harn file-history

harn file-history [options] <path>

A concise per-file git log for one path: total commits, distinct authors, first/last touched dates, cumulative line impact, and the N most-recent commits with their +/- counts. Reach for it when you want the shape of a file’s history without scrolling git log or reading the whole thing.

It follows renames (git log --follow) and is repo-aware: the log runs inside whichever repository the path’s directory resolves to, so a file inside a nested checkout gets that checkout’s history rather than the outer one’s.

Options

Flag	Description
--limit <n>	Show the N most-recent commits (default 20).
--since <date>	Restrict to commits since DATE — accepts git’s date syntax ('30 days ago', '2026-01-01').
--author <pat>	Filter to commits whose author matches PAT (substring).
--json	Structured JSON envelope instead of the text report.

Examples

# Default: summary stats + 20 most-recent commits
harn file-history src/index.ts

# Just the last 5 commits
harn file-history src/index.ts --limit 5

# Only what changed in the last month
harn file-history README.md --since "30 days ago"

# One author's touches on a file
harn file-history src/config.ts --author jane

# Machine-readable output
harn file-history src/index.ts --json

Output

The default report leads with a summary line (N commits by M authors, +added/-removed lines), the first and last commit shas with dates, a top-authors list, and the recent-commits table (short sha, date, line delta, author, subject).

The --json envelope carries { file, repo, total_commits, authors[], first_commit, last_commit, total_added, total_removed, commits[] }, where each entry in commits[] has sha, short_sha, author, date, subject, added, and removed.

Notes

Merge commits are excluded, so the line-impact totals reflect real edits rather than merge churn. A path with no recorded history reports zero commits rather than erroring.