621e0c5f0..0e85dbe7067f7 100644
--- a/tests/baselines/reference/tscWatch/watchApi/verify-that-module-resolution-with-json-extension-works-when-returned-without-extension.js
+++ b/tests/baselines/reference/tscWatch/watchApi/verify-that-module-resolution-with-json-extension-works-when-returned-without-extension.js
@@ -35,7 +35,7 @@ Output::
   settings.json:1:1
     1 {"content":"Print this"}
       ~
-    This module is declared with using 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
+    This module is declared with 'export =', and can only be used with a default import when using the 'esModuleInterop' flag.
 
 [12:00:26 AM] Found 1 error. Watching for file changes.
 
diff --git a/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).js b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).js
new file mode 100644
index 0000000000000..c30c4d6723deb
--- /dev/null
+++ b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).js
@@ -0,0 +1,23 @@
+//// [undefinedAsDiscriminantWithUnknown.ts]
+type S = 
+| { type: 'string', value: string } 
+| { type: 'number', value: number } 
+| { type: 'unknown', value: unknown }
+| { value: undefined };
+
+declare var s: S
+
+if (s.value !== undefined) {
+  s;
+}
+else {
+  s;
+}
+
+//// [undefinedAsDiscriminantWithUnknown.js]
+if (s.value !== undefined) {
+    s;
+}
+else {
+    s;
+}
diff --git a/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).symbols b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).symbols
new file mode 100644
index 0000000000000..13da7db0555c1
--- /dev/null
+++ b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).symbols
@@ -0,0 +1,36 @@
+=== tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts ===
+type S = 
+>S : Symbol(S, Decl(undefinedAsDiscriminantWithUnknown.ts, 0, 0))
+
+| { type: 'string', value: string } 
+>type : Symbol(type, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 3))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 19))
+
+| { type: 'number', value: number } 
+>type : Symbol(type, Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 3))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 19))
+
+| { type: 'unknown', value: unknown }
+>type : Symbol(type, Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 3))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 20))
+
+| { value: undefined };
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 4, 3))
+
+declare var s: S
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+>S : Symbol(S, Decl(undefinedAsDiscriminantWithUnknown.ts, 0, 0))
+
+if (s.value !== undefined) {
+>s.value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 20), Decl(undefinedAsDiscriminantWithUnknown.ts, 4, 3))
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 20), Decl(undefinedAsDiscriminantWithUnknown.ts, 4, 3))
+>undefined : Symbol(undefined)
+
+  s;
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+}
+else {
+  s;
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+}
diff --git a/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).types b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).types
new file mode 100644
index 0000000000000..af09de9d3d839
--- /dev/null
+++ b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=false).types
@@ -0,0 +1,36 @@
+=== tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts ===
+type S = 
+>S : { type: 'string'; value: string; } | { type: 'number'; value: number; } | { type: 'unknown'; value: unknown; } | { value: undefined; }
+
+| { type: 'string', value: string } 
+>type : "string"
+>value : string
+
+| { type: 'number', value: number } 
+>type : "number"
+>value : number
+
+| { type: 'unknown', value: unknown }
+>type : "unknown"
+>value : unknown
+
+| { value: undefined };
+>value : undefined
+
+declare var s: S
+>s : S
+
+if (s.value !== undefined) {
+>s.value !== undefined : boolean
+>s.value : unknown
+>s : S
+>value : unknown
+>undefined : undefined
+
+  s;
+>s : S
+}
+else {
+  s;
+>s : S
+}
diff --git a/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).js b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).js
new file mode 100644
index 0000000000000..c30c4d6723deb
--- /dev/null
+++ b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).js
@@ -0,0 +1,23 @@
+//// [undefinedAsDiscriminantWithUnknown.ts]
+type S = 
+| { type: 'string', value: string } 
+| { type: 'number', value: number } 
+| { type: 'unknown', value: unknown }
+| { value: undefined };
+
+declare var s: S
+
+if (s.value !== undefined) {
+  s;
+}
+else {
+  s;
+}
+
+//// [undefinedAsDiscriminantWithUnknown.js]
+if (s.value !== undefined) {
+    s;
+}
+else {
+    s;
+}
diff --git a/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).symbols b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).symbols
new file mode 100644
index 0000000000000..13da7db0555c1
--- /dev/null
+++ b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).symbols
@@ -0,0 +1,36 @@
+=== tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts ===
+type S = 
+>S : Symbol(S, Decl(undefinedAsDiscriminantWithUnknown.ts, 0, 0))
+
+| { type: 'string', value: string } 
+>type : Symbol(type, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 3))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 19))
+
+| { type: 'number', value: number } 
+>type : Symbol(type, Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 3))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 19))
+
+| { type: 'unknown', value: unknown }
+>type : Symbol(type, Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 3))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 20))
+
+| { value: undefined };
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 4, 3))
+
+declare var s: S
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+>S : Symbol(S, Decl(undefinedAsDiscriminantWithUnknown.ts, 0, 0))
+
+if (s.value !== undefined) {
+>s.value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 20), Decl(undefinedAsDiscriminantWithUnknown.ts, 4, 3))
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+>value : Symbol(value, Decl(undefinedAsDiscriminantWithUnknown.ts, 1, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 2, 19), Decl(undefinedAsDiscriminantWithUnknown.ts, 3, 20), Decl(undefinedAsDiscriminantWithUnknown.ts, 4, 3))
+>undefined : Symbol(undefined)
+
+  s;
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+}
+else {
+  s;
+>s : Symbol(s, Decl(undefinedAsDiscriminantWithUnknown.ts, 6, 11))
+}
diff --git a/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).types b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).types
new file mode 100644
index 0000000000000..69d640efe7337
--- /dev/null
+++ b/tests/baselines/reference/undefinedAsDiscriminantWithUnknown(strictnullchecks=true).types
@@ -0,0 +1,36 @@
+=== tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts ===
+type S = 
+>S : { type: 'string'; value: string; } | { type: 'number'; value: number; } | { type: 'unknown'; value: unknown; } | { value: undefined; }
+
+| { type: 'string', value: string } 
+>type : "string"
+>value : string
+
+| { type: 'number', value: number } 
+>type : "number"
+>value : number
+
+| { type: 'unknown', value: unknown }
+>type : "unknown"
+>value : unknown
+
+| { value: undefined };
+>value : undefined
+
+declare var s: S
+>s : S
+
+if (s.value !== undefined) {
+>s.value !== undefined : boolean
+>s.value : unknown
+>s : S
+>value : unknown
+>undefined : undefined
+
+  s;
+>s : { type: "string"; value: string; } | { type: "number"; value: number; } | { type: "unknown"; value: unknown; }
+}
+else {
+  s;
+>s : { type: "unknown"; value: unknown; } | { value: undefined; }
+}
diff --git a/tests/cases/compiler/emptyAnonymousObjectNarrowing.ts b/tests/cases/compiler/emptyAnonymousObjectNarrowing.ts
new file mode 100644
index 0000000000000..f37c3ee8c47fa
--- /dev/null
+++ b/tests/cases/compiler/emptyAnonymousObjectNarrowing.ts
@@ -0,0 +1,75 @@
+// @strictNullChecks: true,false
+
+declare let nonNull: {};
+if (nonNull === "foo") {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+declare let obj: { a: string };
+if (nonNull === obj) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+function f1<T>(x: T) {
+  if (nonNull === x) {
+    nonNull;
+  }
+  else {
+    nonNull;
+  }
+}
+
+function f2<T extends object>(x: T) {
+  if (nonNull === x) {
+    nonNull;
+  }
+  else {
+    nonNull;
+  }
+}
+
+declare let union: "xyz" | { a: string } | undefined;
+if (nonNull === union) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull === undefined) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull === null) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+if (nonNull == undefined) {
+  nonNull;
+}
+else {
+  nonNull;
+}
+
+// Repro from #50567
+const foo = (value: unknown): string => {
+  if (!value) {
+      return 'foo';
+  }
+  if (value === 'xyz') {
+      return value; // Type '{}' is not assignable to type 'string'.
+  }
+  return '';
+};
diff --git a/tests/cases/compiler/esModuleInteropDefaultImports.ts b/tests/cases/compiler/esModuleInteropDefaultImports.ts
new file mode 100644
index 0000000000000..0ddd2df567756
--- /dev/null
+++ b/tests/cases/compiler/esModuleInteropDefaultImports.ts
@@ -0,0 +1,36 @@
+// @esModuleInterop: true
+// @filename: mod.ts
+declare function fun(): void;
+export default fun;
+// @filename: a.ts
+import mod = require("./mod");
+export = mod;
+// @filename: b.ts
+import a from "./a";
+import { default as b } from "./a";
+import c, { default as d } from "./a";
+import * as self from "./b";
+export { default } from "./a";
+export { default as def } from "./a";
+
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
\ No newline at end of file
diff --git a/tests/cases/compiler/excessPropertyCheckingIntersectionWithConditional.ts b/tests/cases/compiler/excessPropertyCheckingIntersectionWithConditional.ts
new file mode 100644
index 0000000000000..c0e25cd85454e
--- /dev/null
+++ b/tests/cases/compiler/excessPropertyCheckingIntersectionWithConditional.ts
@@ -0,0 +1,4 @@
+type Foo<K> = K extends unknown ? { a: number } : unknown
+const createDefaultExample = <K,>(x: K): Foo<K> & { x: K; } => {
+  return { a: 1, x: x }; // okay in TS 4.7.4, error in TS 4.8.2
+}
\ No newline at end of file
diff --git a/tests/cases/compiler/inKeywordAndUnknown.ts b/tests/cases/compiler/inKeywordAndUnknown.ts
new file mode 100644
index 0000000000000..745dfbc1f9af5
--- /dev/null
+++ b/tests/cases/compiler/inKeywordAndUnknown.ts
@@ -0,0 +1,18 @@
+// @strict: true
+
+// Repro from #50531
+
+function f(x: {}, y: unknown) {
+    if (!("a" in x)) {
+        return;
+    }
+    x;  // {}
+    if (!y) {
+        return;
+    }
+    y;  // {}
+    if (!("a" in y)) {
+        return;
+    }
+    y;  // {}
+}
diff --git a/tests/cases/compiler/jsxIntrinsicElementsCompatability.tsx b/tests/cases/compiler/jsxIntrinsicElementsCompatability.tsx
new file mode 100644
index 0000000000000..faaec4fe77808
--- /dev/null
+++ b/tests/cases/compiler/jsxIntrinsicElementsCompatability.tsx
@@ -0,0 +1,12 @@
+// @strict: true
+// @jsx: react
+/// <reference path="/.lib/react16.d.ts" />
+import * as React from "react";
+function SomeComponent<T extends 'button' | 'a'>(props: { element?: T } & JSX.IntrinsicElements[T]): JSX.Element {
+    // Just so the return value is RectElement, the rendered element doesnt matter
+    return <div />
+}
+
+function Test<T extends 'button' | 'a'>(el: T) {
+    return <SomeComponent element={el} />
+}
\ No newline at end of file
diff --git a/tests/cases/compiler/moduleNodeDefaultImports.ts b/tests/cases/compiler/moduleNodeDefaultImports.ts
new file mode 100644
index 0000000000000..906de682bd610
--- /dev/null
+++ b/tests/cases/compiler/moduleNodeDefaultImports.ts
@@ -0,0 +1,33 @@
+// @module: node16,nodenext
+// @filename: mod.cts
+declare function fun(): void;
+export default fun;
+// @filename: b.mts
+import a from "./mod.cjs";
+import { default as b } from "./mod.cjs";
+import c, { default as d } from "./mod.cjs";
+import * as self from "./b.mjs";
+export { default } from "./mod.cjs";
+export { default as def } from "./mod.cjs";
+
+a === b;
+b === c;
+c === d;
+d === self.default;
+self.default === self.def;
+
+// should all fail
+a();
+b();
+c();
+d();
+self.default();
+self.def();
+
+// should all work
+a.default();
+b.default();
+c.default();
+d.default();
+self.default.default();
+self.def.default();
\ No newline at end of file
diff --git a/tests/cases/compiler/nonNullableAndObjectIntersections.ts b/tests/cases/compiler/nonNullableAndObjectIntersections.ts
new file mode 100644
index 0000000000000..a9e8319aef266
--- /dev/null
+++ b/tests/cases/compiler/nonNullableAndObjectIntersections.ts
@@ -0,0 +1,18 @@
+// @strict: true, false
+
+// These should all resolve to never
+
+type T0 = NonNullable<null>;
+type T1 = NonNullable<undefined>;
+type T2 = null & {};
+type T3 = undefined & {};
+type T4 = null & undefined;
+type T6 = null & { a: string } & {};
+
+// Repro from #50519
+
+type NonNullableNew<T> = T & {};
+type NonNullableOld<T> = T extends null | undefined ? never : T;
+
+type TestNew = NonNullableNew<null>;
+type TestOld = NonNullableOld<null>;
diff --git a/tests/cases/compiler/nonNullableWithNullableGenericIndexedAccessArg.ts b/tests/cases/compiler/nonNullableWithNullableGenericIndexedAccessArg.ts
new file mode 100644
index 0000000000000..8b8d4dc0e24ca
--- /dev/null
+++ b/tests/cases/compiler/nonNullableWithNullableGenericIndexedAccessArg.ts
@@ -0,0 +1,33 @@
+// @noEmit: true
+// @strict: true
+
+// repro from #50539
+
+interface StateSchema {
+  states?: {
+    [key: string]: StateSchema;
+  };
+}
+
+declare class StateNode<TStateSchema extends StateSchema> {
+  schema: TStateSchema;
+}
+
+type StateNodesConfig<TStateSchema extends StateSchema> = {
+  [K in keyof TStateSchema["states"]]: StateNode<NonNullable<TStateSchema["states"]>[K]>;
+};
+
+// repro from #50539#issuecomment-1234067835
+
+type Ordering<TOrderBy extends string> = {
+    orderBy: TOrderBy
+}
+
+type Query<TOrderBy extends string> = {
+    order?: Ordering<TOrderBy>
+}
+
+type QueryHandler<
+    TQuery extends Query<TOrderBy>,
+    TOrderBy extends string = NonNullable<TQuery["order"]>["orderBy"]
+> = {}
diff --git a/tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts b/tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts
new file mode 100644
index 0000000000000..6a6cf1007b0bb
--- /dev/null
+++ b/tests/cases/compiler/undefinedAsDiscriminantWithUnknown.ts
@@ -0,0 +1,16 @@
+// @strictNullChecks: true,false
+
+type S = 
+| { type: 'string', value: string } 
+| { type: 'number', value: number } 
+| { type: 'unknown', value: unknown }
+| { value: undefined };
+
+declare var s: S
+
+if (s.value !== undefined) {
+  s;
+}
+else {
+  s;
+}
\ No newline at end of file
diff --git a/tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts b/tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts
index 3e67f3247da3d..50c2c4fdf147e 100644
--- a/tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts
+++ b/tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts
@@ -211,3 +211,11 @@ function update<T extends Control, K extends keyof T>(control : T | undefined, k
         control[key] = value;
     }
 }
+
+// Repro from #50465
+
+type Column<T> = (keyof T extends never ? { id?: number | string } : { id: T }) & { title?: string; }
+
+function getColumnProperty<T>(column: Column<T>, key: keyof Column<T>) {
+  return column[key];
+}