Checkout Merge

This action synthesizes the merge commit GitHub would give you via refs/pull/X/merge.

With GitHub.com's current implementation as of Dec 8, 2021, if it was able to make a merge commit, and then a push causes the current state to be not mergable, the refs/pull/X/merge ref may stick around resulting in confusing output.

With this action, instead, you will not get a merge commit.

If you use @actions/checkout to try to check out refs/pull/X/merge and it doesn't exist, the action will make three attempts (failing each time), and then leave your workflow in a failed state and your user with a fairly confusing log.

If you instead use @actions/checkout to check out the base commit, then you can use this action to get a merge commit. If it isn't able to, it can produce an error message that is hopefully easier for users to understand, and allow you to decide whether your workflow should ✅ or ❌.

Usage

    - name: checkout
      uses: actions/checkout@v3
    - name: checkout-merge
      if: "contains(github.event_name, 'pull_request')"
      uses: check-spelling/checkout-merge@main
      with:
        # Base for merge (it will be checked out)
        # Default: ${{ github.event.pull_request.base.sha }}
        base_ref: ''

        # Head for merge (it will be fetched and merged)
        # Default: ${{ github.event.pull_request.head.sha }}
        head_ref: ''

        # Relative path under $GITHUB_WORKSPACE to the repository
        # Default: .
        path: ''

        # Suppress reporting errors (consumers would report the message themselves)
        # By default, this action reports errors in the workflow overview.
        # If you want to handle reporting the error in some other manner,
        # you can set this flag.
        # Default: false
        do_not_report: ''
    - if: env.MERGE_FAILED != '1'
      run: ...

Outputs

• message - Message describing what prevented the action from producing a merge commit.

• status - success or failed

Environment products

• $MERGE_FAILED will be set to 1 if a merge can't be created.