Git Cheatsheet

Top commands.

Reading history

git log is the entry point to every history investigation. The right flags turn it into a precision tool.

git log --oneline -20: Per-repo the recent-commit summary. Last 20 commits, one line each.
git log --all --graph --oneline --decorate: Per-repo the cross-branch graph. Useful for understanding merge history.
git log --grep='fix bug' --since='2 weeks ago': Per-search the filtered history. Search by message and time.
git log -S'pattern' -- file.py: Per-pattern the pickaxe search. The discipline finds when a string entered or left.

Understanding code

blame, log -p, show are the daily archaeology surface. Each answers a different "why is this here" question.

git blame file.py: Per-line the author and commit. Often the first step in debugging legacy code.
git log -p -- file.py: Per-file the full diff history. Track how it evolved.
git show HEAD~3: Per-commit the full diff three back from HEAD.
git blame -L 10,20 file.py: Per-range the focused blame. The discipline supports investigation of a specific block.

Branch operations

switch and branch are the modern primitives. Use switch over checkout for new branch operations.

git switch -c feature/x: Per-feature the new branch. Modern alternative to git checkout -b.
git switch main: Per-context the branch change. Switches branches without creating.
git branch -d old-branch: Per-cleanup the merged-branch deletion. -D for force delete.
git branch --merged main: Per-cleanup the already-merged list. The discipline supports periodic pruning.

Rewriting history

Rebase is its own discipline. Interactive, onto-main, pull-rebase each map to a specific cleanup.

git rebase -i HEAD~5: Per-cleanup the interactive rebase of last 5 commits. Squash, reword, drop, reorder.
git rebase main: Per-feature the replay onto latest main. Linear history.
git pull --rebase: Per-pull the rebase instead of merge. Cleaner history for shared branches.
git rebase --autosquash: Per-cleanup the fixup-aware rebase. The discipline supports fixup-marked commits.

Recovery

Recovery is the last-resort discipline. reflog, reset, fsck.

git reflog: Per-repo the local-action log. Recover from any mistake within reflog window.
git reset --hard ORIG_HEAD: Per-incident the revert-last-operation. ORIG_HEAD is what HEAD was before the last move.
git fsck --lost-found: Per-repo the dangling-object finder. Last-resort recovery.
git stash list / pop: Per-context the stashed-change recovery. The discipline supports interrupt-driven workflows.