1 files changed, 39 insertions, 0 deletions
diff --git a/spec/frontend/lib/utils/favicon_spec.js b/spec/frontend/lib/utils/favicon_spec.js
new file mode 100644
index 00000000000..1b986432b8a
--- /dev/null
+++ b/spec/frontend/lib/utils/favicon_spec.js
@@ -0,0 +1,39 @@
+import { FaviconOverlayManager } from '@gitlab/favicon-overlay';
+import * as faviconUtils from '~/lib/utils/favicon';
+
+jest.mock('@gitlab/favicon-overlay');
+
+describe('~/lib/utils/favicon', () => {
+  afterEach(() => {
+    faviconUtils.clearMemoizeCache();
+  });
+
+  describe.each`
+    fnName                 | managerFn                                    | args
+    ${'setFaviconOverlay'} | ${FaviconOverlayManager.setFaviconOverlay}   | ${['test']}
+    ${'resetFavicon'}      | ${FaviconOverlayManager.resetFaviconOverlay} | ${[]}
+  `('$fnName', ({ fnName, managerFn, args }) => {
+    const call = () => faviconUtils[fnName](...args);
+
+    it('initializes only once when called', async () => {
+      expect(FaviconOverlayManager.initialize).not.toHaveBeenCalled();
+
+      // Call twice so we can make sure initialize is only called once
+      await call();
+      await call();
+
+      expect(FaviconOverlayManager.initialize).toHaveBeenCalledWith({
+        faviconSelector: '#favicon',
+      });
+      expect(FaviconOverlayManager.initialize).toHaveBeenCalledTimes(1);
+    });
+
+    it('passes call to manager', async () => {
+      expect(managerFn).not.toHaveBeenCalled();
+
+      await call();
+
+      expect(managerFn).toHaveBeenCalledWith(...args);
+    });
+  });
+});