fix assert_type with metaclasses #3228

[asukaminato0721]

Summary

Fixes #3228

assert_type no longer accepts a class object as exactly equal to its non-type metaclass.

Test Plan

add test

[github-actions]

According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅

[Copilot]

Pull request overview

Fixes typing.assert_type behavior for classes with custom metaclasses so that asserting a class object against its metaclass (e.g., assert_type(A, Meta)) correctly fails, aligning with the typing spec and other type checkers.

Changes:

• Updated call_assert_type to explicitly treat “class object is an instance of a non-type metaclass” as a mismatch for assert_type equivalence.
• Added a regression test covering assert_type with a custom metaclass.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
pyrefly/lib/test/simple.rs	Adds a regression testcase ensuring assert_type(A, Meta) produces an error for metaclass instances.
pyrefly/lib/alt/special_calls.rs	Adjusts assert_type checking logic to reject metaclass-instance matches (except for builtin type) even if prior equivalence logic allowed them.

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[meta-codesync]

@kinto0 has imported this pull request. If you are a Meta employee, you can view this in D103049155.