pull-labels.yml

name: Pull request labels

on:
  pull_request:
    types: [labeled, unlabeled, synchronize]

jobs:
  version-labels:
    name: 'check version label'
    runs-on: ubuntu-18.04

    steps:
    - name: Check if version label is present
      uses: actions/github-script@0.4.0
      with:
        github-token: ${{ secrets.GITHUB_TOKEN }}
        script: |
          const versionLabels = [
            'Action: no bump',
            'Action: beta bump',
            'Action: patch bump',
            'Action: minor bump',
            'Action: major bump',
          ];

          const { data: labels } = await github.issues.listLabelsOnIssue({
            owner: context.repo.owner,
            repo: context.repo.repo,
            issue_number: context.payload.pull_request.number,
            per_page: 100,
          });

          const versionLabelsPresent = labels
            .filter(label => versionLabels.includes(label.name))

          if (versionLabelsPresent.length === 1) {
            return;
          }

          console.log(`::debug ::${versionLabelsPresent.length} matching labels`);

          throw new Error(`Should have one and only one of ${versionLabels.join(', ')} labels`);