Commit

Git · Reference cheat sheet

📖 Overview

A commit records a snapshot of the staged index with metadata (author, message, parent). Prefer small, purposeful commits with clear messages; amend only when safe (unpushed, intentional).

🧩 Core concepts

• Snapshot model — commit points at a tree; parents form history.
• Message — subject (+ optional body); conventional prefixes (feat:, fix:) are team conventions.
• Amend — git commit --amend rewrites the latest commit (changes hash).
• Sign-off / GPG — -s / -S for DCO or signed commits when required.
• Empty commits — --allow-empty for CI triggers or markers (rare).
• Hooks — pre-commit / commit-msg can block or rewrite messages.

💡 Examples

# Commit staged changes
git commit -m "feat: add login form validation"

# Stage tracked files and commit
git commit -am "fix: handle null user in session"

# Amend message only
git commit --amend -m "feat: add login form validation"

# Amend and include newly staged files (unpushed only)
git add src/login.ts
git commit --amend --no-edit

# Show last commit
git log -1 --stat
git show HEAD

# Skip hooks only if you must (usually avoid)
# git commit --no-verify -m "wip"

⚠️ Pitfalls

• Amending a commit already pushed requires force-push — coordinate with the team.
• -a ignores untracked files — new files still need git add.
• Huge commits are hard to review and revert — split by concern.
• Never put secrets in commit messages or blobs; rewriting history later is painful.

🔗 Related

• Stage
• Branch
• Push
• Rebase
• Merge