Fix dict.get issue for typeshed update #18806
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According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅ |
| @@ -507,7 +507,8 @@ def visit_break_stmt(self, o: BreakStmt) -> None: | |||
| self.tracker.skip_branch() | |||
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| def visit_expression_stmt(self, o: ExpressionStmt) -> None: | |||
| if isinstance(self.type_map.get(o.expr, None), (UninhabitedType, type(None))): | |||
| typ = self.type_map.get(o.expr) | |||
| if typ is None or isinstance(get_proper_type(typ), UninhabitedType): | |||
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I.e., can there be a test that would have failed without this change but now passes? It seems like that would have to require a non-"proper" type that resolves to UninhabitedType.
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Can this be tested?
Probably not. The way I understand it, UninhabitedType is a synthetic type created by mypy itself to represent a true bottom type / never. Thus I guess it won't be part of a type alias.
The mypy plugin for get_proper_type doesn't seem to take that into account. Although I'm not sure it needs to. In these cases it's just a no-op. Easier to check it's always called on unexpanded types before isinstance checks.
Fix for issue uncovered in #18803.