Smart Merge

Smart Merge

Merges branches with pre-merge validation while preserving your feature branch.

Two Merge Modes

Feature branch is never deleted. You stay on (or return to) your working branch after every operation.

Package Manager Detection

Detect the project's package manager before running validation. The script checks in priority order: pnpm-lock.yaml wins over any other lock file, so projects with multiple lock files default to pnpm.

# Auto-detect package manager (pnpm wins on ties)
if [ -f pnpm-lock.yaml ]; then PM="pnpm"
elif [ -f yarn.lock ]; then PM="yarn"
elif [ -f package-lock.json ]; then PM="npm run"
elif [ -f go.mod ]; then PM="go"
elif [ -f pyproject.toml ] || [ -f requirements.txt ]; then PM="python"
else PM="pnpm"; fi

Pre-Merge Validation

Run these checks before every merge. Stop and report failures instead of proceeding.

If any check fails, stop the merge and report which check failed with the full error output.

Mode 1: Sync (main -> feature)

Bring main into your feature branch. Run regularly to catch conflicts early.

Steps:

1. Save current branch: FEATURE_BRANCH=$(git branch --show-current)
2. Fetch latest: git fetch origin
3. Run pre-merge validation (all checks above except CI and comments)
4. Merge main into feature: git merge origin/main
5. If conflicts occur, resolve them (see Conflict Resolution below)
6. Run validation again after merge completes
7. Verify you are still on $FEATURE_BRANCH: git branch --show-current

Conflict Resolution:

1. List conflicted files: git diff --name-only --diff-filter=U
2. Resolve each file
3. Stage resolved files: git add <file> (stage each file by name, not git add .)
4. Complete merge: git commit
5. Re-run validation

Rebase alternative (linear history):

Use rebase only on local/personal branches, never on shared branches.

git fetch origin
git rebase origin/main
# On conflicts: resolve, then git rebase --continue
git push --force-with-lease

Mode 2: PR Merge (feature -> main)

Merge your PR after approval. Confirm with the user before executing the merge.

Steps:

1. Save current branch: FEATURE_BRANCH=$(git branch --show-current)
2. Get PR number: PR=$(gh pr view --json number -q '.number')
3. Check for unreplied review comments (see below). If any exist, stop and report them.
4. Run full pre-merge validation (all checks including CI)
5. Show PR summary to user:

   gh pr view $PR --json title,commits,changedFiles --jq '
     "Title: \(.title)\nCommits: \(.commits | length)\nFiles changed: \(.changedFiles)"
   '
   

6. Ask the user to confirm before proceeding
7. Pick merge strategy. Default to --merge. Use --squash if the repo enforces squash merges, --rebase if it enforces linear history. Check repo policy: gh repo view --json mergeCommitAllowed,squashMergeAllowed,rebaseMergeAllowed
8. Execute merge (do not use --delete-branch):

   gh pr merge $PR --merge --body "$(cat <<'EOF'
   - Key change 1
   - Key change 2
   
   Tests: passed
   Reviews: addressed
   EOF
   )"
   

9. Return to feature branch: git checkout "$FEATURE_BRANCH"

Check unreplied review comments:

PR=$(gh pr view --json number -q '.number')
REPO=$(gh repo view --json nameWithOwner -q '.nameWithOwner')

UNREPLIED=$(gh api repos/$REPO/pulls/$PR/comments --jq '
  [.[] | select(.in_reply_to_id) | .in_reply_to_id] as $replied |
  [.[] | select(.in_reply_to_id == null) | select(.id | IN($replied[]) | not)]
  | length
' 2>/dev/null) || {
  echo "Warning: Could not fetch comments. Verify manually."
  UNREPLIED=0
}

if [ "$UNREPLIED" -gt 0 ]; then
  echo "Blocked: $UNREPLIED unreplied comments. Address them before merging."
  exit 1
fi

Post-Merge Verification

Run this checklist after every merge operation:

Post-Merge Checklist:
- [ ] On correct branch: git branch --show-current
- [ ] Clean working tree: git status
- [ ] Merge visible in history: git log --oneline -5
- [ ] Validation passes: $PM test && $PM lint && $PM typecheck

If any check fails, see Error Recovery below.

Merge Message Format

Keep merge messages under 10 lines:

- Key change 1 (what was added/fixed)
- Key change 2
- Key change 3

Tests: X passed
Reviews: N/N addressed
Refs: #123, PROJ-456

Rules

Branch Preservation

To delete a branch after merge (only when the user explicitly requests it):

git branch -d feature/my-branch           # local
git push origin --delete feature/my-branch # remote

Error Recovery

Merge failed mid-way:

git merge --abort  # Cancel incomplete merge
git status         # Verify clean state

On wrong branch after merge:

git checkout "$FEATURE_BRANCH"

Undo a completed merge:

git reflog                  # Find the commit before the merge
git reset --hard <sha>      # Reset to that commit

User: "Sync my branch with main"

1. Detected pnpm from pnpm-lock.yaml
2. Ran pnpm test && pnpm lint && pnpm typecheck -- all passed
3. Ran git fetch origin && git merge origin/main -- fast-forward merge
4. Ran validation again -- all passed
5. Confirmed on branch feature/auth-flow

Result: Branch synced, 0 conflicts, all checks green.

User: "Update my feature branch from main"

1. Detected npm from package-lock.json
2. Ran npm run test && npm run lint -- passed
3. Ran git fetch origin && git merge origin/main -- 2 conflicts in src/api.ts and src/config.ts
4. Listed conflicts: git diff --name-only --diff-filter=U
5. Resolved both files, staged with git add src/api.ts src/config.ts
6. Completed merge: git commit
7. Ran validation again -- passed
8. Confirmed on branch feature/new-api

Result: Branch synced, 2 conflicts resolved, all checks green.

User: "Merge my PR"

1. Detected pnpm, ran full validation -- all passed
2. Checked unreplied comments -- 0 unreplied
3. Verified CI: gh pr checks 47 -- all green
4. Showed summary: "Title: Add auth module | Commits: 3 | Files changed: 7"
5. User confirmed
6. Ran gh pr merge 47 --merge (no --delete-branch)
7. Returned to feature/auth-module with git checkout

Result: PR #47 merged, feature branch preserved, back on working branch.

User: "Merge my PR into main"

1. Detected pnpm, ran validation -- all passed
2. Checked unreplied comments -- found 2 unreplied
3. Stopped. Reported: "Blocked: 2 unreplied review comments on PR #32. Address them before merging."

Result: Merge blocked. User needs to reply to review comments first.