Initial commit of 001code-html Scratch frontend project.

Includes scratch-gui, scratch-vm, scratch-blocks, scratch-render, scratch-l10n, and deployment config.

Co-authored-by: Cursor <cursoragent@cursor.com>

scratch-gui/test/unit/util/detect-locale.test.js

@@ -0,0 +1,86 @@
+import {detectLocale} from '../../../src/lib/detect-locale.js';
+
+const supportedLocales = ['en', 'es', 'pt-br', 'de', 'it'];
+
+Object.defineProperty(window.location,
+    'search',
+    {value: '?name=val', configurable: true}
+);
+Object.defineProperty(window.navigator,
+    'language',
+    {value: 'en-US', configurable: true}
+);
+
+describe('detectLocale', () => {
+    test('uses locale from the URL when present', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?locale=pt-br'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('pt-br');
+    });
+
+    test('is case insensitive', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?locale=pt-BR'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('pt-br');
+    });
+
+    test('also accepts lang from the URL when present', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?lang=it'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('it');
+    });
+
+    test('ignores unsupported locales', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?lang=sv'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('en');
+    });
+
+    test('ignores other parameters', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?enable=language'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('en');
+    });
+
+    test('uses navigator language property for default if supported', () => {
+        Object.defineProperty(window.navigator,
+            'language',
+            {value: 'pt-BR'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('pt-br');
+    });
+
+    test('ignores navigator language property if unsupported', () => {
+        Object.defineProperty(window.navigator,
+            'language',
+            {value: 'da'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('en');
+    });
+
+    test('works with an empty locale', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?locale='}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('en');
+    });
+
+    test('if multiple, uses the first locale', () => {
+        Object.defineProperty(window.location,
+            'search',
+            {value: '?locale=de&locale=en'}
+        );
+        expect(detectLocale(supportedLocales)).toEqual('de');
+    });
+});