git show <rev> -- <relPath> — the diff for one commit touching one file.
rev must already be validated as a hex commit hash by the caller (never
a ref expression like HEAD~1 or main^, which could be abused as an
argument-injection vector); relPath must already be repo-relative.
Returns null when the vault isn't a git repo or the commit/diff can't be
produced.
git show <rev> -- <relPath>— the diff for one commit touching one file.revmust already be validated as a hex commit hash by the caller (never a ref expression likeHEAD~1ormain^, which could be abused as an argument-injection vector);relPathmust already be repo-relative. Returns null when the vault isn't a git repo or the commit/diff can't be produced.