fix: make compare_lines a valid total order (#105)#106
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The previous comparator could return Ordering::Less for both compare_lines(a, b) and compare_lines(b, a) when two lines shared a prefix ending just before "**". That violated antisymmetry, so Vec::sort_by produced different orderings on different platforms, breaking "CODEOWNERS out of date" validation. Compare path components left-to-right with "**" treated as a sentinel that sorts before any non-"**" component, falling back to full-line lexical compare as a deterministic tiebreaker. The shared comparator is reused by codeowners_file_parser, so both generation and parse agree.
- Rename the antisymmetry sweep so the name matches what it asserts. - Add a transitivity sweep over the same special-character set; this is the property that was actually missing from coverage of the Ord contract. - Add a length-asymmetry case (shorter path vs longer extension) and an equal-path tiebreaker case, exercising the (None, Some) / (Some, None) and full-line fallback arms.
perryqh
reviewed
May 18, 2026
| assert_eq!(compare_lines(&enabled, &other), compare_lines(&disabled, &other)); | ||
| assert_eq!(compare_lines(&other, &enabled), compare_lines(&other, &disabled)); | ||
| } | ||
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perryqh
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May 18, 2026
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dduugg
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Jun 10, 2026
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Summary
codeowners-rsgenerates nondeterministicCODEOWNERSordering due to invalid comparator incompare_lines#105:compare_linesinsrc/ownership/file_generator.rswas not antisymmetric, soVec::sort_byproduced different CODEOWNERS orderings on macOS vs Linux for the same input.**(e.g./foo/**/*bar*and/foo/**/baz/**/*), the old comparator returnedLessin both directions, leaving sort output platform/build dependent.**is treated as a sentinel that sorts before any non-**component, with full-line lexical compare as a deterministic tiebreaker. The shared comparator is reused bycodeowners_file_parser, so generated and parsed orderings agree.Test plan
cargo test— full suite passes (existing sort tests unchanged)cargo clippy --all-targets --all-features— cleancargo fmt --all -- --check— clean#prefix on disabled entries does not perturb path ordering