From 9df32fb0299721013df62095591c0ecd72fd9c29 Mon Sep 17 00:00:00 2001
From: Hana Joo <hanajoo@google.com>
Date: Mon, 5 May 2025 06:50:24 -0700
Subject: [PATCH] Do not assert at this location. It is possible that the
 assertion triggers but pytype is indeed looking at a ParamSpec being passed
 in.

PiperOrigin-RevId: 754917442
---
 pytype/matcher.py              |  8 ++++++--
 pytype/tests/test_paramspec.py | 19 +++++++++++++++++++
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/pytype/matcher.py b/pytype/matcher.py
index 870f4139e..34d1e93a2 100644
--- a/pytype/matcher.py
+++ b/pytype/matcher.py
@@ -1198,14 +1198,18 @@ def _match_subst_against_subst(
                 type_param_map[t],
                 old_subst.copy(t=b1.AssignToNewVariable(self._node)),
             )
-          else:
-            # If t isn't a TypeVar here it should be a ParamSpec
+          elif t in self._paramspecs:
             assert t in self._paramspecs
             new_var = self.ctx.program.NewVariable()
             new_var.PasteBindingWithNewData(
                 b2, self.ctx.convert.get_maybe_abstract_instance(b2.data)
             )
             has_error = False
+          else:
+            new_var = self.ctx.program.NewVariable()
+            # Here' it's possibly a ParamSpec but the callpath to this code
+            # somehow does not assign to the self._paramspecs list.
+            has_error = False
           # If new_subst contains a TypeVar that is mutually exclusive with t,
           # then we can ignore this error because it is legal for t to not be
           # present in new_subst.
diff --git a/pytype/tests/test_paramspec.py b/pytype/tests/test_paramspec.py
index a2f1540d8..5c9ab9a08 100644
--- a/pytype/tests/test_paramspec.py
+++ b/pytype/tests/test_paramspec.py
@@ -611,6 +611,25 @@ def f(x: int, y) -> Any: ...
       """,
       )
 
+  def test_paramspec_in_callable_as_param_not_fail(self):
+    self.Check("""
+    from typing import ParamSpec, Callable
+
+    _P = ParamSpec("_P")
+    CallbleWithParamSpec = Callable[_P, None]
+
+    class A:
+      def __init__(self, callable_1: CallbleWithParamSpec, callable_2: CallbleWithParamSpec):
+        pass
+
+    class B(A):
+      def __init__(self, callable_1: CallbleWithParamSpec, callable_2: CallbleWithParamSpec):
+        super().__init__(
+            callable_1,
+            callable_2,
+        )
+    """)
+
 
 class ContextlibTest(test_base.BaseTest):
   """Test some more complex uses of contextlib."""