build: add retry mechanism for test file import

ci/postinstall.mts

@@ -0,0 +1,50 @@
+import { execSync } from 'child_process';
+import { readFileSync, writeFileSync } from 'fs';
+
+const root = new URL('..', import.meta.url);
+
+main();
+
+function main() {
+  exec('yarn playwright install --with-deps');
+
+  new Map<string, [string, string]>()
+    .set('node_modules/@web/test-runner-mocha/dist/autorun.js', [
+      'await import(new URL(r,f).href)',
+      'await import(new URL(r,f).href)' +
+        '.catch(()=>{console.warn(`Failed to load test file ${r}. Retrying...`);return new Promise(r=>setTimeout(r, 100)).then(()=>import(new URL(r,f).href))})'.repeat(3),
+    ])
+    .forEach(([search, replace], filePath) => searchAndReplace(search, replace, filePath));
+}
+
+/**
+ * Schedules an edit where the specified file is read and its content replaced based on
+ * the given search expression and corresponding replacement. Throws if no changes were made
+ * and the patch has not been applied.
+ */
+function searchAndReplace(search: string, replacement: string, relativeFilePath: string) {
+  const filePath = new URL(relativeFilePath, root);
+  const originalContent = readFileSync(filePath, 'utf8');
+  const newFileContent = originalContent.replace(search, replacement);
+  if (originalContent === newFileContent) {
+    throw Error(`Could not perform replacement in: ${filePath}.\nSearched for pattern: ${search}`);
+  }
+  writeFileSync(filePath, newFileContent, 'utf8');
+}
+
+/**
+ * Executes the given command in the project directory.
+ * @param command The command to run
+ * @param captureStdout Whether the stdout should be captured and
+ *   returned.
+ */
+function exec(command: string, captureStdout = false) {
+  const stdout = execSync(command, {
+    cwd: root,
+    stdio: ['inherit', captureStdout ? 'pipe' : 'inherit', 'inherit'],
+  });
+  if (captureStdout) {
+    process.stdout.write(stdout);
+    return stdout.toString().trim();
+  }
+}

package.json

@@ -28,7 +28,7 @@
     "src/global/**/*.scss"
   ],
   "scripts": {
-    "postinstall": "yarn playwright install --with-deps",
+    "postinstall": "tsx ci/postinstall.mts",
     "build:components": "vite build",
     "build:storybook": "storybook build --quiet",
     "build:chromatic-stories": "tsx ci/chromatic-stories-generator.ts",

web-test-runner.config.js

@@ -26,9 +26,9 @@ const e2eFiles = glob
 
 const browsers = isCIEnvironment
   ? [
-      playwrightLauncher({ product: 'chromium', concurrency: 1 }),
-      playwrightLauncher({ product: 'firefox', concurrency: 1 }),
-      playwrightLauncher({ product: 'webkit', concurrency: 1 }),
+      playwrightLauncher({ product: 'chromium' }),
+      playwrightLauncher({ product: 'firefox' }),
+      playwrightLauncher({ product: 'webkit' }),
     ]
   : isDebugMode
   ? [puppeteerLauncher({ concurrency: 1, launchOptions: { headless: false, devtools: true } })]