vercel__workflow/.github/actions/detect-ci-scope/action.yml

name: 'Detect CI Scope'
description: 'Classify pull request changes for runtime and validation CI fast paths.'

inputs:
  github-token:
    description: 'Token used to list changed pull request files.'
    required: true

outputs:
  runtime-fast-path:
    description: 'Whether expensive runtime E2E and benchmark lanes may be skipped.'
    value: ${{ steps.scope.outputs.runtime-fast-path }}
  validation-fast-path:
    description: 'Whether all package validation lanes may be skipped.'
    value: ${{ steps.scope.outputs.validation-fast-path }}

runs:
  using: 'composite'
  steps:
    - name: Classify changed files
      id: scope
      uses: actions/github-script@v7
      with:
        github-token: ${{ inputs.github-token }}
        script: |
          if (context.eventName !== 'pull_request') {
            core.setOutput('runtime-fast-path', 'false');
            core.setOutput('validation-fast-path', 'false');
            return;
          }

          const files = await github.paginate(github.rest.pulls.listFiles, {
            owner: context.repo.owner,
            repo: context.repo.repo,
            pull_number: context.issue.number,
            per_page: 100,
          });
          const validationFastPathPatterns = [
            /^\.changeset\/[^/]+\.md$/,
            /^docs\//,
            /^(AGENTS|CONTRIBUTING|LICENSE|README)\.md$/,
            /^packages\/[^/]+\/README\.md$/,
          ];
          const runtimeFastPathPatterns = [
            ...validationFastPathPatterns,
            /^packages\/web\//,
            /^packages\/web-shared\//,
          ];
          const changedFiles = files.map((file) => file.filename);
          const runtimeFiles = changedFiles.filter(
            (filename) =>
              !runtimeFastPathPatterns.some((pattern) => pattern.test(filename))
          );
          const validationFiles = changedFiles.filter(
            (filename) =>
              !validationFastPathPatterns.some((pattern) => pattern.test(filename))
          );
          const runtimeFastPath = runtimeFiles.length === 0;
          const validationFastPath = validationFiles.length === 0;

          core.setOutput('runtime-fast-path', runtimeFastPath ? 'true' : 'false');
          core.setOutput('validation-fast-path', validationFastPath ? 'true' : 'false');
          core.info(
            runtimeFastPath
              ? 'Only docs or UI files changed; runtime E2E and benchmarks may be skipped.'
              : `Runtime CI required by: ${runtimeFiles.join(', ')}`
          );
          core.info(
            validationFastPath
              ? 'Only inert documentation files changed; package validation may be skipped.'
              : `Package validation required by: ${validationFiles.join(', ')}`
          );