Fixed bug that causes a false positive MRO error when creating a subc…

…lass of a generic TypedDict and another TypedDict. This addresses microsoft#6318.
StellaHuang95 · Nov 3, 2023 · 71a9b2c · 71a9b2c
1 parent fb67700
commit 71a9b2c
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Showing 2 changed files with 15 additions and 3 deletions.
diff --git a/packages/pyright-internal/src/analyzer/typeUtils.ts b/packages/pyright-internal/src/analyzer/typeUtils.ts
@@ -3006,9 +3006,9 @@ export function computeMroLinearization(classType: ClassType): boolean {
             // Generic has some special-case logic (see description of __mro_entries__
             // in PEP 560) that we need to account for here.
             if (ClassType.isBuiltIn(baseClass, 'Generic')) {
-                // If the class is a Protocol, the generic is ignored for the purposes
-                // of computing the MRO.
-                if (ClassType.isProtocolClass(classType)) {
+                // If the class is a Protocol or TypedDict, the generic is ignored for
+                // the purposes of computing the MRO.
+                if (ClassType.isProtocolClass(classType) || ClassType.isTypedDictClass(classType)) {
                     return false;
                 }
 

diff --git a/packages/pyright-internal/src/tests/samples/typedDict18.py b/packages/pyright-internal/src/tests/samples/typedDict18.py
@@ -126,3 +126,15 @@ def __init__(self, **attrs: Unpack[TD9[_T1]]) -> None:
 
 f7 = ClassA(x=1)
 reveal_type(f7, expected_text="ClassA[int]")
+
+
+class TD10(TypedDict, Generic[_T1]):
+    x: _T1
+
+
+class TD11(TypedDict):
+    y: int
+
+
+class TD12(TD10[str], TD11):
+    ...