From 24fee29f7a8ab328bb35e66d145d6b9c2d018c1d Mon Sep 17 00:00:00 2001
From: Kudo Chien <ckchien@gmail.com>
Date: Thu, 28 Nov 2024 05:05:31 -0800
Subject: [PATCH] Add useColorScheme mock test (#47988)

Summary:
add a jest test to test when `useColorScheme` is not mocked. following up https://github.com/facebook/react-native/pull/47629#issuecomment-2491534678

## Changelog:

[GENERAL] [ADDED] - Add useColorScheme mock test

Pull Request resolved: https://github.com/facebook/react-native/pull/47988

Test Plan: ci passed

Reviewed By: javache

Differential Revision: D66573172

Pulled By: blakef

fbshipit-source-id: 820227f6fc4e18a968b3181fad8f534a716f1e9e
---
 .../__tests__/useColorScheme-test.js          | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 packages/react-native/Libraries/Utilities/__tests__/useColorScheme-test.js

diff --git a/packages/react-native/Libraries/Utilities/__tests__/useColorScheme-test.js b/packages/react-native/Libraries/Utilities/__tests__/useColorScheme-test.js
new file mode 100644
index 00000000000..1ba2463968e
--- /dev/null
+++ b/packages/react-native/Libraries/Utilities/__tests__/useColorScheme-test.js
@@ -0,0 +1,39 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ * @oncall react_native
+ */
+
+import useColorScheme from '../useColorScheme';
+
+describe('useColorScheme', () => {
+  it('should return a mocked light theme by default', () => {
+    expect(jest.isMockFunction(useColorScheme)).toBe(true);
+    expect(useColorScheme()).toBe('light');
+  });
+
+  it('should have console.error when not using mock', () => {
+    const useColorSchemeActual = jest.requireActual<{
+      default: typeof useColorScheme,
+    }>('../useColorScheme').default;
+    const spy = jest.spyOn(console, 'error').mockImplementationOnce(() => {
+      // Simulate LogBox console.error() call to throw an error and stop the further execution
+      throw new Error('console.error() was called');
+    });
+
+    expect(() => {
+      useColorSchemeActual();
+    }).toThrow();
+
+    expect(spy).toHaveBeenCalledWith(
+      expect.stringMatching(
+        /Invalid hook call. Hooks can only be called inside of the body of a function component./,
+      ),
+    );
+  });
+});