Fix relative-time RangeError in headless browsers

Add 'en' fallback for navigator.language which can be undefined in
headless browsers (e.g. Playwright Firefox), causing RangeError in
Intl.DateTimeFormat. Add e2e test and shared assertNoJsError helper.

Co-Authored-By: Claude (Opus 4.6) <noreply@anthropic.com>

Author: silverwind

modules/setting/setting.go

@@ -31,6 +31,10 @@ var (
 	// IsInTesting indicates whether the testing is running. A lot of unreliable code causes a lot of nonsense error logs during testing
 	// TODO: this is only a temporary solution, we should make the test code more reliable
 	IsInTesting = false
+
+	// IsE2ETest indicates whether the server is running for e2e tests, set via GITEA_E2E_TEST env var.
+	// IsInTesting is unsuitable because it has many side effects for in-process unit/integration tests.
+	IsE2ETest = os.Getenv("GITEA_E2E_TEST") == "true"
 )
 
 func init() {

routers/web/web.go

@@ -1740,7 +1740,7 @@ func registerWebRoutes(m *web.Router, webAuth *AuthMiddleware) {
 		m.Get("/swagger.v1.json", SwaggerV1Json)
 	}
 
-	if !setting.IsProd {
+	if !setting.IsProd || setting.IsE2ETest {
 		m.Group("/devtest", func() {
 			m.Any("", devtest.List)
 			m.Any("/fetch-action-test", devtest.FetchActionTest)

templates/devtest/relative-time.tmpl

@@ -3,7 +3,7 @@
 	<div class="tw-grid tw-grid-cols-3 tw-gap-4">
 		<div>
 			<h2>Relative (auto)</h2>
-			<div>now: <relative-time datetime="{{.TimeNow.Format "2006-01-02T15:04:05Z07:00"}}"></relative-time></div>
+			<div>now: <relative-time data-testid="relative-time-now" datetime="{{.TimeNow.Format "2006-01-02T15:04:05Z07:00"}}"></relative-time></div>
 			<div>3m ago: <relative-time datetime="{{.TimePast3m.Format "2006-01-02T15:04:05Z07:00"}}"></relative-time></div>
 			<div>3h ago: <relative-time datetime="{{.TimePast3h.Format "2006-01-02T15:04:05Z07:00"}}"></relative-time></div>
 			<div>1d ago: <relative-time datetime="{{.TimePast1d.Format "2006-01-02T15:04:05Z07:00"}}"></relative-time></div>

tests/e2e/relative-time.test.ts

@@ -0,0 +1,10 @@
+import {test, expect} from '@playwright/test';
+import {assertNoJsError} from './utils.ts';
+
+test('relative-time renders without errors', async ({page}) => {
+  await page.goto('/devtest/relative-time');
+  const relativeTime = page.getByTestId('relative-time-now');
+  await expect(relativeTime).toHaveAttribute('data-tooltip-content', /.+/);
+  await expect(relativeTime).toHaveText('now');
+  await assertNoJsError(page);
+});

tests/e2e/utils.ts

@@ -104,6 +104,10 @@ export async function login(page: Page, username = env.GITEA_TEST_E2E_USER, pass
   await expect(page.getByRole('link', {name: 'Sign In'})).toBeHidden();
 }
 
+export async function assertNoJsError(page: Page) {
+  await expect(page.locator('.js-global-error')).toHaveCount(0);
+}
+
 export async function logout(page: Page) {
   await page.context().clearCookies(); // workaround issues related to fomantic dropdown
   await page.goto('/');

tools/test-e2e.sh

@@ -43,6 +43,7 @@ LEVEL = Warn
 EOF
 
 export GITEA_WORK_DIR="$WORK_DIR"
+export GITEA_E2E_TEST=true
 
 # Start Gitea server
 echo "Starting Gitea server on port $FREE_PORT (workdir: $WORK_DIR)..."

web_src/js/webcomponents/relative-time.ts

@@ -259,12 +259,12 @@ class RelativeTime extends HTMLElement {
 
   get #lang(): string {
     const lang = this.closest('[lang]')?.getAttribute('lang');
-    if (!lang) return navigator.language;
-    try {
-      return new Intl.Locale(lang).toString();
-    } catch {
-      return navigator.language;
+    if (lang) {
+      try {
+        return new Intl.Locale(lang).toString();
+      } catch { /* invalid locale, fall through */ }
     }
+    return navigator.language ?? 'en';
   }
 
   get second(): 'numeric' | '2-digit' | undefined {