Function runVisualTests

build-system/tasks/visual-diff/index.js:253–338

* Sets the AMP config, launches a server, and generates Percy snapshots for a * set of given webpages. * * @param {!puppeteer.Browser} browser a Puppeteer controlled browser. * @param {!Array<!WebpageDef>} webpages details about the pages to snapshot. * @return {Promise }

(browser, webpages)

 * @return {Promise<void>}
 */
async function runVisualTests(browser, webpages) {
  const numUnfilteredPages = webpages.length;
  webpages = webpages.filter((webpage) => !webpage.flaky);
  if (numUnfilteredPages != webpages.length) {
    log(
      'info',
      'Skipping',
      cyan(numUnfilteredPages - webpages.length),
      'flaky pages'
    );
  }
  if (argv.grep) {
    webpages = webpages.filter((webpage) => argv.grep.test(webpage.name));
    log(
      'info',
      cyan(`--grep ${argv.grep}`),
      'matched',
      cyan(webpages.length),
      'pages'
    );
  }

  // Expand all the interactive tests. Every test should have a base test with
  // no interactions, and each test that has in interactive tests file should
  // load those tests here.
  for (const webpage of webpages) {
    webpage.tests_ = {};
    if (!webpage.no_base_test) {
      webpage.tests_[''] = BASE_TEST_FUNCTION;
    }
    if (webpage.interactive_tests) {
      try {
        Object.assign(
          webpage.tests_,
          require(path.resolve(ROOT_DIR, webpage.interactive_tests))
        );
      } catch (error) {
        log(
          'fatal',
          'Failed to load interactive test',
          cyan(webpage.interactive_tests),
          'for test',
          cyan(webpage.name),
          '\nError:',
          error
        );
      }
    }
  }

  const totalTests = webpages.reduce(
    (numTests, webpage) => numTests + Object.keys(webpage.tests_).length,
    0
  );
  if (!totalTests) {
    log('fatal', 'No pages left to test!');
  } else {
    log(