Add latest changes from gitlab-org/gitlab@master

1 files changed, 63 insertions, 0 deletions

diff --git a/spec/frontend/lib/utils/tappable_promise_spec.js b/spec/frontend/lib/utils/tappable_promise_spec.js
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+++ b/spec/frontend/lib/utils/tappable_promise_spec.js
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+import TappablePromise from '~/lib/utils/tappable_promise';
+
+describe('TappablePromise', () => {
+  it('allows a promise to have a progress indicator', () => {
+    const pseudoProgress = [0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1];
+    const progressCallback = jest.fn();
+    const promise = new TappablePromise((tap, resolve) => {
+      pseudoProgress.forEach(tap);
+      resolve('done');
+
+      return 'returned value';
+    });
+
+    return promise
+      .tap(progressCallback)
+      .then((val) => {
+        expect(val).toBe('done');
+        expect(val).not.toBe('returned value');
+
+        expect(progressCallback).toHaveBeenCalledTimes(pseudoProgress.length);
+
+        pseudoProgress.forEach((progress, index) => {
+          expect(progressCallback).toHaveBeenNthCalledWith(index + 1, progress);
+        });
+      })
+      .catch(() => {});
+  });
+
+  it('resolves with the value returned by the callback', () => {
+    const promise = new TappablePromise((tap) => {
+      tap(0.5);
+      return 'test';
+    });
+
+    return promise
+      .tap((progress) => {
+        expect(progress).toBe(0.5);
+      })
+      .then((value) => {
+        expect(value).toBe('test');
+      });
+  });
+
+  it('allows a promise to be rejected', () => {
+    const promise = new TappablePromise((tap, resolve, reject) => {
+      reject(new Error('test error'));
+    });
+
+    return promise.catch((e) => {
+      expect(e.message).toBe('test error');
+    });
+  });
+
+  it('rejects the promise if the callback throws an error', () => {
+    const promise = new TappablePromise(() => {
+      throw new Error('test error');
+    });
+
+    return promise.catch((e) => {
+      expect(e.message).toBe('test error');
+    });
+  });
+});