From 2bb984436895436c9b9291de0304e34ec14afec2 Mon Sep 17 00:00:00 2001
From: Maggie Moss <maggiemoss@meta.com>
Date: Mon, 23 Mar 2026 12:05:34 -0700
Subject: [PATCH] Fix StrictMock stub to use class inheriting from Any instead
 of alias
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Summary:
The StrictMock type stubs across strictmock and testslide defined `StrictMock = Any`, making it a type alias for `Any`. Pyrefly treats bare `Any` as non-instantiable, causing ~14,700 `bad-instantiation` errors (`Any cannot be instantiated`) across ~3,500 test files in fbcode.

Additionally, when the stub was changed to a plain `class StrictMock`, Pyrefly correctly flagged ~13,500 `bad-argument-type` errors where `StrictMock` instances were passed to functions expecting specific types — which is the intended usage of StrictMock as a mock stand-in.

The fix changes all four stub files from:
```
StrictMock = Any
```
to:
```
class StrictMock(Any): ...
```

This makes StrictMock an instantiable class that inherits from Any, so it is both constructible and assignable to any type — matching its real-world usage as a universal mock object.

Affected stubs:
- fbcode/strictmock/strict_mock.pyi
- fbcode/testslide/testslide/strict_mock.pyi
- fbcode/python/typeshed_internal/testslide/core/strict_mock.pyi
- fbcode/python/typeshed_experimental/testslide/core/strict_mock.pyi

Differential Revision: D97783042
---
 testslide/strict_mock.pyi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/testslide/strict_mock.pyi b/testslide/strict_mock.pyi
index 625d3e1..583237a 100644
--- a/testslide/strict_mock.pyi
+++ b/testslide/strict_mock.pyi
@@ -1,4 +1,4 @@
 # pyre-unsafe
 from typing import Any
 
-StrictMock = Any
+class StrictMock(Any): ...