Fixes crash on subclassing Annotated without args, refs python#11808 (

python#11814)
DeepSourceCorp · Jan 20, 2022 · f86759e · f86759e
1 parent f11b331
commit f86759e
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Showing 2 changed files with 10 additions and 1 deletion.
diff --git a/mypy/typeanal.py b/mypy/typeanal.py
@@ -1291,7 +1291,9 @@ def visit_unbound_type(self, t: UnboundType) -> TypeVarLikeList:
             return []
         elif node and node.fullname in ('typing_extensions.Literal', 'typing.Literal'):
             return []
-        elif node and node.fullname in ('typing_extensions.Annotated', 'typing.Annotated'):
+        elif (node
+                and node.fullname in ('typing_extensions.Annotated', 'typing.Annotated')
+                and t.args):
             # Don't query the second argument to Annotated for TypeVars
             return self.query_types([t.args[0]])
         else:

diff --git a/test-data/unit/semanal-errors.test b/test-data/unit/semanal-errors.test
@@ -1435,3 +1435,10 @@ TP = ParamSpec('?')  # E: String argument 1 "?" to ParamSpec(...) does not match
 TP2: int = ParamSpec('TP2')  # E: Cannot declare the type of a parameter specification
 
 [out]
+
+
+[case testBaseClassAnnotatedWithoutArgs]
+# https://github.com/python/mypy/issues/11808
+from typing_extensions import Annotated
+# Nest line should not crash:
+class A(Annotated): pass  # E: Annotated[...] must have exactly one type argument and at least one annotation