1 files changed, 28 insertions, 0 deletions
diff --git a/spec/frontend/__helpers__/local_storage_helper_spec.js b/spec/frontend/__helpers__/local_storage_helper_spec.js
new file mode 100644
index 00000000000..5d9961e7631
--- /dev/null
+++ b/spec/frontend/__helpers__/local_storage_helper_spec.js
@@ -0,0 +1,28 @@
+import { useLocalStorageSpy } from './local_storage_helper';
+
+describe('block before helper is installed', () => {
+  it('should leave original localStorage intact', () => {
+    expect(localStorage.getItem).toEqual(expect.any(Function));
+    expect(jest.isMockFunction(localStorage.getItem)).toBe(false);
+  });
+});
+
+describe('localStorage helper', () => {
+  useLocalStorageSpy();
+
+  it('mocks localStorage but works exactly like original localStorage', () => {
+    localStorage.setItem('test', 'testing');
+    localStorage.setItem('test2', 'testing');
+
+    expect(localStorage.getItem('test')).toBe('testing');
+
+    localStorage.removeItem('test', 'testing');
+
+    expect(localStorage.getItem('test')).toBe(null);
+    expect(localStorage.getItem('test2')).toBe('testing');
+
+    localStorage.clear();
+
+    expect(localStorage.getItem('test2')).toBe(null);
+  });
+});