Fixed regression with LiteralString. It is compatible with str even in cases where invariance is in effect.

msfterictraut · msfterictraut · commit e33c1230c0c7 · 2022-08-07T18:24:10.000-07:00
diff --git a/packages/pyright-internal/src/analyzer/typeEvaluator.ts b/packages/pyright-internal/src/analyzer/typeEvaluator.ts
@@ -20982,7 +20982,7 @@ export function createTypeEvaluator(importLookup: ImportLookup, evaluatorOptions
                 }
             }
 
-            const concreteSrcType = makeTopLevelTypeVarsConcrete(srcType);
+            let concreteSrcType = makeTopLevelTypeVarsConcrete(srcType);
             if (isClass(concreteSrcType) && TypeBase.isInstance(concreteSrcType)) {
                 if (destType.literalValue !== undefined) {
                     const srcLiteral = concreteSrcType.literalValue;
@@ -21002,7 +21002,15 @@ export function createTypeEvaluator(importLookup: ImportLookup, evaluatorOptions
                 if (ClassType.isBuiltIn(destType, 'LiteralString')) {
                     if (ClassType.isBuiltIn(concreteSrcType, 'str') && concreteSrcType.literalValue !== undefined) {
                         return true;
+                    } else if (ClassType.isBuiltIn(concreteSrcType, 'LiteralString')) {
+                        return true;
                     }
+                } else if (
+                    ClassType.isBuiltIn(concreteSrcType, 'LiteralString') &&
+                    strClassType &&
+                    isInstantiableClass(strClassType)
+                ) {
+                    concreteSrcType = ClassType.cloneAsInstance(strClassType);
                 }
 
                 if (
diff --git a/packages/pyright-internal/src/tests/samples/literalString1.py b/packages/pyright-internal/src/tests/samples/literalString1.py
@@ -71,3 +71,5 @@ def func6(a: LiteralString):
     v2 = a[0]
 
     a = "hi"
+
+    v3: list[str] = "1 2 3".split(" ")

Original file line number	Diff line number	Diff line change
`@@ -20982,7 +20982,7 @@ export function createTypeEvaluator(importLookup: ImportLookup, evaluatorOptions`
`20982`	`20982`	`}`
`20983`	`20983`	`}`
`20984`	`20984`
`20985`		`- const concreteSrcType = makeTopLevelTypeVarsConcrete(srcType);`
	`20985`	`+ let concreteSrcType = makeTopLevelTypeVarsConcrete(srcType);`
`20986`	`20986`	`if (isClass(concreteSrcType) && TypeBase.isInstance(concreteSrcType)) {`
`20987`	`20987`	`if (destType.literalValue !== undefined) {`
`20988`	`20988`	`const srcLiteral = concreteSrcType.literalValue;`
`@@ -21002,7 +21002,15 @@ export function createTypeEvaluator(importLookup: ImportLookup, evaluatorOptions`
`21002`	`21002`	`if (ClassType.isBuiltIn(destType, 'LiteralString')) {`
`21003`	`21003`	`if (ClassType.isBuiltIn(concreteSrcType, 'str') && concreteSrcType.literalValue !== undefined) {`
`21004`	`21004`	`return true;`
	`21005`	`+ } else if (ClassType.isBuiltIn(concreteSrcType, 'LiteralString')) {`
	`21006`	`+ return true;`
`21005`	`21007`	`}`
	`21008`	`+ } else if (`
	`21009`	`+ ClassType.isBuiltIn(concreteSrcType, 'LiteralString') &&`
	`21010`	`+ strClassType &&`
	`21011`	`+ isInstantiableClass(strClassType)`
	`21012`	`+ ) {`
	`21013`	`+ concreteSrcType = ClassType.cloneAsInstance(strClassType);`
`21006`	`21014`	`}`
`21007`	`21015`
`21008`	`21016`	`if (`