AI's "gitignored" claim checked with Git 2.55.0.windows.5: 1 of 3 right

A walkthrough rather than a product announcement, its central point is that two separate Git facts decide whether a file is 'excluded': whether Git tracks it, and whether a .gitignore rule matches it. In the test repository, app.env was committed before *.env was added, so git ls-files still listed it. Only git check-ignore -v --no-index, which ignores tracking status, revealed that line 1 (*.env) was the rule that would apply if the file were untracked.

For debug.log the situation was different again: no rule matched it and it was untracked, identified through the ?? marker in git status --short. That distinction matters because git add . would pick up debug.log, while build/ appeared only as !! when --ignored was added, confirming it was excluded.

The piece also flags a cleanup step and its limit. Running git rm --cached app.env removed it from git ls-files and made the *.env rule effective, but the file's content remained readable via git show HEAD:app.env, so history is a separate decision. It closes by noting Git output can vary by version and configuration, and that the suggested prompt for having an AI run these checks was not tested.