name: merge-pr description: Script-first deterministic squash merge with strict required-check gating, head-SHA pinning, and reliable attribution/commenting.

Merge PR

Overview

Merge a prepared PR only after deterministic validation.

Inputs

• Ask for PR number or URL.
• If missing, use .local/prep.env from the PR worktree.

Safety

• Never use gh pr merge --auto in this flow.
• Never run git push directly.
• Require --match-head-commit during merge.
• Wrapper commands are cwd-agnostic; you can run them from repo root or inside the PR worktree.

Execution Contract

1. Validate merge readiness:

scripts/pr-merge verify <PR>

Backward-compatible verify form also works:

scripts/pr-merge <PR>

2. Run one-shot deterministic merge:

scripts/pr-merge run <PR>

3. Ensure output reports:

• merge_sha=<sha>
• merge_author_email=<email>
• comment_url=<url>

Steps

1. Validate artifacts

require=(.local/review.md .local/review.json .local/prep.md .local/prep.env)
for f in "${require[@]}"; do
  [ -s "$f" ] || { echo "Missing artifact: $f"; exit 1; }
done

2. Validate checks and branch status

scripts/pr-merge verify <PR>
source .local/prep.env

scripts/pr-merge treats “no required checks configured” as acceptable ([]), but fails on any required fail or pending.

3. Merge deterministically (wrapper-managed)

scripts/pr-merge run <PR>

scripts/pr-merge run performs:

• deterministic squash merge pinned to PREP_HEAD_SHA
• reviewer merge author email selection with fallback candidates
• one retry only when merge fails due to author-email validation
• co-author trailers for PR author and reviewer
• post-merge verification of both co-author trailers on commit message
• PR comment retry (3 attempts), then comment URL extraction
• cleanup after confirmed MERGED

4. Manual fallback (only if wrapper is unavailable)

scripts/pr merge-run <PR>

5. Cleanup

Cleanup is handled by run after merge success.

Guardrails

• End in MERGED, never CLOSED.
• Cleanup only after confirmed merge.