Ghost/.github/workflows/create-release-branch.yml

name: Create release branch
on:
  workflow_dispatch:
    inputs:
      base-ref:
        description: 'Git ref to base from (defaults to latest tag)'
        type: string
        default: 'latest'
        required: false
      bump-type:
        description: 'Version bump type (patch, minor)'
        type: string
        required: false
        default: 'patch'
env:
  FORCE_COLOR: 1
permissions:
  contents: write
jobs:
  create-branch:
    runs-on: ubuntu-latest
    steps:
      - run: echo "BASE_REF=main" >> $GITHUB_ENV
        if: inputs.base-ref == 'latest'

      - run: echo "BASE_REF=${{ inputs.base-ref }}" >> $GITHUB_ENV
        if: inputs.base-ref != 'latest'

      - uses: actions/checkout@v3
        with:
          ref: ${{ env.BASE_REF }}
          fetch-depth: 0
          submodules: true

      - name: Checkout most recent tag
        run: git checkout $(git describe --tags --abbrev=0)
        if: inputs.base-ref == 'latest'

      - uses: asdf-vm/actions/install@v2
        with:
          tool_versions: |
            semver 3.3.0            

      - run: |
          echo "CURRENT_SHA=$(git rev-parse HEAD)" >> $GITHUB_ENV
          echo "NEW_VERSION=$(semver bump ${{ inputs.bump-type }} $(git describe --tags --abbrev=0 --match=v*))" >> $GITHUB_ENV          

      - name: Create branch
        uses: actions/github-script@v6
        with:
          script: |
            const branchName = `v${process.env.NEW_VERSION}`;
            console.log(`Creating branch: ${branchName}`);
            await github.request('POST /repos/{owner}/{repo}/git/refs', {
              owner: context.repo.owner,
              repo: context.repo.repo,
              ref: `refs/heads/${branchName}`,
              sha: process.env.CURRENT_SHA
            });