dtsong/Git Rebase

Scope Constraints

• Destructive write operation — rewrites commit history by replaying commits onto a new base
• Fetches from remote to update the target branch before rebasing
• Does not push to remote — use push skill with --force-with-lease after rebase
• Does not resolve conflicts — use conflicts skill if rebase produces conflicts
• Should not be used on shared branches — only personal feature branches

Input Sanitization

• Target branch name: only alphanumeric characters, hyphens, underscores, and forward slashes. Reject spaces, .., shell metacharacters, or null bytes.
• Flags: only --continue, --abort accepted. Reject arbitrary strings.

/git-rebase - Rebase Onto Main

Rebase your feature branch onto the latest main for a clean, linear history.

Usage

/git-rebase              # Rebase onto main
/git-rebase develop      # Rebase onto develop
/git-rebase --continue   # Continue after resolving conflicts
/git-rebase --abort      # Abort rebase in progress

When to Use Rebase

• Before creating a PR: Clean history before review
• Updating feature branch: Alternative to merge for cleaner history
• Personal branches: When you're the only one working on the branch

When NOT to Rebase

• Shared branches: Never rebase branches others are working on
• Already pushed commits: Changes history that others may have
• After merge commits: Can cause complex conflicts

Workflow

Step 1: Pre-flight Checks

CURRENT=$(git branch --show-current)

# Cannot rebase main
if [ "$CURRENT" = "main" ] || [ "$CURRENT" = "master" ]; then
    echo "Cannot rebase main onto itself."
    exit 1
fi

# Check for uncommitted changes
if ! git diff --quiet || ! git diff --cached --quiet; then
    echo "You have uncommitted changes."
    echo "Stash or commit them first:"
    echo "  /git-stash"
    echo "  /commit"
    exit 1
fi

Step 2: Update Target Branch

# Fetch latest main
git fetch origin main

# Show what will happen
COMMITS=$(git log --oneline origin/main..HEAD | wc -l)
echo "Will rebase $COMMITS commits onto origin/main"

Step 3: Preview Potential Conflicts

# Files that might conflict
echo "Files modified in both branches:"
git diff --name-only origin/main...HEAD

Step 4: Execute Rebase

# Standard rebase onto main
git rebase origin/main

Step 5: Handle Result

On success or conflict, provide appropriate guidance.

Output Format

Successful Rebase

Rebasing feat/dark-mode onto main...

Rebased 3 commits:
  abc1234 Add theme toggle component
  def5678 Wire up theme context
  ghi9012 Add dark mode styles

New base: origin/main (xyz7890)

Your branch now has a clean, linear history!

Note: You'll need to force push to update remote:
  git push --force-with-lease

Or use: /git-push --force-with-lease

Already Up To Date

Branch feat/dark-mode is already based on latest main.

No rebase needed.

Rebase Conflicts

Conflict during rebase!

Currently rebasing commit: abc1234 Add theme toggle

Conflicting files:
  - src/components/Theme.tsx

To resolve:
  1. Edit the conflicting files
  2. git add <resolved-files>
  3. git rebase --continue

Or abort entirely:
  /git-abort
  (or: git rebase --abort)

Tip: Use /git-conflicts for guided resolution

Continue After Conflicts

To continue the rebase after resolving conflicts:

  git add <resolved-files>
  git rebase --continue

Remaining commits to rebase: 2

Current status:
  [x] abc1234 Add theme toggle (resolved)
  [ ] def5678 Wire up theme context
  [ ] ghi9012 Add dark mode styles

After Rebasing

Since rebase rewrites history, you need to force push:

# Safe force push (fails if remote changed)
git push --force-with-lease

# Regular force push (use carefully)
git push --force

Warning: Only force push if:

• You're the only one working on the branch
• You understand that remote history will be rewritten
• You've communicated with collaborators if any

Rebase vs Merge Comparison

Before (merge):
main:    A---B---C---F---G
              \     /
feature:       D---E

After merge, feature has merge commit.

Before (rebase):
main:    A---B---C
              \
feature:       D---E

After rebase:
main:    A---B---C
                  \
feature:           D'--E'

Rebase creates linear history (D and E rebased as D' and E').

Safety Tips

1. Never rebase shared branches: Only your personal feature branches
2. Use force-with-lease: Safer than --force
3. Have a backup: Know how to recover if needed
4. Test after rebase: Ensure everything still works

Integration

• Use /git-merge-main instead for shared branches
• Use /git-conflicts for conflict resolution help
• Use /git-abort to cancel a problematic rebase
• Use /git-push --force-with-lease after successful rebase