feat(ui): make JS asset load error message translatable (#7388)

- The 'Failed to load asset files from [...]' is now an translatable string.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7388
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: 0ko <0ko@noreply.codeberg.org>
Co-committed-by: 0ko <0ko@noreply.codeberg.org>

tests/integration/common_navigation_test.go

@@ -0,0 +1,41 @@
+// Copyright 2024-2025 The Forgejo Authors. All rights reserved.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package integration
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+	"testing"
+
+	"forgejo.org/models/unittest"
+	"forgejo.org/modules/translation"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// This test verifies common elements that are visible on all pages but most
+// likely to be first seen on `/`
+func TestCommonNavigationElements(t *testing.T) {
+	require.NoError(t, unittest.PrepareTestDatabase())
+
+	session := loginUser(t, "user1")
+	locale := translation.NewLocale("en-US")
+
+	response := session.MakeRequest(t, NewRequest(t, "GET", "/"), http.StatusOK)
+	page := NewHTMLParser(t, response.Body)
+
+	// Navbar
+	links := page.Find("#navbar .dropdown[data-tooltip-content='Create…'] .menu")
+	assert.Equal(t, locale.TrString("new_repo.link"), strings.TrimSpace(links.Find("a[href='/repo/create']").Text()))
+	assert.Equal(t, locale.TrString("new_migrate.link"), strings.TrimSpace(links.Find("a[href='/repo/migrate']").Text()))
+	assert.Equal(t, locale.TrString("new_org.link"), strings.TrimSpace(links.Find("a[href='/org/create']").Text()))
+
+	// After footer: index.js
+	page.AssertElement(t, "script[src^='/assets/js/index.js']", true)
+	onerror, _ := page.Find("script[src^='/assets/js/index.js']").Attr("onerror")
+	expected := fmt.Sprintf("alert('%s'.replace('{path}', this.src))", locale.TrString("alert.asset_load_failed"))
+	assert.Equal(t, expected, onerror)
+}