Enable Pull Request Auto-merge

A GitHub action to enable auto-merge on a pull request.

⚠️ There are very specific conditions under which this action will work. See Conditions for details.

Usage

      - uses: peter-evans/enable-pull-request-automerge@v2
        with:
          token: ${{ secrets.PAT }}
          pull-request-number: 1

Action inputs

Name	Description	Default
token	GITHUB_TOKEN (permissions pull_requests: write, contents: write) or a repo scoped Personal Access Token (PAT).	GITHUB_TOKEN
repository	The target GitHub repository containing the pull request.	github.repository (Current repository)
pull-request-number	(required) The number of the target pull request
merge-method	The merge method to use. merge, rebase or squash.	merge

Conditions

This action uses a GitHub API that only works under specific conditions. All of the following conditions must be true for this action to succeed.

1. The target repository must have Allow auto-merge enabled in settings.
2. The pull request base must have a branch protection rule with at least one requirement enabled.
3. The pull request must be in a state where requirements have not yet been satisfied. If the pull request can already be merged, attempting to enable auto-merge will fail.

Dependabot example

The following example will automerge dependabot pull requests. Note that if you use the default GITHUB_TOKEN, as in the example, the merge will not trigger further workflow runs. If you want to trigger further workflow runs, you will need to use a repo scoped Personal Access Token (PAT).

name: Auto-merge Dependabot
on: pull_request

permissions:
  pull-requests: write
  contents: write

jobs:
  automerge:
    runs-on: ubuntu-latest
    if: github.actor == 'dependabot[bot]'
    steps:
      - uses: peter-evans/enable-pull-request-automerge@v2
        with:
          pull-request-number: ${{ github.event.pull_request.number }}
          merge-method: squash

Create pull request example

In the following example create-pull-request action is used to create a pull request containing some changes that we want to merge automatically once requirements have been satisfied.

      - uses: actions/checkout@v3

      # Make changes to pull request here

      - name: Create Pull Request
        id: cpr
        uses: peter-evans/create-pull-request@v3
        with:
          token: ${{ secrets.PAT }}

      - name: Enable Pull Request Automerge
        if: steps.cpr.outputs.pull-request-operation == 'created'
        uses: peter-evans/enable-pull-request-automerge@v2
        with:
          token: ${{ secrets.PAT }}
          pull-request-number: ${{ steps.cpr.outputs.pull-request-number }}
          merge-method: squash

If the "require pull request reviews" branch protection has been enabled we can optionally auto-approve the pull request by adding the following step to the example above. The if condition makes sure we don't approve multiple times if the workflow executes more than once before the pull request merges.

      - name: Auto approve
        if: steps.cpr.outputs.pull-request-operation == 'created'
        uses: juliangruber/approve-pull-request-action@v2
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          number: ${{ steps.cpr.outputs.pull-request-number }}

License

MIT