Yes, I agree, `git ls-files` can indeed be faster than just `rg --files`. On my Chromium checkout:

    $ hyperfine --output pipe 'rg --files' 'git ls-files'
    Benchmark 1: rg --files
      Time (mean ± σ):     141.2 ms ±   7.1 ms    [User: 1134.5 ms, System: 376.3 ms]
      Range (min … max):   128.7 ms … 154.8 ms    20 runs

    Benchmark 2: git ls-files
      Time (mean ± σ):      54.9 ms ±   1.7 ms    [User: 41.7 ms, System: 13.1 ms]
      Range (min … max):    52.2 ms …  62.0 ms    54 runs

    Summary
      git ls-files ran
        2.57 ± 0.15 times faster than rg --files

But the semantics here are important, because ripgrep doesn't only try to approximate `git ls-files`. It also needs to deal with `.rgignore` and `.ignore`. And no git repository state will help there. ripgrep also supports respecting `.gitignore` even when it isn't inside a git repository.