[somewhatabstract]

Stacked on #2704. This finishes removing the Rust code that was ported from git. read_gitignore_patterns.rs, parse_gitignore_pattern.rs, trim_gitignore_trailing_spaces.rs, gitignore_pattern_matches.rs and the matching logic in IgnoreFile were line-for-line ports of functions from git's dir.c, which is GPL v2.

The same clean-room agent that wrote the glob matcher wrote the replacement behind IgnoreFile's unchanged public API. It worked only from the documented gitignore behaviour, our own code and tests, and git 2.56 run as a black box.

• IgnoreFile: gitignore_parse and gitignore_parse_line read the file. They handle comments, escapes, trailing spaces, CRLF, a BOM, NUL bytes, negation, and folder-only and anchored patterns. gitignore_decide_path decides as git does: a file inside an ignored folder stays ignored, and otherwise the last matching pattern decides.

• Speed: each pattern is compiled once with compile_glob and stored. Matching then:

  • stops as soon as no match is possible;
  • updates one list in place instead of allocating one for each token;
  • works out a path's last name once rather than once per pattern.

  These address the review of Replace the Rust glob matcher with a clean-room implementation #2704. glob_matches is gone, since nothing outside the tests called it.

• Pinned to git: __conformance__/glob-vectors.json holds 756 cases with git's answers. A test inside the crate checks the compiled matcher against every case. Nothing new is public.

Part of #2615.

Test plan

• The clean-room agent's comparisons with git 2.56: 378,114 path decisions and 600,000 glob cases, after the review fixes. The random ignore files now often put NUL bytes next to carriage returns, which is the case the first review caught.
• My own comparisons: 150,000 path decisions through the real IgnoreFile API, with files on disk, and 500,000 glob cases. Every one agreed.
• Existing tests: ignore-vectors.json and the IgnoreFile and is_allowed_by_ignore_files tests still pass.

🤖 Generated with Claude Code

https://claude.ai/code/session_01QjLhVH1NnUc7MzCSYLd8Yn

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🦋 Changeset detected

Latest commit: b0439e4

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[codecov]

Bundle Report

Bundle size has no change ✅

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (24f0939) to head (b0439e4).

Additional details and impacted files

@@                              Coverage Diff                              @@
##           claude/jolly-galileo-72zesp-cleanroom-glob     #2705    +/-   ##
=============================================================================
  Coverage                                      100.00%   100.00%            
=============================================================================
  Files                                             106       111     +5     
  Lines                                            3633      3830   +197     
  Branches                                         2840      3038   +198     
=============================================================================
+ Hits                                             3633      3830   +197     

Flag	Coverage Δ
rust	100.00% <100.00%> (ø)
typescript	100.00% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...t/crates/checksync-core/src/advance_any_folders.rs	100.00% <100.00%> (ø)
...rates/checksync-core/src/advance_glob_positions.rs	100.00% <100.00%> (ø)
rust/crates/checksync-core/src/advance_one_byte.rs	100.00% <100.00%> (ø)
rust/crates/checksync-core/src/advance_star.rs	100.00% <100.00%> (ø)
rust/crates/checksync-core/src/bytes_before_nul.rs	100.00% <100.00%> (ø)
rust/crates/checksync-core/src/compile_glob.rs	100.00% <100.00%> (ø)
...crates/checksync-core/src/compiled_glob_matches.rs	100.00% <100.00%> (ø)
...crates/checksync-core/src/gitignore_decide_path.rs	100.00% <100.00%> (ø)
.../crates/checksync-core/src/gitignore_last_match.rs	100.00% <100.00%> (ø)
rust/crates/checksync-core/src/gitignore_parse.rs	100.00% <100.00%> (ø)
... and 6 more

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[somewhatabstract]

LGTM