gh-cskiro-claudex/skills/devops/git-worktree-setup/modes/mode1-single-worktree.md

Mode 1: Single Worktree Creation

Overview

This mode creates a single git worktree for parallel development. Use this when the user wants to work on one additional branch alongside their current work.

When to Use

• User mentions creating "a worktree" (singular)
• User specifies one branch name
• User says "I need to work on [branch]"
• Default mode when unclear

Workflow

Phase 0: Prerequisites & Validation

Step 0.1: Verify Git Repository

git rev-parse --is-inside-work-tree

Expected Output:

true

If fails:

• Stop immediately
• Error: "Not in a git repository. Please navigate to your project root and try again."

Step 0.2: Get Repository Information

# Get repository name
basename $(git rev-parse --show-toplevel)

# Get current branch
git branch --show-current

Store:

• REPO_NAME: Repository name
• CURRENT_BRANCH: Current branch

Step 0.3: Check Working Directory Status

git status --porcelain

If output exists:

• Warning: "You have uncommitted changes in your current worktree:"
• Show: git status --short
• Ask: "Continue creating worktree anyway? This won't affect your changes."
• If user declines → Stop

If clean:

• Proceed silently

Step 0.4: Check Existing Worktrees

git worktree list

Purpose:

• Show user current worktree state
• Detect conflicts before creation
• Store for later reference

---

Phase 1: Gather Information

Step 1.1: Extract Branch Name

From user request:

• "create worktree for feature-auth"
• "set up worktree for bugfix-123"
• "I need a worktree for experiment-new-ui"

Extract:

• BRANCH_NAME: The branch to work on

If unclear:

• Ask: "What branch name should I use for the worktree?"

Step 1.2: Determine Branch Type

Check if branch exists:

git show-ref --verify refs/heads/$BRANCH_NAME 2>/dev/null

If exits (exit code 0):

• BRANCH_TYPE: "existing"
• Message: "Found existing branch: $BRANCH_NAME"

If doesn't exist:

• BRANCH_TYPE: "new"
• Message: "Will create new branch: $BRANCH_NAME"

Also check remote:

git show-ref --verify refs/remotes/origin/$BRANCH_NAME 2>/dev/null

If exists on remote but not local:

• Offer: "Branch exists on remote. Track remote branch or create new local?"
• Default: Track remote

Step 1.3: Determine Worktree Location

Default location:

../$REPO_NAME-$BRANCH_NAME

Example:

• Repo: myapp
• Branch: feature-auth
• Location: ../myapp-feature-auth

Ask user: "I'll create the worktree at: $DEFAULT_LOCATION" "Use this location? (yes/no/specify custom)"

Options:

• Yes → Use default
• No → Ask for custom path
• Custom → Use provided path

Store:

• WORKTREE_PATH: Final worktree location

Step 1.4: Check Directory Availability

if [ -d "$WORKTREE_PATH" ]; then
  echo "exists"
else
  echo "available"
fi

If exists:

• Error: "Directory already exists: $WORKTREE_PATH"
• Ask: "Remove it and continue? (yes/no)"
• If yes → rm -rf $WORKTREE_PATH (with confirmation)
• If no → Ask for different location

Step 1.5: Development Environment Setup

Check for package.json:

if [ -f "package.json" ]; then
  echo "found"
fi

If found:

• Default: "Setup development environment? (yes/no)" → yes
• Ask: "Install dependencies in new worktree?"

Store:

• SETUP_DEV: true/false

If no package.json:

• Skip dev setup questions
• SETUP_DEV: false

---

Phase 2: Create Worktree

Step 2.1: Execute Worktree Creation

For new branch:

git worktree add $WORKTREE_PATH -b $BRANCH_NAME

For existing branch:

git worktree add $WORKTREE_PATH $BRANCH_NAME

For tracking remote branch:

git worktree add $WORKTREE_PATH -b $BRANCH_NAME --track origin/$BRANCH_NAME

Expected Output:

Preparing worktree (new branch 'feature-auth')
HEAD is now at abc123 Initial commit

Monitor for errors:

• "fatal: invalid reference" → Branch doesn't exist
• "fatal: 'path' already exists" → Directory conflict
• "fatal: 'branch' is already checked out" → Branch in another worktree

If error:

• Stop and report error
• Provide fix suggestion
• Don't continue to next phase

Step 2.2: Verify Worktree Creation

git worktree list

Check output includes:

/path/to/worktree  abc123 [branch-name]

Verify directory:

ls -la $WORKTREE_PATH

Must see:

• .git file (not directory - points to parent)
• Project files

If verification fails:

• Error: "Worktree creation failed verification"
• Show: git worktree list
• Offer: "Try again with different settings?"
• Stop

Step 2.3: Confirm Success

Output:

✓ Worktree created successfully
  Location: $WORKTREE_PATH
  Branch: $BRANCH_NAME ($BRANCH_TYPE)
  Status: Ready

---

Phase 3: Setup Development Environment

Only if SETUP_DEV is true

Step 3.1: Navigate to Worktree

cd $WORKTREE_PATH

Step 3.2: Detect Package Manager

Check for lockfiles in priority order:

# Check pnpm
if [ -f "pnpm-lock.yaml" ]; then
  PKG_MANAGER="pnpm"
  INSTALL_CMD="pnpm install"
fi

# Check yarn
if [ -f "yarn.lock" ]; then
  PKG_MANAGER="yarn"
  INSTALL_CMD="yarn install"
fi

# Check bun
if [ -f "bun.lockb" ]; then
  PKG_MANAGER="bun"
  INSTALL_CMD="bun install"
fi

# Check npm
if [ -f "package-lock.json" ]; then
  PKG_MANAGER="npm"
  INSTALL_CMD="npm install"
fi

# Default to npm if no lockfile
if [ -z "$PKG_MANAGER" ]; then
  PKG_MANAGER="npm"
  INSTALL_CMD="npm install"
fi

Output:

Detected package manager: $PKG_MANAGER

Step 3.3: Run Installation

$INSTALL_CMD

Show progress:

Installing dependencies with $PKG_MANAGER...

Expected output (varies by manager):

• npm: "added X packages in Ys"
• pnpm: "Packages: +X"
• yarn: "Done in Xs"
• bun: "X packages installed"

Monitor for errors:

• Network failures
• Lockfile conflicts
• Disk space issues

If error:

• Show error message
• Suggest: "Installation failed. You can manually run $INSTALL_CMD in the worktree later."
• Mark: Dev environment setup failed
• Continue (don't stop entire process)

If success:

✓ Dependencies installed successfully

Step 3.4: Copy Environment Files (Optional)

Check for .env in parent:

if [ -f "../.env" ]; then
  echo "found"
fi

If found:

• Ask: "Copy .env file to worktree? (yes/no)"
• Default: Ask (don't assume - may contain secrets)

If yes:

cp ../.env .env

Output:

✓ Environment file copied

Other common files to check:

• .env.local
• .env.development
• .env.test

Step 3.5: Verify Development Setup

# Check node_modules exists
if [ -d "node_modules" ]; then
  echo "✓ Dependencies installed"
fi

# Try running a basic script (optional)
npm run build --dry-run 2>/dev/null && echo "✓ Build configuration valid"

Final status:

✓ Development environment ready
  Package manager: $PKG_MANAGER
  Dependencies: Installed
  Environment: Ready

---

Phase 4: Provide User Guidance

Step 4.1: Generate Summary

Create summary output:

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Worktree Created Successfully
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Location:   $WORKTREE_PATH
Branch:     $BRANCH_NAME (new/existing)
Base:       $BASE_BRANCH
Dev Setup:  ✓ Complete / ⊘ Skipped

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Next Steps
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

1. Navigate to worktree:
   cd $WORKTREE_PATH

2. Start Claude Code:
   claude

3. Begin development on $BRANCH_NAME

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Step 4.2: Show All Worktrees

git worktree list

Format output:

All Worktrees:
  /path/to/main        (main)          ← current
  $WORKTREE_PATH       ($BRANCH_NAME)  ← new

Highlight:

• Current worktree with ← current
• New worktree with ← new

Step 4.3: Provide Quick Reference Commands

Quick Reference:
  List worktrees:    git worktree list
  Remove worktree:   git worktree remove $WORKTREE_PATH
  Navigate:          cd $WORKTREE_PATH
  Return to main:    cd [original path]

Step 4.4: Offer Additional Actions

Ask user: "Would you like me to:

• Open the worktree in a new terminal
• Generate a setup script for future worktrees
• Show git commands for advanced management"

Based on response, provide appropriate outputs

---

Phase 5: Post-Creation Verification

Step 5.1: Final Checks

# Verify worktree is in list
git worktree list | grep -q "$WORKTREE_PATH"

# Verify directory exists and has files
[ -d "$WORKTREE_PATH" ] && [ "$(ls -A $WORKTREE_PATH)" ]

# Verify .git file exists
[ -f "$WORKTREE_PATH/.git" ]

All must pass

Step 5.2: Success Confirmation

Create success checklist:

✓ Worktree created at correct location
✓ Branch checked out properly
✓ Files visible in worktree directory
✓ Development environment ready (if requested)
✓ Worktree appears in git worktree list
✓ Ready for Claude Code session

If any fail:

• Report which check failed
• Provide troubleshooting steps
• Offer to retry or cleanup

---

Error Handling

Error: Not a Git Repository

Error: Not in a git repository

Solution:
1. Navigate to your project root
2. Verify with: git status
3. Try again

Error: Branch Already Checked Out

Error: Branch 'feature-x' is already checked out at '/path'

Solution:
1. List worktrees: git worktree list
2. Navigate to existing worktree, or
3. Remove existing worktree first:
   git worktree remove /path

Error: Directory Already Exists

Error: Directory already exists: /path/to/worktree

Solutions:
1. Use different location
2. Remove directory: rm -rf /path/to/worktree
3. Specify custom path when creating

Error: Installation Failed

Error: Dependency installation failed

Solutions:
1. Check network connection
2. Manually run in worktree:
   cd /path/to/worktree
   [package-manager] install
3. Check lockfile compatibility

---

Stop Conditions

Stop immediately if:

• Not in a git repository
• Worktree creation command fails
• Directory already exists and user declines removal
• User cancels during any confirmation

Continue with warnings if:

• Uncommitted changes in current worktree
• Dependency installation fails
• Environment file copy fails

---

Success Criteria

• Worktree created successfully
• Branch checked out
• Directory accessible
• Dev environment ready (if requested)
• User provided with clear next steps
• All verification checks passed

---

Example: Complete Flow

User: Create a worktree for feature-authentication