vrt.yml

name: Visual regression testing

on:
    push:
      branches:
        - main
    pull_request:
      # the closed event type gives us the head_ref (the name of the branch being merged into main)
      types:
        - closed
      # for PRs merging into the below branches
      branches:
        - main
        - spectrum_two
        - s2-foundations-redux
    workflow_dispatch:
    workflow_call:
        inputs:
            skip:
                description: "Skip running VRT"
                required: false
                type: boolean
                default: false
        outputs:
            storybook-url:
                description: "URL of the published Storybook"
                value: ${{ jobs.vrt.outputs.storybook-url }}

permissions:
    contents: read
    pull-requests: write

jobs:
    vrt:
        # if the branch being merged is a dependabot branch or a changeset release, skip everything in this workflow
        if: ${{!startsWith(github.head_ref, 'dependabot') && !startsWith(github.head_ref, 'changeset-release') }}
        name: Chromatic
        runs-on: ubuntu-latest
        timeout-minutes: 20
        outputs:
          storybook-url: ${{ steps.chromatic.outputs.storybookUrl != 'undefined' && steps.chromatic.outputs.storybookUrl || '' }}
        steps:
            - name: Check out code
              uses: actions/checkout@v4
              with:
                  fetch-depth: 0

            - name: Use Node LTS version
              uses: actions/setup-node@v4
              with:
                  node-version: 20
                  cache: yarn

            - name: Enable Corepack
              run: corepack enable

            ## --- YARN CACHE --- ##
            - name: Check for cached dependencies
              continue-on-error: true
              id: cache-dependencies
              uses: actions/cache@v4
              with:
                  path: |
                      .cache/yarn
                      node_modules
                  key: ubuntu-latest-node20-${{ hashFiles('yarn.lock') }}

            ## --- INSTALL --- ##
            - name: Install dependencies
              shell: bash
              run: yarn install --immutable

            - name: Publish to Chromatic
              id: chromatic
              uses: chromaui/action@latest
              with:
                  projectToken: ${{ secrets.CHROMATIC_PROJECT_TOKEN }}
                  buildScriptName: ci:storybook
                  storybookConfigDir: .storybook
                  storybookBaseDir: .storybook
                  exitOnceUploaded: true
                  onlyChanged: true
                  traceChanged: true
                  untraced: ".github/actions/*/package.json site/package.json generator/package.json"
                  diagnostics: true
                  autoAcceptChanges: "main"
                  # Lets VRT pass without running so as not to waste snapshots
                  skip: ${{ inputs.skip }}