1 files changed, 43 insertions, 0 deletions
diff --git a/spec/frontend/helpers/mock_window_location_helper.js b/spec/frontend/helpers/mock_window_location_helper.js
new file mode 100644
index 00000000000..175044d1fce
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+++ b/spec/frontend/helpers/mock_window_location_helper.js
@@ -0,0 +1,43 @@
+/**
+ * Manage the instance of a custom `window.location`
+ *
+ * This only encapsulates the setup / teardown logic so that it can easily be
+ * reused with different implementations (i.e. a spy or a [fake][1])
+ *
+ * [1]: https://stackoverflow.com/a/41434763/1708147
+ *
+ * @param {() => any} fn Function that returns the object to use for window.location
+ */
+const useMockLocation = fn => {
+  const origWindowLocation = window.location;
+  let currentWindowLocation;
+
+  Object.defineProperty(window, 'location', {
+    get: () => currentWindowLocation,
+  });
+
+  beforeEach(() => {
+    currentWindowLocation = fn();
+  });
+
+  afterEach(() => {
+    currentWindowLocation = origWindowLocation;
+  });
+};
+
+/**
+ * Create an object with the location interface but `jest.fn()` implementations.
+ */
+export const createWindowLocationSpy = () => {
+  return {
+    assign: jest.fn(),
+    reload: jest.fn(),
+    replace: jest.fn(),
+    toString: jest.fn(),
+  };
+};
+
+/**
+ * Before each test, overwrite `window.location` with a spy implementation.
+ */
+export const useMockLocationHelper = () => useMockLocation(createWindowLocationSpy);