never patterns: suggest ! patterns on non-exhaustive matches
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| @@ -1020,6 +1020,14 @@ fn report_non_exhaustive_match<'p, 'tcx>( | |||
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| let mut suggestion = None; | |||
| let sm = cx.tcx.sess.source_map(); | |||
| let suggested_arm = if witnesses.len() < 4 | |||
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Because that's also the limit used above to choose whether to report patterns or _. You're right this should be made clear, let me clean this
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I just find it strange that this applies to only the never branch, since the other half of the if could suffer from the same problem?
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There were actually three places using this magic threshold ^^' Fixed in the last commit
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If there are more than 4 witnesses we suggest _ => todo!(), it doesn't make sense to remove the todo!() then. And I can't just suggest ! either because the type might not be empty.
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@bors r+ |
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…ler-errors never patterns: suggest `!` patterns on non-exhaustive matches When a match is non-exhaustive we now suggest never patterns whenever it makes sense. r? `@compiler-errors`
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…iaskrgr Rollup of 12 pull requests Successful merges: - rust-lang#121258 (Reject overly generic assoc const binding types) - rust-lang#121823 (never patterns: suggest `!` patterns on non-exhaustive matches) - rust-lang#122060 (Stabilize `imported_main`) - rust-lang#122158 (Provide structured suggestion for `#![feature(foo)]`) - rust-lang#122642 (Improve wording of `Vec::swap_remove`) - rust-lang#122675 (core: document default attribute stabilization) - rust-lang#122687 (`NormalizesTo`: return nested goals to caller) - rust-lang#122691 (Fix ICE: `global_asm!()` Don't Panic When Unable to Evaluate Constant) - rust-lang#122693 (Fix heading anchors in doc pages.) - rust-lang#122699 (Fix a typo in the 1.77.0 relnotes) - rust-lang#122700 (Remove redundant files, rename base riscv32 file) - rust-lang#122701 (Detect allocator for box in `must_not_suspend` lint) r? `@ghost` `@rustbot` modify labels: rollup
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…iaskrgr Rollup of 11 pull requests Successful merges: - rust-lang#121258 (Reject overly generic assoc const binding types) - rust-lang#121823 (never patterns: suggest `!` patterns on non-exhaustive matches) - rust-lang#122060 (Stabilize `imported_main`) - rust-lang#122158 (Provide structured suggestion for `#![feature(foo)]`) - rust-lang#122642 (Improve wording of `Vec::swap_remove`) - rust-lang#122675 (core: document default attribute stabilization) - rust-lang#122687 (`NormalizesTo`: return nested goals to caller) - rust-lang#122693 (Fix heading anchors in doc pages.) - rust-lang#122699 (Fix a typo in the 1.77.0 relnotes) - rust-lang#122700 (Remove redundant files, rename base riscv32 file) - rust-lang#122701 (Detect allocator for box in `must_not_suspend` lint) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#121823 - Nadrieril:never-witnesses, r=compiler-errors never patterns: suggest `!` patterns on non-exhaustive matches When a match is non-exhaustive we now suggest never patterns whenever it makes sense. r? ``@compiler-errors``
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This caused a small regression. I'm surprised because a far as I can tell this only touches error paths (except when |
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When a match is non-exhaustive we now suggest never patterns whenever it makes sense.
r? @compiler-errors