How to Use Automatic Rebase with GitHub Action

name: Automatic Rebase
on:
  issue_comment:
    types: [created]

jobs:
  rebase:
    name: Rebase
    runs-on: ubuntu-latest
    if: >
      github.event.issue.pull_request != '' &&
      (
        contains(github.event.comment.body, '/rebase') || 
        contains(github.event.comment.body, '/autosquash')
      )
    steps:
      - name: Checkout the latest code
        uses: actions/checkout@v3
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          fetch-depth: 0

      - name: Automatic Rebase
        uses: cirrus-actions/[email protected]
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Automatic Rebase

GitHub Action to automatically rebase pull requests when triggered by a comment.

What is Automatic Rebase GitHub Action?​

This GitHub Action automatically rebases pull requests when a comment triggers it. It can simplify your workflow by ensuring PRs are up-to-date without manual intervention. Supports /rebase and /autosquash commands to trigger the action.

How to Trigger a Rebase​

Once the action is configured, simply comment /rebase or /autosquash on a pull request to trigger the rebase.

Example:

/rebase

How to Handle Autosquash​

You can trigger an autosquash by commenting /autosquash or /rebase-autosquash on the PR. The action will handle rebasing and squashing the commits automatically.

with:
  autosquash: ${{ contains(github.event.comment.body, '/autosquash') || contains(github.event.comment.body, '/rebase-autosquash') }}

How to Use Personal Access Token (PAT)​

To ensure GitHub Actions re-run after a successful rebase, use a Personal Access Token (PAT) instead of the default GITHUB_TOKEN:

- name: Checkout the latest code
  uses: actions/checkout@v3
  with:
    token: ${{ secrets.PAT_TOKEN }}
    fetch-depth: 0

- name: Automatic Rebase
  uses: cirrus-actions/[email protected]
  env:
    GITHUB_TOKEN: ${{ secrets.PAT_TOKEN }}

How to Rebase a Specific PR​

You can specify the pull request number in the workflow if it isn't directly referred to by the action:

- name: Automatic Rebase
  uses: cirrus-actions/[email protected]
  env:
    GITHUB_TOKEN: ${{ secrets.PAT_TOKEN }}
    PR_NUMBER: 1245

Restricting Who Can Call the Action​

You can restrict who can trigger the rebase by checking the author_association field in the comment:

if: github.event.comment.author_association == 'MEMBER'

This ensures that only certain users, such as repository members, can call the action.

Handling Review Dismissals After Rebase​

To automatically dismiss existing reviews after a rebase and require re-approval, enable this setting in GitHub:

• Go to Settings > Branches > Branch protection rules > Require pull request reviews before merging.
• Check the option Dismiss stale pull request approvals when new commits are pushed.

This will ensure reviews are dismissed after a successful rebase and will require re-approval before merging.