--- name: git-advanced-workflows description: Master advanced Git workflows including rebasing, cherry-picking, bisect, worktrees, and reflog to maintain clean history and recover from any situation. Use when managing complex Git histories, collaborating on feature branches, or troubleshooting repository issues. --- # Git Advanced Workflows Master advanced Git techniques to maintain clean history, collaborate effectively, and recover from any situation with confidence. ## When to Use This Skill - Cleaning up commit history before merging - Applying specific commits across branches - Finding commits that introduced bugs - Working on multiple features simultaneously - Recovering from Git mistakes or lost commits - Managing complex branch workflows - Preparing clean PRs for review - Synchronizing diverged branches ## Core Concepts ### 1. Interactive Rebase Interactive rebase is the Swiss Army knife of Git history editing. **Common Operations:** - `pick`: Keep commit as-is - `reword`: Change commit message - `edit`: Amend commit content - `squash`: Combine with previous commit - `fixup`: Like squash but discard message - `drop`: Remove commit entirely **Basic Usage:** ```bash # Rebase last 5 commits git rebase -i HEAD~5 # Rebase all commits on current branch git rebase -i $(git merge-base HEAD main) # Rebase onto specific commit git rebase -i abc123 ``` ### 2. Cherry-Picking Apply specific commits from one branch to another without merging entire branches. ```bash # Cherry-pick single commit git cherry-pick abc123 # Cherry-pick range of commits (exclusive start) git cherry-pick abc123..def456 # Cherry-pick without committing (stage changes only) git cherry-pick -n abc123 # Cherry-pick and edit commit message git cherry-pick -e abc123 ``` ### 3. Git Bisect Binary search through commit history to find the commit that introduced a bug. ```bash # Start bisect git bisect start # Mark current commit as bad git bisect bad # Mark known good commit git bisect good v1.0.0 # Git will checkout middle commit - test it # Then mark as good or bad git bisect good # or: git bisect bad # Continue until bug found # When done git bisect reset ``` **Automated Bisect:** ```bash # Use script to test automatically git bisect start HEAD v1.0.0 git bisect run ./test.sh # test.sh should exit 0 for good, 1-127 (except 125) for bad ``` ### 4. Worktrees Work on multiple branches simultaneously without stashing or switching. ```bash # List existing worktrees git worktree list # Add new worktree for feature branch git worktree add ../project-feature feature/new-feature # Add worktree and create new branch git worktree add -b bugfix/urgent ../project-hotfix main # Remove worktree git worktree remove ../project-feature # Prune stale worktrees git worktree prune ``` ### 5. Reflog Your safety net - tracks all ref movements, even deleted commits. ```bash # View reflog git reflog # View reflog for specific branch git reflog show feature/branch # Restore deleted commit git reflog # Find commit hash git checkout abc123 git branch recovered-branch # Restore deleted branch git reflog git branch deleted-branch abc123 ``` ## Practical Workflows ### Workflow 1: Clean Up Feature Branch Before PR ```bash # Start with feature branch git checkout feature/user-auth # Interactive rebase to clean history git rebase -i main # Example rebase operations: # - Squash "fix typo" commits # - Reword commit messages for clarity # - Reorder commits logically # - Drop unnecessary commits # Force push cleaned branch (safe if no one else is using it) git push --force-with-lease origin feature/user-auth ``` ### Workflow 2: Apply Hotfix to Multiple Releases ```bash # Create fix on main git checkout main git commit -m "fix: critical security patch" # Apply to release branches git checkout release/2.0 git cherry-pick abc123 git checkout release/1.9 git cherry-pick abc123 # Handle conflicts if they arise git cherry-pick --continue # or git cherry-pick --abort ``` ### Workflow 3: Find Bug Introduction ```bash # Start bisect git bisect start git bisect bad HEAD git bisect good v2.1.0 # Git checks out middle commit - run tests npm test # If tests fail git bisect bad # If tests pass git bisect good # Git will automatically checkout next commit to test # Repeat until bug found # Automated version git bisect start HEAD v2.1.0 git bisect run npm test ``` ### Workflow 4: Multi-Branch Development ```bash # Main project directory cd ~/projects/myapp # Create worktree for urgent bugfix git worktree add ../myapp-hotfix hotfix/critical-bug # Work on hotfix in separate directory cd ../myapp-hotfix # Make changes, commit git commit -m "fix: resolve critical bug" git push origin hotfix/critical-bug # Return to main work without interruption cd ~/projects/myapp git fetch origin git cherry-pick hotfix/critical-bug # Clean up when done git worktree remove ../myapp-hotfix ``` ### Workflow 5: Recover from Mistakes ```bash # Accidentally reset to wrong commit git reset --hard HEAD~5 # Oh no! # Use reflog to find lost commits git reflog # Output shows: # abc123 HEAD@{0}: reset: moving to HEAD~5 # def456 HEAD@{1}: commit: my important changes # Recover lost commits git reset --hard def456 # Or create branch from lost commit git branch recovery def456 ``` ## Advanced Techniques ### Rebase vs Merge Strategy **When to Rebase:** - Cleaning up local commits before pushing - Keeping feature branch up-to-date with main - Creating linear history for easier review **When to Merge:** - Integrating completed features into main - Preserving exact history of collaboration - Public branches used by others ```bash # Update feature branch with main changes (rebase) git checkout feature/my-feature git fetch origin git rebase origin/main # Handle conflicts git status # Fix conflicts in files git add . git rebase --continue # Or merge instead git merge origin/main ``` ### Autosquash Workflow Automatically squash fixup commits during rebase. ```bash # Make initial commit git commit -m "feat: add user authentication" # Later, fix something in that commit # Stage changes git commit --fixup HEAD # or specify commit hash # Make more changes git commit --fixup abc123 # Rebase with autosquash git rebase -i --autosquash main # Git automatically marks fixup commits ``` ### Split Commit Break one commit into multiple logical commits. ```bash # Start interactive rebase git rebase -i HEAD~3 # Mark commit to split with 'edit' # Git will stop at that commit # Reset commit but keep changes git reset HEAD^ # Stage and commit in logical chunks git add file1.py git commit -m "feat: add validation" git add file2.py git commit -m "feat: add error handling" # Continue rebase git rebase --continue ``` ### Partial Cherry-Pick Cherry-pick only specific files from a commit. ```bash # Show files in commit git show --name-only abc123 # Checkout specific files from commit git checkout abc123 -- path/to/file1.py path/to/file2.py # Stage and commit git commit -m "cherry-pick: apply specific changes from abc123" ``` ## Best Practices 1. **Always Use --force-with-lease**: Safer than --force, prevents overwriting others' work 2. **Rebase Only Local Commits**: Don't rebase commits that have been pushed and shared 3. **Descriptive Commit Messages**: Future you will thank present you 4. **Atomic Commits**: Each commit should be a single logical change 5. **Test Before Force Push**: Ensure history rewrite didn't break anything 6. **Keep Reflog Aware**: Remember reflog is your safety net for 90 days 7. **Branch Before Risky Operations**: Create backup branch before complex rebases ```bash # Safe force push git push --force-with-lease origin feature/branch # Create backup before risky operation git branch backup-branch git rebase -i main # If something goes wrong git reset --hard backup-branch ``` ## Common Pitfalls - **Rebasing Public Branches**: Causes history conflicts for collaborators - **Force Pushing Without Lease**: Can overwrite teammate's work - **Losing Work in Rebase**: Resolve conflicts carefully, test after rebase - **Forgetting Worktree Cleanup**: Orphaned worktrees consume disk space - **Not Backing Up Before Experiment**: Always create safety branch - **Bisect on Dirty Working Directory**: Commit or stash before bisecting ## Recovery Commands ```bash # Abort operations in progress git rebase --abort git merge --abort git cherry-pick --abort git bisect reset # Restore file to version from specific commit git restore --source=abc123 path/to/file # Undo last commit but keep changes git reset --soft HEAD^ # Undo last commit and discard changes git reset --hard HEAD^ # Recover deleted branch (within 90 days) git reflog git branch recovered-branch abc123 ``` ## Resources - **references/git-rebase-guide.md**: Deep dive into interactive rebase - **references/git-conflict-resolution.md**: Advanced conflict resolution strategies - **references/git-history-rewriting.md**: Safely rewriting Git history - **assets/git-workflow-checklist.md**: Pre-PR cleanup checklist - **assets/git-aliases.md**: Useful Git aliases for advanced workflows - **scripts/git-clean-branches.sh**: Clean up merged and stale branches