Failing Test cases For Type Narrowing #20603
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A5rocks
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Jan 17, 2026
| if type(y) is int: # E: Subclass of "str" and "int" cannot exist: would have incompatible method signatures | ||
| y # E: Statement is unreachable | ||
| if type(y) is int: | ||
| y |
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I don't quite get the change here?
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Nothing can be a subclass of an integer and a string at the same time. This error existed in previous versions of Mypy, so I think we should not change it.
Co-authored-by: A5rocks <git@helvetica.moe>
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Test cases added from #20277 (initial PR) after issue #20600 (failing test cases), caused by #20492 (type narrowing PR).
Failing cases have been marked with
-xfail