git-advanced

name	git-advanced
description	Advanced Git operations including rebase, cherry-pick, bisect, reflog, and recovery. Use when user asks to "rebase branch", "cherry-pick commit", "find bug with bisect", "recover lost commit", "squash commits", "fix git history", "interactive rebase", or any advanced git tasks.

Git Advanced

Advanced Git operations and recovery techniques.

Interactive Rebase

# Rebase last N commits
git rebase -i HEAD~5

# Rebase onto branch
git rebase -i main

# Commands in interactive editor:
# pick   = keep commit as-is
# reword = keep commit, edit message
# edit   = pause for amending
# squash = combine with previous commit
# fixup  = combine with previous, discard message
# drop   = remove commit

# Squash last 3 commits into one
git rebase -i HEAD~3
# Change 'pick' to 'squash' for commits 2 and 3

# Abort if something goes wrong
git rebase --abort

# Continue after resolving conflicts
git rebase --continue

# Skip current commit
git rebase --skip

Cherry-Pick

# Pick single commit
git cherry-pick abc1234

# Pick range of commits
git cherry-pick abc1234..def5678

# Pick without committing (stage only)
git cherry-pick --no-commit abc1234

# Pick from another branch
git cherry-pick feature-branch~3  # 3rd commit from tip

# Resolve conflicts and continue
git cherry-pick --continue

# Abort
git cherry-pick --abort

Bisect

# Start bisect
git bisect start

# Mark current as bad
git bisect bad

# Mark known good commit
git bisect good v1.0.0

# Git checks out middle commit - test it, then:
git bisect good    # If this commit works
git bisect bad     # If this commit is broken

# Repeat until Git finds the culprit

# End bisect
git bisect reset

# Automated bisect with test command
git bisect start HEAD v1.0.0
git bisect run npm test
# Git automatically finds the first bad commit

# Automated with script
git bisect run ./test-script.sh
# Script must exit 0 (good) or 1 (bad)

Stash

# Save work in progress
git stash
git stash push -m "work on feature X"

# Stash specific files
git stash push -m "partial" path/to/file.js

# Include untracked files
git stash -u
git stash --include-untracked

# List stashes
git stash list

# Apply stash
git stash pop          # Apply and remove
git stash apply        # Apply and keep
git stash pop stash@{2}  # Specific stash

# View stash contents
git stash show -p stash@{0}

# Create branch from stash
git stash branch new-branch stash@{0}

# Drop stash
git stash drop stash@{0}
git stash clear        # Remove all stashes

Reflog (Recovery)

# View reflog
git reflog
git reflog show HEAD
git reflog show main

# Each entry shows HEAD position at that point
# HEAD@{0} = current
# HEAD@{1} = previous position

# Recover after hard reset
git reflog
# Find the commit hash before the reset
git reset --hard HEAD@{2}

# Recover deleted branch
git reflog
# Find last commit of deleted branch
git checkout -b recovered-branch abc1234

# Recover after bad rebase
git reflog
# Find the commit before rebase started
git reset --hard HEAD@{5}

# Reflog expires after 90 days (default)

Reset vs Revert

# Reset (moves HEAD, rewrites history)
git reset --soft HEAD~1    # Undo commit, keep changes staged
git reset --mixed HEAD~1   # Undo commit, keep changes unstaged (default)
git reset --hard HEAD~1    # Undo commit, discard changes

# Revert (creates new commit, safe for shared branches)
git revert abc1234
git revert HEAD~3..HEAD    # Revert range
git revert --no-commit abc1234  # Stage without committing

# Revert a merge commit
git revert -m 1 abc1234   # Keep parent 1 (usually main)

Worktrees

# Create linked worktree
git worktree add ../project-hotfix hotfix-branch
git worktree add ../project-review origin/feature-branch

# List worktrees
git worktree list

# Remove worktree
git worktree remove ../project-hotfix

# Prune stale worktrees
git worktree prune

Log & History

# Compact log
git log --oneline --graph --all

# Search commits by message
git log --grep="fix bug"

# Search commits by code change
git log -S "functionName"           # Pickaxe (added/removed)
git log -G "pattern"                # Regex in diff

# Show commits that changed a file
git log --follow -- path/to/file.js

# Show who changed each line
git blame path/to/file.js
git blame -L 10,20 path/to/file.js  # Lines 10-20

# Diff between branches
git diff main..feature
git diff main...feature              # Changes since fork point

# Show files changed between commits
git diff --name-only HEAD~5 HEAD

Cleanup

# Remove untracked files (dry run first!)
git clean -n              # Preview
git clean -f              # Delete files
git clean -fd             # Delete files and directories
git clean -fx             # Delete ignored files too

# Garbage collection
git gc
git gc --aggressive

# Remove old reflog entries
git reflog expire --expire=30.days --all

Common Workflows

# Squash merge (clean history)
git checkout main
git merge --squash feature-branch
git commit -m "Add feature X"

# Rebase before merge (linear history)
git checkout feature
git rebase main
git checkout main
git merge feature   # Fast-forward

# Fixup workflow
git commit --fixup=abc1234
git rebase -i --autosquash main

Reference

For recovery techniques and reflog patterns: references/recovery.md