Detect existing turbofish on method calls to suppress useless suggestion#153751
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Some changes occurred in need_type_info.rs cc @lcnr |
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eggyal
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r=me after CI @bors delegate+ |
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✌️ @arferreira, you can now approve this pull request! If @lcnr told you to " |
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| --> $DIR/useless-turbofish-suggestion.rs:19:7 | ||
| | | ||
| LL | S.f::<u32, _>(42); | ||
| | ^ cannot infer type of the type parameter `B` declared on the method `f` |
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…stion, r=lcnr Detect existing turbofish on method calls to suppress useless suggestion `expr_inferred_arg_iter` hardcoded `have_turbofish: false` for `MethodCall` expressions, while the `Path` case properly checked for existing type arguments via `segment.args`. This meant the "consider specifying the generic arguments" suggestion always fired on method calls, even when the user already had a turbofish, producing a suggestion that just rewrote user syntax into fully qualified form without resolving anything. Fixes rust-lang#153732. cc @eggyal
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…uwer Rollup of 5 pull requests Successful merges: - #153751 (Detect existing turbofish on method calls to suppress useless suggestion) - #153780 (Remove `MTLock`) - #151194 (Fix wrong suggestion for returning async closure) - #151572 (Fix Hexagon ABI calling convention for small aggregates) - #153725 (Fix that `./x test --no-doc` actually keeps the same behaviour for backwards compatability)
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…uwer Rollup of 5 pull requests Successful merges: - #153705 (Always generate generics in delegation that match trait in trait impl scenario) - #153751 (Detect existing turbofish on method calls to suppress useless suggestion) - #153780 (Remove `MTLock`) - #151572 (Fix Hexagon ABI calling convention for small aggregates) - #153725 (Fix that `./x test --no-doc` actually keeps the same behaviour for backwards compatability)
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…uwer Rollup of 5 pull requests Successful merges: - rust-lang/rust#153705 (Always generate generics in delegation that match trait in trait impl scenario) - rust-lang/rust#153751 (Detect existing turbofish on method calls to suppress useless suggestion) - rust-lang/rust#153780 (Remove `MTLock`) - rust-lang/rust#151572 (Fix Hexagon ABI calling convention for small aggregates) - rust-lang/rust#153725 (Fix that `./x test --no-doc` actually keeps the same behaviour for backwards compatability)
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…ent, r=Kivooeo,eggyal Point turbofish inference errors at the uninferred generic arg Follow-up to rust-lang#153751. When a method call has a turbofish with an uninferred generic argument, point the diagnostic span at the specific `_` that couldn't be inferred instead of the method name. Before: ```rust LL | S.f::<u32, _>(42); | ^ cannot infer type of the type parameter `B` ``` After: ```rust LL | S.f::<u32, _>(42); | ^ cannot infer type of the type parameter `B` ``` Path expressions (`None::<_>`, `foo::<_>()`) are not handled yet, that's a separate code path. cc @eggyal
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expr_inferred_arg_iterhardcodedhave_turbofish: falseforMethodCallexpressions, while thePathcase properly checked for existing type arguments viasegment.args. This meant the "consider specifying the generic arguments" suggestion always fired on method calls, even when the user already had a turbofish, producing a suggestion that just rewrote user syntax into fully qualified form without resolving anything.Fixes #153732.
cc @eggyal