new lint: match_like_matches_macro

[robojumper]

Suggests using the matches! macro from std where appropriate.

redundant_pattern_matching has been moved into the matches pass to allow suppressing the suggestion where is_some and friends are a better replacement.

changelog: new lint: match_like_matches_macro

[rust-highfive]

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[bors]

☔ The latest upstream changes (presumably #5301) made this pull request unmergeable. Please resolve the merge conflicts.

[camsteffen]

Should this also include cases like the following?

match o {
    Some(1) => 'y',
    _ => 'n',
}

to

if matches!(o, Some(1)) { 'y' } else { 'n' }

[robojumper]

@camsteffen The transformation you describe first replaces match with if let (which is a more aggressive form of the currently already pedantic-allow single_match_else lint) and then replaces the if let header with if matches!.

I think that transformation should not be part of this lint, as the matches! macro specifically shines when it allows the match arms / block bodies (only containing only true and false) to be omitted and replaces the entire expression. That's also why I suggested this lint be in the style group and warn by default.

[phansch]

LGTM, thanks!

@bors r+

[bors]

📌 Commit 37d75da has been approved by phansch

[bors]

⌛ Testing commit 37d75da with merge 7d611d9...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: phansch
Pushing 7d611d9 to master...