create-or-update-pr

name	create-or-update-pr
description	Creates or updates the GitHub Pull Request for the current branch, generating title and body from git log and diff.

Your task is to create or update the GitHub Pull Request for the current branch.

Steps

1. Run these commands in parallel to gather context:

   • git log --oneline $(git merge-base HEAD master)..HEAD — commits on this branch
   • git diff $(git merge-base HEAD master)..HEAD --stat — changed files summary
   • gh pr view --json number,title,body,state 2>/dev/null — existing PR, if any

2. Analyze all commits and changed files to understand the intent of the branch.

3. Build the PR title:

   • Follow conventional commits: type(scope): short description
   • Use the most significant type across all commits (feat > fix > refactor > chore)
   • If there is only one commit and its message is already a good title, use it directly
   • Keep it under 72 characters
   • Do not add a period at the end

4. Build the PR body using this template:

## Summary
- <bullet 1>
- <bullet 2>

## Changes
- <file or area>: <what changed and why>

## Test plan
- [ ] <step to verify>

• Summary: 2–4 bullets on what and why, not how
• Changes: one line per meaningful file group or area changed
• Test plan: concrete steps a reviewer can follow to verify the PR

5. If no PR exists for this branch, create one targeting master:

gh pr create --title "..." --body "$(cat <<'EOF'
...
EOF
)"

6. If a PR already exists, update its title and body:

gh pr edit --title "..." --body "$(cat <<'EOF'
...
EOF
)"

7. Output the PR URL at the end.

Rules

• Never push commits — only create or edit the PR metadata
• If the branch has no commits ahead of master, tell the user and stop
• Use the gh CLI for all GitHub operations
• Always use a HEREDOC (<<'EOF') to pass the body so newlines are preserved