--- name: using-git-worktrees description: Use Git worktrees to create parallel working directories safely; avoid branch-switch contamination. --- # Using Git Worktrees ## Overview Git worktree allows mounting multiple working directories onto the same repository simultaneously, each mapped to a different branch. This is ideal for parallel development and hotfixes. ## Workspace Selection Principles - Manage them centrally outside the repo or in a dedicated folder (e.g., `../wt-`). - Name them with task semantics (feature/hotfix + short name). - Avoid confusing or overwriting existing workspaces. ## Safety Checks 1. **Detect nesting first** — do not create a worktree from inside another worktree or a submodule: - You are already in a *linked* worktree if `git rev-parse --git-dir` differs from `git rev-parse --git-common-dir` (they match in the main worktree). `cd` to the main worktree before adding. - You are in a submodule if `git rev-parse --show-superproject-working-tree` is non-empty. Operate on the intended repo, not the submodule. 2. Ensure the primary workspace is clean (prevent taking uncommitted changes). 3. List existing worktrees first: `git worktree list`. 4. Check that the target directory does not exist or is empty. 5. **Keep the worktree path out of the tracked tree** — prefer a sibling dir (`../wt-`). If it must live inside the repo, verify it is ignored first: `git check-ignore -q ` (exit 0 = ignored). A non-ignored in-repo worktree pollutes the parent's `git status` and can be committed by accident. 6. Confirm branch naming and tracking strategies. ## Setup Workflow 1. Create a branch and add a worktree: - `git worktree add ../wt- -b ` 2. Switch to the new directory and run a baseline test. 3. Develop, commit, and verify independently in that directory. 4. Remove the worktree when finished (if no longer needed): - `git worktree remove ../wt-` ## Common Mistakes - Committing in the wrong worktree. - Deleting a worktree without confirming if the branch should be preserved. - Chaotic directory naming, leading to unclear task mapping.