microsoft · sandersn · Aug 15, 2018 · Aug 8, 2018 · Aug 9, 2018 · Aug 9, 2018
diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
@@ -2480,6 +2480,11 @@ namespace ts {
 
         function bindSpecialPropertyAssignment(node: BinaryExpression) {
             const lhs = node.left as PropertyAccessEntityNameExpression;
+            // Class declarations in Typescript do not allow property declarations
+            const parentSymbol = lookupSymbolForPropertyAccess(lhs.expression);
+            if (!isInJavaScriptFile(node) && !isFunctionSymbol(parentSymbol)) {
+                return;
+            }
             // Fix up parent pointers since we're going to use these nodes before we bind into them
             node.left.parent = node;
             node.right.parent = node;

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -4821,48 +4821,45 @@ namespace ts {
         }
 
         /** If we don't have an explicit JSDoc type, get the type from the initializer. */
-        function getInitializerTypeFromSpecialDeclarations(symbol: Symbol, resolvedSymbol: Symbol | undefined, expression: Expression, special: SpecialPropertyAssignmentKind) {
-            if (isBinaryExpression(expression)) {
-                const type = resolvedSymbol ? getTypeOfSymbol(resolvedSymbol) : getWidenedLiteralType(checkExpressionCached(expression.right));
-                if (type.flags & TypeFlags.Object &&
-                    special === SpecialPropertyAssignmentKind.ModuleExports &&
-                    symbol.escapedName === InternalSymbolName.ExportEquals) {
-                    const exportedType = resolveStructuredTypeMembers(type as ObjectType);
-                    const members = createSymbolTable();
-                    copyEntries(exportedType.members, members);
-                    if (resolvedSymbol && !resolvedSymbol.exports) {
-                        resolvedSymbol.exports = createSymbolTable();
-                    }
-                    (resolvedSymbol || symbol).exports!.forEach((s, name) => {
-                        if (members.has(name)) {
-                            const exportedMember = exportedType.members.get(name)!;
-                            const union = createSymbol(s.flags | exportedMember.flags, name);
-                            union.type = getUnionType([getTypeOfSymbol(s), getTypeOfSymbol(exportedMember)]);
-                            members.set(name, union);
-                        }
-                        else {
-                            members.set(name, s);
-                        }
-                    });
-                    const result = createAnonymousType(
-                        exportedType.symbol,
-                        members,
-                        exportedType.callSignatures,
-                        exportedType.constructSignatures,
-                        exportedType.stringIndexInfo,
-                        exportedType.numberIndexInfo);
-                    result.objectFlags |= (getObjectFlags(type) & ObjectFlags.JSLiteral); // Propagate JSLiteral flag
-                    return result;
+        function getInitializerTypeFromSpecialDeclarations(symbol: Symbol, resolvedSymbol: Symbol | undefined, expression: BinaryExpression, special: SpecialPropertyAssignmentKind) {
+            const type = resolvedSymbol ? getTypeOfSymbol(resolvedSymbol) : getWidenedLiteralType(checkExpressionCached(expression.right));
+            if (type.flags & TypeFlags.Object &&
+                special === SpecialPropertyAssignmentKind.ModuleExports &&
+                symbol.escapedName === InternalSymbolName.ExportEquals) {
+                const exportedType = resolveStructuredTypeMembers(type as ObjectType);
+                const members = createSymbolTable();
+                copyEntries(exportedType.members, members);
+                if (resolvedSymbol && !resolvedSymbol.exports) {
+                    resolvedSymbol.exports = createSymbolTable();
                 }
-                if (isEmptyArrayLiteralType(type)) {
-                    if (noImplicitAny) {
-                        reportImplicitAnyError(expression, anyArrayType);
+                (resolvedSymbol || symbol).exports!.forEach((s, name) => {
+                    if (members.has(name)) {
+                        const exportedMember = exportedType.members.get(name)!;
+                        const union = createSymbol(s.flags | exportedMember.flags,
8000
 name);
+                        union.type = getUnionType([getTypeOfSymbol(s), getTypeOfSymbol(exportedMember)]);
+                        members.set(name, union);
                     }
-                    return anyArrayType;
+                    else {
+                        members.set(name, s);
+                    }
+                });
+                const result = createAnonymousType(
+                    exportedType.symbol,
+                    members,
+                    exportedType.callSignatures,
+                    exportedType.constructSignatures,
+                    exportedType.stringIndexInfo,
+                    exportedType.numberIndexInfo);
+                result.objectFlags |= (getObjectFlags(type) & ObjectFlags.JSLiteral); // Propagate JSLiteral flag
+                return result;
+            }
+            if (isEmptyArrayLiteralType(type)) {
+                if (noImplicitAny) {
+                    reportImplicitAnyError(expression, anyArrayType);
                 }
-                return type;
+                return anyArrayType;
             }
-            return neverType;
+            return type;
         }
 
         function isDeclarationInConstructor(expression: Expression) {
@@ -5085,7 +5082,9 @@ namespace ts {
                 if (symbol.flags & (SymbolFlags.Function | SymbolFlags.Method | SymbolFlags.Class | SymbolFlags.Enum | SymbolFlags.ValueModule)) {
                     return getTypeOfFuncClassEnumModule(symbol);
                 }
-                type = tryGetTypeFromEffectiveTypeNode(declaration) || anyType;
+                type = isBinaryExpression(declaration.parent) ?
+                    getWidenedTypeFromJSPropertyAssignments(symbol) :
+                    tryGetTypeFromEffectiveTypeNode(declaration) || anyType;
             }
             else if (isPropertyAssignment(declaration)) {
                 type = tryGetTypeFromEffectiveTypeNode(declaration) || checkPropertyAssignment(declaration);
@@ -16025,7 +16024,24 @@ namespace ts {
                 case SpecialPropertyAssignmentKind.PrototypeProperty:
                     // If `binaryExpression.left` was assigned a symbol, then this is a new declaration; otherwise it is an assignment to an existing declaration.
                     // See `bindStaticPropertyAssignment` in `binder.ts`.
-                    return !binaryExpression.left.symbol || binaryExpression.left.symbol.valueDeclaration && !!getJSDocTypeTag(binaryExpression.left.symbol.valueDeclaration);
+                    if (!binaryExpression.left.symbol) {
+                        return true;
+                    }
+                    else {
+                        const decl = binaryExpression.left.symbol.valueDeclaration;
+                        if (!decl) {
+                            return false;
+                        }
+                        if (isInJavaScriptFile(decl)) {
+                            return !!getJSDocTypeTag(decl);
+                        }
+                        else if (isIdentifier((binaryExpression.left as PropertyAccessExpression).expression)) {
+                            const id = (binaryExpression.left as PropertyAccessExpression).expression as Identifier;
+                            const parentSymbol = resolveName(id, id.escapedText, SymbolFlags.Value, undefined, id.escapedText, /*isUse*/ true);
+                            return !isFunctionSymbol(parentSymbol);
+                        }
+                        return true;
+                    }
                 case SpecialPropertyAssignmentKind.ThisProperty:
                 case SpecialPropertyAssignmentKind.ModuleExports:
                     return !binaryExpression.symbol || binaryExpression.symbol.valueDeclaration && !!getJSDocTypeTag(binaryExpression.symbol.valueDeclaration);

diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
@@ -1725,12 +1725,15 @@ namespace ts {
     }
 
     export function getDeclarationOfJSInitializer(node: Node): Node | undefined {
-        if (!isInJavaScriptFile(node) || !node.parent) {
+        if (!node.parent) {
             return undefined;
         }
         let name: Expression | BindingName | undefined;
         let decl: Node | undefined;
         if (isVariableDeclaration(node.parent) && node.parent.initializer === node) {
+            if (!isInJavaScriptFile(node) && !isVarConst(node.parent)) {
+                return undefined;
+            }
             name = node.parent.name;
             decl = node.parent;
         }
@@ -1892,8 +1895,12 @@ namespace ts {
     /// Given a BinaryExpression, returns SpecialPropertyAssignmentKind for the various kinds of property
     /// assignments we treat as special in the binder
     export function getSpecialPropertyAssignmentKind(expr: BinaryExpression): SpecialPropertyAssignmentKind {
-        if (!isInJavaScriptFile(expr) ||
-            expr.operatorToken.kind !== SyntaxKind.EqualsToken ||
+        const special = getSpecialPropertyAssignmentKindWorker(expr);
+        return special === SpecialPropertyAssignmentKind.Property || isInJavaScriptFile(expr) ? special : SpecialPropertyAssignmentKind.None;
+    }
+
+    function getSpecialPropertyAssignmentKindWorker(expr: BinaryExpression): SpecialPropertyAssignmentKind {
+        if (expr.operatorToken.kind !== SyntaxKind.EqualsToken ||
             !isPropertyAccessExpression(expr.left)) {
             return SpecialPropertyAssignmentKind.None;
         }
@@ -1954,6 +1961,14 @@ namespace ts {
             !!getJSDocTypeTag(expr.parent);
     }
 
+    export function isFunctionSymbol(symbol: Symbol | undefined) {
+        if (!symbol || !symbol.valueDeclaration) {
+            return false;
+        }
+        const decl = symbol.valueDeclaration;
+        return decl.kind === SyntaxKind.FunctionDeclaration || isVariableDeclaration(decl) && decl.initializer && isFunctionLike(decl.initializer);
+    }
+
     export function importFromModuleSpecifier(node: StringLiteralLike): AnyValidImportOrReExport {
         return tryGetImportFromModuleSpecifier(node) || Debug.fail(Debug.showSyntaxKind(node.parent));
     }
@@ -2354,7 +2369,10 @@ namespace ts {
                 }
                 else {
                     const binExp = name.parent.parent;
-                    return isBinaryExpression(binExp) && getSpecialPropertyAssignmentKind(binExp) !== SpecialPropertyAssignmentKind.None && getNameOfDeclaration(binExp) === name;
+                    return isBinaryExpression(binExp) &&
+                        getSpecialPropertyAssignmentKind(binExp) !== SpecialPropertyAssignmentKind.None &&
+                        (binExp.left.symbol || binExp.symbol) &&
+                        getNameOfDeclaration(binExp) === name;
                 }
             }
             default:

diff --git a/tests/baselines/reference/fixSignatureCaching.errors.txt b/tests/baselines/reference/fixSignatureCaching.errors.txt
@@ -24,7 +24,6 @@ tests/cases/conformance/fixSignatureCaching.ts(474,38): error TS2339: Property '
 tests/cases/conformance/fixSignatureCaching.ts(481,22): error TS2339: Property 'findMatch' does not exist on type '{}'.
 tests/cases/conformance/fixSignatureCaching.ts(481,37): error TS2339: Property 'mobileDetectRules' does not exist on type '{}'.
 tests/cases/conformance/fixSignatureCaching.ts(489,18): error TS2339: Property 'isMobileFallback' does not exist on type '{}'.
-tests/cases/conformance/fixSignatureCaching.ts(490,39): error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
 tests/cases/conformance/fixSignatureCaching.ts(492,37): error TS2339: Property 'FALLBACK_MOBILE' does not exist on type '{}'.
 tests/cases/conformance/fixSignatureCaching.ts(495,51): error TS2339: Property 'FALLBACK_PHONE' does not exist on type '{}'.
 tests/cases/conformance/fixSignatureCaching.ts(498,52): error TS2339: Property 'FALLBACK_TABLET' does not exist on type '{}'.
@@ -49,13 +48,8 @@ tests/cases/conformance/fixSignatureCaching.ts(872,25): error TS2339: Property '
 tests/cases/conformance/fixSignatureCaching.ts(893,25): error TS2339: Property 'getVersionStr' does not exist on type '{}'.
 tests/cases/conformance/fixSignatureCaching.ts(915,36): error TS2339: Property 'findMatches' does not exist on type '{}'.
 tests/cases/conformance/fixSignatureCaching.ts(915,53): error TS2339: Property 'mobileDetectRules' does not exist on type '{}'.
-tests/cases/conformance/fixSignatureCaching.ts(944,33): error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
 tests/cases/conformance/fixSignatureCaching.ts(955,42): error TS2339: Property 'mobileGrade' does not exist on type '{}'.
-tests/cases/conformance/fixSignatureCaching.ts(963,22): error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
 tests/cases/conformance/fixSignatureCaching.ts(964,57): error TS2339: Property 'getDeviceSmallerSide' does not exist on type '{}'.
-tests/cases/conformance/fixSignatureCaching.ts(967,22): error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
-tests/cases/conformance/fixSignatureCaching.ts(971,18): error TS2339: Property '_impl' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
-tests/cases/conformance/fixSignatureCaching.ts(973,18): error TS2339: Property 'version' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
 tests/cases/conformance/fixSignatureCaching.ts(978,16): error TS2304: Cannot find name 'module'.
 tests/cases/conformance/fixSignatureCaching.ts(978,42): error TS2304: Cannot find name 'module'.
 tests/cases/conformance/fixSignatureCaching.ts(979,37): error TS2304: Cannot find name 'module'.
@@ -65,7 +59,7 @@ tests/cases/conformance/fixSignatureCaching.ts(981,16): error TS2304: Cannot fin
 tests/cases/conformance/fixSignatureCaching.ts(983,44): error TS2339: Property 'MobileDetect' does not exist on type 'Window'.
 
 
-==== tests/cases/conformance/fixSignatureCaching.ts (65 errors) ====
+==== tests/cases/conformance/fixSignatureCaching.ts (59 errors) ====
     // Repro from #10697
 
     (function (define, undefined) {
@@ -608,8 +602,6 @@ tests/cases/conformance/fixSignatureCaching.ts(983,44): error TS2339: Property '
                      ~~~~~~~~~~~~~~~~
 !!! error TS2339: Property 'isMobileFallback' does not exist on type '{}'.
                 phoneSized = MobileDetect.isPhoneSized(maxPhoneWidth);
-                                          ~~~~~~~~~~~~
-!!! error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
                 if (phoneSized === undefined) {
                     cache.mobile = impl.FALLBACK_MOBILE;
                                         ~~~~~~~~~~~~~~~
@@ -1112,8 +1104,6 @@ tests/cases/conformance/fixSignatureCaching.ts(983,44): error TS2339: Property '
              */
             isPhoneSized: function (maxPhoneWidth) {
                 return MobileDetect.isPhoneSized(maxPhoneWidth || this.maxPhoneWidth);
-                                    ~~~~~~~~~~~~
-!!! error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
             },
 
             /**
@@ -1135,26 +1125,18 @@ tests/cases/conformance/fixSignatureCaching.ts(983,44): error TS2339: Property '
         // environment-dependent
         if (typeof window !== 'undefined' && window.screen) {
             MobileDetect.isPhoneSized = function (maxPhoneWidth) {
-                         ~~~~~~~~~~~~
-!!! error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
                 return maxPhoneWidth < 0 ? undefined : impl.getDeviceSmallerSide() <= maxPhoneWidth;
                                                             ~~~~~~~~~~~~~~~~~~~~
 !!! error TS2339: Property 'getDeviceSmallerSide' does not exist on type '{}'.
             };
         } else {
             MobileDetect.isPhoneSized = function () {};
-                         ~~~~~~~~~~~~
-!!! error TS2339: Property 'isPhoneSized' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
         }
 
         // should not be replaced by a completely new object - just overwrite existing methods
         MobileDetect._impl = impl;
-                     ~~~~~
-!!! error TS2339: Property '_impl' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
 
         MobileDetect.version = '1.3.3 2016-07-31';
-                     ~~~~~~~
-!!! error TS2339: Property 'version' does not exist on type '(userAgent: any, maxPhoneWidth: any) => void'.
 
         return MobileDetect;
     }); // end of call of define()
@@ -1183,4 +1165,5 @@ tests/cases/conformance/fixSignatureCaching.ts(983,44): error TS2339: Property '
             // please file a bug if you get this error!
             throw new Error('unknown environment');
         }
-    })());
+    })());
+
diff --git a/tests/baselines/reference/fixSignatureCaching.js b/tests/baselines/reference/fixSignatureCaching.js
@@ -986,7 +986,8 @@ define(function () {
         // please file a bug if you get this error!
         throw new Error('unknown environment');
     }
-})());
+})());
+
 
 //// [fixSignatureCaching.js]
 // Repro from #10697