Fixed a bug that resulted in a false positive error when constructing…

… a tuple of classes in the second argument of an `isinstance` or `issubclass` call. This addresses #5018.
microsoft · Apr 27, 2023 · 924bf71 · 924bf71
1 parent 2575969
commit 924bf71
Show file tree

Hide file tree

Showing 2 changed files with 6 additions and 1 deletion.
diff --git a/packages/pyright-internal/src/analyzer/checker.ts b/packages/pyright-internal/src/analyzer/checker.ts
@@ -3594,6 +3594,7 @@ export class Checker extends ParseTreeWalker {
 
         doForEachSubtype(type, (subtype) => {
             subtype = this._evaluator.makeTopLevelTypeVarsConcrete(subtype);
+            subtype = transformPossibleRecursiveTypeAlias(subtype);
 
             switch (subtype.category) {
                 case TypeCategory.Any:

diff --git a/packages/pyright-internal/src/tests/samples/isinstance3.py b/packages/pyright-internal/src/tests/samples/isinstance3.py
@@ -4,7 +4,7 @@
 
 
 from abc import abstractmethod
-from typing import Any, Generic, Tuple, Type, TypeVar, Union
+from typing import Any, Generic, Sequence, Tuple, Type, TypeVar, Union
 
 
 _T = TypeVar("_T", int, str)
@@ -57,3 +57,7 @@ def execute(self, var: Union[_T, Tuple[_T]]) -> None:
 
         if isinstance(var, self.v2):
             pass
+
+
+def func1(exceptions: Sequence[type[BaseException]], exception: Exception):
+    return isinstance(exception, tuple(exceptions))