Carl Meyer e12747a903 [ty] simplify return type of place_from_declarations (#19884) ... ## Summary A [passing comment](https://github.com/astral-sh/ruff/pull/19711#issuecomment-3169312014) led me to explore why we didn't report a class attribute as possibly unbound if it was a method and defined in two different conditional branches. I found that the reason was because of our handling of "conflicting declarations" in `place_from_declarations`. It returned a `Result` which would be `Err` in case of conflicting declarations. But we only actually care about conflicting declarations when we are actually doing type inference on that scope and might emit a diagnostic about it. And in all cases (including that one), we want to otherwise proceed with the union of the declared types, as if there was no conflict. In several cases we were failing to handle the union of declared types in the same way as a normal declared type if there was a declared-types conflict. The `Result` return type made this mistake really easy to make, as we'd match on e.g. `Ok(Place::Type(...))` and do one thing, then match on `Err(...)` and do another, even though really both of those cases should be handled the same. This PR refactors `place_from_declarations` to instead return a struct which always represents the declared type we should use in the same way, as well as carrying the conflicting declared types, if any. This struct has a method to allow us to explicitly ignore the declared-types conflict (which is what we want in most cases), as well as a method to get the declared type and the conflict information, in the case where we want to emit a diagnostic on the conflict. ## Test Plan Existing CI; added a test showing that we now understand a multiply-conditionally-defined method as possibly-unbound. This does trigger issues on a couple new fuzzer seeds, but the issues are just new instances of an already-known (and rarely occurring) problem which I already plan to address in a future PR, so I think it's OK to land as-is. I happened to build this initially on top of https://github.com/astral-sh/ruff/pull/19711, which adds invalid-await diagnostics, so I also updated some invalid-syntax tests to not await on an invalid type, since the purpose of those tests is to check the syntactic location of the `await`, not the validity of the awaited type.		2025-08-13 14:17:08 +00:00
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py-fuzzer	[ty] simplify return type of place_from_declarations (#19884)	2025-08-13 14:17:08 +00:00
ruff
ruff-ecosystem