Add createDateTimeFormat to format dates based on locale

1 files changed, 43 insertions, 0 deletions

diff --git a/spec/javascripts/locale/index_spec.js b/spec/javascripts/locale/index_spec.js
new file mode 100644
index 00000000000..0f685c6d69d
--- /dev/null
+++ b/spec/javascripts/locale/index_spec.js
@@ -0,0 +1,43 @@
+import { createDateTimeFormat, languageCode } from '~/locale';
+
+const setLanguage = (languageCode) => {
+  const htmlElement = document.querySelector('html');
+
+  if (languageCode) {
+    htmlElement.setAttribute('lang', languageCode);
+  } else {
+    htmlElement.removeAttribute('lang');
+  }
+};
+
+describe('locale', () => {
+  afterEach(() => {
+    setLanguage(null);
+  });
+
+  describe('languageCode', () => {
+    it('parses the lang attribute', () => {
+      setLanguage('ja');
+
+      expect(languageCode()).toBe('ja');
+    });
+
+    it('falls back to English', () => {
+      setLanguage(null);
+
+      expect(languageCode()).toBe('en');
+    });
+  });
+
+  describe('createDateTimeFormat', () => {
+    beforeEach(() => {
+      setLanguage('de');
+    });
+
+    it('creates an instance of Intl.DateTimeFormat', () => {
+      const dateFormat = createDateTimeFormat({ year: 'numeric', month: 'long', day: 'numeric' });
+
+      expect(dateFormat.format(new Date(2015, 6, 3))).toBe('3. Juli 2015');
+    });
+  });
+});