Squash Commits Skill

Automate squashing of WIP commits into logical groups with proper commit messages.

Workflow

1. •

   Identify base branch: Determine the branch to rebase onto (usually main or master)

2. •

   Analyze commits: Run git log --oneline BASE..HEAD to list commits to squash

3. •

   Propose groupings: Analyze commit messages and propose logical groups based on:

   • •Related file changes
   • •Feature/fix boundaries
   • •Commit message patterns (WIP, fixup, etc.)
4. •

   Show proposed messages: Display the full commit message for each group, get user approval

5. •

   Create backup: git branch backup-before-squash-$(date +%Y%m%d-%H%M%S)

6. •

   Stash changes: git stash if there are uncommitted changes

7. •

   Move untracked files: If data files block rebase, temporarily move them

8. •

   Execute rebase: Use automated rebase with fixup + exec pattern

9. •

   Verify: git diff backup-branch should be empty

Technical Details

Why fixup + exec, not squash

• •squash opens interactive editor for each squash group
• •fixup discards message, then exec git commit --amend -F file sets final message
• •Fully automated, no editor interaction needed

Rebase Editor Script Pattern

#!/bin/bash
# Dynamically generated rebase-editor.sh
cat > "$1" << 'EOF'
pick abc1234 First commit of group 1
fixup def5678 WIP: more work
fixup ghi9012 WIP: almost done
exec git commit --amend -F /path/to/message1.txt

pick jkl3456 First commit of group 2
fixup mno7890 WIP: feature B
exec git commit --amend -F /path/to/message2.txt
EOF

Message File Format

Create .rebase-messages/ directory with numbered message files:

• •01-group-name.txt - First group's commit message
• •02-group-name.txt - Second group's commit message

Each file contains the full commit message including:

• •Subject line (50 chars max)
• •Blank line
• •Body (wrapped at 72 chars)
• •Co-Authored-By if applicable

Execution Commands

# Create message directory
mkdir -p .rebase-messages

# Create backup
git branch backup-before-squash-$(date +%Y%m%d-%H%M%S)

# Stash if needed
git stash

# Run rebase
GIT_SEQUENCE_EDITOR="./rebase-editor.sh" git rebase -i BASE_BRANCH

# Verify (should be empty)
git diff backup-before-squash-*

# Clean up on success
rm -rf .rebase-messages rebase-editor.sh
git branch -D backup-before-squash-*  # Only after verification

Verification Checklist

• • git log --oneline BASE..HEAD shows expected commit count
• • git diff backup-branch is empty (no code changes)
• • Each commit message follows Conventional Commits format
• • No WIP/fixup/squash commits remain