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Merged
merged 2 commits into from
Dec 2, 2024
Merged

Add more cases to the useless_conversion lint #13756

merged 2 commits into from
Dec 2, 2024
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@samueltardieu samueltardieu commented Nov 29, 2024 •
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The new cases are the application of Into::into or From::from through the following functions with no effect:

  • Option::map()
  • Result::map() and Result::map_err()
  • ControlFlow::map_break() and ControlFlow::map_err()
  • Iterator::map()

changelog: [useless_conversion]: detect useless calls to Into::into and From::from application through map* methods

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rustbot commented Nov 29, 2024

r? @blyxyas

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@rustbot rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties label Nov 29, 2024
@samueltardieu samueltardieu mentioned this pull request Nov 29, 2024
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The hits in lintcheck are true positives.

@samueltardieu samueltardieu force-pushed the push-qryupxlomuwt branch 3 times, most recently from 159742f to eac1e50 Compare November 30, 2024 19:11
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Lookup code will be simplified when rust-lang/rust#133686 is merged and synchronized with Clippy.

@samueltardieu
Add more cases to the useless_conversion lint
9a692ec 
The new cases are `x.map(f)` and `x.map_err(f)` when `f` is `Into::into`
or `From::from` with the same input and output types.
@samueltardieu samueltardieu force-pushed the push-qryupxlomuwt branch 2 times, most recently from 723b9a6 to 856aa03 Compare November 30, 2024 21:00
blyxyas
blyxyas reviewed Dec 1, 2024
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clippy_lints/src/useless_conversion.rs Outdated
return true;
}

// Necessary for `core::ops::control_flow::ControlFlow` until a diagnostic item
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Could you add FIXME: Add ControlFlow diagnostic item, so that in the future we can add necessary diagnostic items in masse.

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Will do. My PR has been merged into rust-lang so we should get it at the next sync.

clippy_lints/src/useless_conversion.rs
return true;
}
}
if is_trait_method(cx, expr, sym::Iterator) {
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Do we really want to lint for any methods of Iterator? What would the use case for this branch?

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This only activates for the recognized methods (map_*), no other methods of Iterator will trigger that.

blyxyas
blyxyas approved these changes Dec 2, 2024
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LGTM, thanks! ❤️
Could you squash that third commit into the second one?

@samueltardieu
Add more receivers to useless_conversion
ab5d55c 
- `ControlFlow::map_break()`
- `ControlFlow::map_continue()`
- `Iterator::map()`
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Could you squash that third commit into the second one?

Done

@blyxyas blyxyas added this pull request to the merge queue Dec 2, 2024
Merged via the queue into rust-lang:master with commit 2ddfc92 Dec 2, 2024
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@samueltardieu samueltardieu deleted the push-qryupxlomuwt branch December 30, 2024 23:49
gsson pushed a commit to gsson/scylla-rust-driver that referenced this pull request Feb 22, 2025
Fix clippy::useless_conversion lint in Session changed in clippy 0.1.85
279f4ad 
Introduced by
rust-lang/rust-clippy#13756
gsson pushed a commit to gsson/scylla-rust-driver that referenced this pull request Feb 22, 2025
Fix clippy::useless_conversion lint in Session changed in clippy 0.1.85
de6a337 
Introduced by
rust-lang/rust-clippy#13756
@gsson gsson mentioned this pull request Feb 22, 2025
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