Do not propose to elide lifetimes if this causes an ambiguity #13929
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| type Result = ControlFlow<bool>; | ||
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| fn visit_lifetime(&mut self, lifetime: &Lifetime) -> Self::Result { | ||
| ControlFlow::Break(lifetime.is_elided() || lifetime.is_anonymous()) |
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This currently breaks on the first lifetime it finds. Meaning that (x: Cx<'_, 'tcx>) would say it's anonymous, right?
It feels like this should only break if it finds a user-defined lifetime 🤔
Could you also add a test for this?
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Yes, but:
- when checking the output type, we don't care about the lifetime being anonymous (we just want to know if we have at least one lifetime)
- we check the input types only when the function supports lifetime elision, which is not the case here because we have at least two input lifetimes (
'_and'tcx)
Does that make sense? I've added a test, let me know if this is what you had in mind.
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It make sense, I didn't know that two LTs implied that they can't be elapsed
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Some lifetimes in function return types are not bound to concrete content and can be set arbitrarily. Clippy should not propose to replace them by the default `'_` lifetime if such a lifetime cannot be determined unambigously.
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Silly me. @xFrednet changelog added. |
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Some lifetimes in function return types are not bound to concrete content and can be set arbitrarily. Clippy should not propose to replace them by the default
'_lifetime if such a lifetime cannot be determined unambigously.I added a field to the
LifetimeCheckerandUsageto flag lifetimes that cannot be replaced by default ones, but it feels a bit hacky.Fix #13923
changelog: [
needless_lifetimes]: remove false positives by checking that lifetimes can indeed be elided