Imported from pdas544/online-exam-app-laravel (.opencode/skills/using-git-worktrees/SKILL.md). Install upstream with npx skills add pdas544/online-exam-app-laravel --skill using-git-worktrees. Copyright stays with the author.

Using Git Worktrees

Overview

Ensure work happens in an isolated workspace. Prefer your platform's native worktree tools. Fall back to manual git worktrees only when no native tool is available.

Core principle: Detect existing isolation first. Then use native tools. Then fall back to git. Never fight the harness.

Announce at start: "I'm using the using-git-worktrees skill to set up an isolated workspace."

Step 0: Detect Existing Isolation

Before creating anything, check if you are already in an isolated workspace.

GIT_DIR=$(cd "$(git rev-parse --git-dir)" 2>/dev/null && pwd -P)
GIT_COMMON=$(cd "$(git rev-parse --git-common-dir)" 2>/dev/null && pwd -P)
BRANCH=$(git branch --show-current)

Submodule guard: GIT_DIR != GIT_COMMON is also true inside git submodules. Before concluding "already in a worktree," verify you are not in a submodule:

# If this returns a path, you're in a submodule, not a worktree — treat as normal repo
git rev-parse --show-superproject-working-tree 2>/dev/null

If GIT_DIR != GIT_COMMON (and not a submodule): You are already in a linked worktree. Skip to Step 2 (Project Setup). Do NOT create another worktree.

Report with branch state:

• On a branch: "Already in isolated workspace at <path> on branch <name>."
• Detached HEAD: "Already in isolated workspace at <path> (detached HEAD, externally managed). Branch creation needed at finish time."

If GIT_DIR == GIT_COMMON (or in a submodule): You are in a normal repo checkout. Ask for consent before creating a worktree — honor any existing declared preference without asking. If the user declines, work in place and skip to Step 2.

Step 1: Create Isolated Workspace

1a. Native Worktree Tools (preferred)

If you have a way to create a worktree (tool, /worktree command, --worktree flag), use it and skip to Step 2. Native tools handle directory placement, branch creation, and cleanup automatically.

Only proceed to Step 1b if you have no native worktree tool available.

1b. Git Worktree Fallback

Only use this if Step 1a does not apply. Create a worktree manually using git.

Directory Selection

1. Check instructions for a declared worktree directory preference. If specified, use it without asking.
2. Check for an existing project-local worktree directory: .worktrees/ (preferred) or worktrees/. If both exist, .worktrees wins.
3. Default: .worktrees/ at the project root.

Safety Verification (project-local directories only)

MUST verify directory is ignored before creating worktree:

git check-ignore -q .worktrees 2>/dev/null || git check-ignore -q worktrees 2>/dev/null

If NOT ignored: Add to .gitignore, commit the change, then proceed.

Create the Worktree

path="$LOCATION/$BRANCH_NAME"

git worktree add "$path" -b "$BRANCH_NAME"
cd "$path"

Sandbox fallback: If git worktree add fails with a permission error, work in the current directory instead. Then run setup and baseline tests in place.

Step 2: Project Setup

Auto-detect and run appropriate setup:

# Node.js
if [ -f package.json ]; then npm install; fi

# PHP / Laravel
if [ -f composer.json ]; then composer install; fi
if [ -f artisan ]; then php artisan config:clear; fi

# Rust
if [ -f Cargo.toml ]; then cargo build; fi

# Python
if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
if [ -f pyproject.toml ]; then poetry install; fi

# Go
if [ -f go.mod ]; then go mod download; fi

Step 3: Verify Clean Baseline

Run tests to ensure workspace starts clean (this project: composer run test).

If tests fail: Report failures, ask whether to proceed or investigate.

If tests pass: Report ready.

Report

Worktree ready at <full-path>
Tests passing (<N> tests, 0 failures)
Ready to implement <feature-name>

Quick Reference

Common Rationalizations