Add jest test to ensure consistency between AnimatedMock and AnimatedImplementation

Summary: Flow doesn't guarantee that AnimatedMock and AnimatedImplementation won't diverge. Christoph suggested a quick jest test in D13811035

Reviewed By: cpojer

Differential Revision: D13953915

fbshipit-source-id: ba5aeafded429113cc60a6250b5b29d2f8c8ab28

Libraries/Animated/src/__tests__/AnimatedMock-test.js

@@ -0,0 +1,29 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @emails oncall+react_native
+ */
+
+'use strict';
+
+const AnimatedMock = require('AnimatedMock');
+const AnimatedImplementation = require('AnimatedImplementation');
+
+describe('Animated Mock', () => {
+  it('matches implementation keys', () => {
+    expect(Object.keys(AnimatedMock)).toEqual(
+      Object.keys(AnimatedImplementation),
+    );
+  });
+  it('matches implementation params', () => {
+    Object.keys(AnimatedImplementation).forEach(key =>
+      expect(AnimatedImplementation[key].length).toEqual(
+        AnimatedMock[key].length,
+      ),
+    );
+  });
+});