GitHub PR Cleanup

Clean up local git state after a PR is merged, and handle cherry-pick instructions if present in the PR body.

Input

The user provides a GitHub PR URL (e.g., https://github.com/erigontech/erigon/pull/19785). Extract the repo owner/name and PR number from it.

Step 1: Check PR Status

gh pr view <number> --repo <owner>/<repo> --json state,mergedAt,mergeCommit,headRefName,baseRefName,title,body,number

If the PR is not in the MERGED state, tell the user "PR # is not merged yet" and stop — do nothing else.

Step 2: Identify the Local Worktree

The PR's headRefName is the branch used for the PR. Find the local worktree that tracks this branch:

git worktree list --porcelain

Parse the porcelain output to find the worktree whose branch field matches refs/heads/<headRefName>. If no matching worktree is found, skip worktree removal and tell the user (the branch may still exist without a worktree).

Step 3: Remove the Worktree

If a matching worktree was found, remove it:

git worktree remove <worktree-path>

If it fails due to uncommitted changes, add --force and warn the user that uncommitted work was discarded.

Report the removed worktree path to the user.

Step 4: Remove the Local Branch

Delete the local branch that the PR used:

git branch -D <headRefName>

Report the deleted branch name.

Step 5: Fetch the Target Branch and Find the Squash Commit

The PR's baseRefName is the branch the PR was merged into (e.g., main). The mergeCommit.oid from the gh pr view output is the squash commit SHA.

Fetch the target branch to make sure we have the latest:

git fetch origin <baseRefName>

YubiKey note: This triggers an SSH operation — remind the user to press their YubiKey.

Verify the squash commit exists locally:

git cat-file -t <mergeCommit.oid>

Report the squash commit SHA and its one-line summary to the user.

Step 6: Check for Cherry-Pick Instructions

Parse the PR body for cherry-pick instructions. Look for lines matching patterns like:

• - [ ] Cherry-pick merge commit to <target>
• - [ ] Cherry-pick to <target>
• - [x] Cherry-pick merge commit to <target> (already done — skip)

The target is typically a branch name in backticks, e.g., `release/3.4`.

If no cherry-pick instruction is found, or if all cherry-pick items are already checked ([x]), report that there's nothing more to do and stop.

If an unchecked cherry-pick instruction is found, proceed to Step 7.

Step 7: Cherry-Pick to Target Branch

Given:

• squash_commit = the merge commit SHA from Step 5
• cherry_pick_target = the branch extracted from the cherry-pick instruction (e.g., release/3.4)
• pr_number = the original PR number
• pr_title = the original PR title

7a: Fetch the cherry-pick target branch

git fetch origin <cherry_pick_target>

YubiKey note: Remind the user to press their YubiKey.

7b: Create an ephemeral branch

The branch name format is cherry-pick-PR<number>-to-<target-branch-name> where slashes in the target are replaced with dashes:

# Example: cherry-pick-PR19785-to-release-3.4
git checkout -b cherry-pick-PR<number>-to-<sanitized-target> origin/<cherry_pick_target>

7c: Cherry-pick the squash commit

git cherry-pick <squash_commit>

If the cherry-pick has conflicts, stop and tell the user — do not attempt to resolve conflicts automatically.

7d: Push the ephemeral branch

git push -u origin cherry-pick-PR<number>-to-<sanitized-target>

YubiKey note: Remind the user to press their YubiKey.

7e: Create the cherry-pick PR

The PR title format prepends [cherry-pick] and the release tag to the original title.

For example, if the target is release/3.4 and the original title is snapcfg: load preverified hashes for single chain only, the cherry-pick PR title becomes: [cherry-pick] [r3.4] snapcfg: load preverified hashes for single chain only

The [rX.Y] tag is derived from the target branch name by stripping the release/ prefix.

gh pr create \
  --base <cherry_pick_target> \
  --head cherry-pick-PR<number>-to-<sanitized-target> \
  --title "[cherry-pick] [r<version>] <original-title>" \
  --body "$(cat <<'EOF'
Cherry-pick of #<pr_number> (<squash_commit_short>) to <cherry_pick_target>.
EOF
)"

Report the new PR URL to the user.

7f: Update the original PR

Mark the cherry-pick task as done in the original PR body and reference the new cherry-pick PR. Use gh pr edit to update the body — replace the unchecked cherry-pick item:

- [ ] Cherry-pick merge commit to `release/3.4`

with a checked item referencing the new PR:

- [x] Cherry-pick merge commit to `release/3.4` — #<cherry-pick-pr-number>

gh pr edit <original_pr_number> --repo <owner>/<repo> --body "<updated-body>"

7g: Clean up the ephemeral branch locally

Switch back to the main worktree's branch and delete the ephemeral branch:

git checkout <previous-branch>
git branch -D cherry-pick-PR<number>-to-<sanitized-target>

Summary

At the end, print a summary of everything that was done:

• Worktree removed: <path> (or "no worktree found")
• Branch deleted: <headRefName>
• Squash commit: <short-sha> <one-line-summary>
• Cherry-pick PR created: <url> (or "no cherry-pick needed")
• Original PR updated: yes/no