Avoid crashing in case where a TypeVar is trying to be matched with a ParamSpecMatch. It seems there's currently no machinery to match it, so we just avoid it from crashing, by considering them to match.

PiperOrigin-RevId: 774822686

Author: h-joo

pytype/matcher.py

@@ -757,6 +757,11 @@ def _check_type_param_consistency(
             for old_value in old_concrete_values:
               if self._satisfies_common_superclass([new_value, old_value]):
                 has_error = False
+              elif isinstance(old_value, function.ParamSpecMatch):
+                # TODO - Technically we need to check the type parameter against
+                # ParamSpec to check case the restrictions are different, but it
+                # seems we don't have the machinery to check that yet in pytype.
+                has_error = False
               elif old_value.cls.is_protocol:
                 with self._track_partially_matched_protocols():
                   protocol_subst = datatypes.AliasingDict(subst)

pytype/tests/test_typevar2.py

@@ -1217,6 +1217,23 @@ def f(self, x: T) -> T:
             return x
       """)
 
+  def test_check_type_param_against_param_spec(self):
+    self.Check("""
+      import multiprocessing.pool
+      from typing import Callable, ParamSpec, TypeVar, Any
+      _T = TypeVar('_T')
+      _Args = ParamSpec('_Args')
+
+      def decorator() -> Callable[[Callable[_Args, _T]], Callable[_Args, _T]]:
+        pass # pytype: disable=bad-return-type
+      def foo():
+        @decorator()
+        def f(i: int):
+          return i
+        with multiprocessing.pool.ThreadPool(10) as pool:
+          a: list[Any] = pool.map(f, list(range(10))) # TODO: Should be list[int]
+    """)
+
 
 if __name__ == "__main__":
   test_base.main()