fix reportInvalidCast false positive when casting to/from type

DetachHead · Aug 15, 2024 · 7b616d6 · 7b616d6
1 parent 270804c
commit 7b616d6
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Showing 2 changed files with 17 additions and 10 deletions.
diff --git a/packages/pyright-internal/src/analyzer/typeEvaluator.ts b/packages/pyright-internal/src/analyzer/typeEvaluator.ts
@@ -10338,7 +10338,10 @@ export function createTypeEvaluator(
             return false;
         }
 
-        if (isInstantiableClass(leftType) || (isClassInstance(leftType) && ClassType.isBuiltIn(leftType, 'type'))) {
+        if (
+            checkEq &&
+            (isInstantiableClass(leftType) || (isClassInstance(leftType) && ClassType.isBuiltIn(leftType, 'type')))
+        ) {
             if (
                 isInstantiableClass(rightType) ||
                 (isClassInstance(rightType) && ClassType.isBuiltIn(rightType, 'type'))
@@ -10350,13 +10353,11 @@ export function createTypeEvaluator(
                     return true;
                 }
             }
-            if (checkEq) {
-                // Does the class have an operator overload for eq?
-                const metaclass = leftType.shared.effectiveMetaclass;
-                if (metaclass && isClass(metaclass)) {
-                    if (lookUpClassMember(metaclass, '__eq__', MemberAccessFlags.SkipObjectBaseClass)) {
-                        return true;
-                    }
+            // Does the class have an operator overload for eq?
+            const metaclass = leftType.shared.effectiveMetaclass;
+            if (metaclass && isClass(metaclass)) {
+                if (lookUpClassMember(metaclass, '__eq__', MemberAccessFlags.SkipObjectBaseClass)) {
+                    return true;
                 }
             }
 

diff --git a/packages/pyright-internal/src/tests/samples/cast.py b/packages/pyright-internal/src/tests/samples/cast.py
@@ -1,7 +1,7 @@
-from typing import cast, Never
+from typing import Any, cast, Never
 from collections.abc import Mapping
 
-def foo(str_: str, int_or_str: int | str, dict_int_or_none: dict[str, int | None], mapping: Mapping[str, int | None]):
+def foo(str_: str, int_or_str: int | str, dict_int_or_none: dict[str, int | None], mapping: Mapping[str, int | None], type_int: type[int], type_any: type[Any], type_object: type[object]):
     cast(int, str_) # error, non-overlapping types
     cast(int | bytes, str_) # error, non-overlapping types
     cast(object, str_) # wider, no error
@@ -13,3 +13,9 @@ def foo(str_: str, int_or_str: int | str, dict_int_or_none: dict[str, int | None
     cast(Mapping[str, int], dict_int_or_none) # wider (ignore type parameters), no error
     cast(dict[str, int], mapping) # wider, no error
     cast(dict[str, bytes], mapping) # xfail, https://github.com/DetachHead/basedpyright/issues/259
+    cast(type[Any], object()) # narrower, no error
+    cast(type[object], object()) # narrower, no error
+    cast(type[int], object()) # narrower, no error
+    cast(object, type_any) # wider, no error
+    cast(object, type_object) # wider, no error
+    cast(object, type_int) # wider, no error