git log: Usage, Options & Common CI Errors

By Daniel Zoghalchali·Latchkey

git log walks the commit history from a starting point, formatted however you need.

Log is the workhorse for inspecting history and generating changelogs. Custom --pretty formats keep output stable for scripts.

What it does

git log lists commits reachable from a given ref (HEAD by default), in reverse-chronological order, with configurable formatting and filtering.

Common usage

Terminal

git log --oneline --graph --decorate
git log -n 5
git log --pretty=format:"%h %s (%an)"
git log main..feature         # commits in feature not in main
git log --since="2 weeks ago" -- path/

Options

Flag	What it does
--oneline	One compact line per commit
--graph	ASCII branch/merge graph
--pretty=format:<fmt>	Custom, stable output format
-n <count> / -<count>	Limit number of commits
--since / --until / --author	Filter by date or author

Common errors in CI

fatal: your current branch 'main' does not have any commits yet - a fresh repo. With a shallow clone, log shows only the fetched commits, so a range like main..feature can look empty or wrong; deepen with git fetch --unshallow or fetch-depth: 0.

Using this in CI

CI checkouts are shallow and detached by default, which changes the answer this command gives you. Commands that read history, branch names, or tags need the checkout configured for it.

.github/workflows/ci.yml

- uses: actions/checkout@v4
  with:
    fetch-depth: 0   # history, tags, and git describe all need this

- run: |
    git rev-parse --is-shallow-repository   # expect false
    git rev-parse --abbrev-ref HEAD          # prints HEAD when detached

Frequently asked questions

git log: Usage, Options & Common CI Errors?