Google JS Test是一個運行于V8 JavaScript引擎下的Javascript單元測試框架，其在Google內部負責對Chrome的快速JS執行速度進行測試，現在Google以開源工程開放大家使用。Google JS Test主要特性：
- 超快的啟動速度和執行時間，不需要在瀏覽器里運行
- 清爽而具有可讀性的輸出內容
- 也有一個可選的基于瀏覽器的測試器，可在JS修改的時候刷新
- 其樣式和語義跟Google Test for C++類似
- 內置的Mocking框架只需要最簡單的樣板代碼（比如no $tearDown or $verifyAll 請求），其樣式和語義基于Google C++ Mocking Framework
- 匹配系統允許表達式測試，并可直觀的閱讀輸出的錯誤提示，內置了很多匹配器，用戶也可自行添加
01 | function UserInfoTest() { |
02 | // Each test function gets its own instance of UserInfoTest, so tests can |
03 | // use instance variables to store state that doesn't affect other tests. |
04 | // There's no need to write a tearDown method, unless you modify global |
07 | // Create an instance of the class under test here, giving it a mock |
08 | // function that we also keep a reference to below. |
09 | this.getInfoFromDb_ = createMockFunction(); |
10 | this.userInfo_ = new UserInfo(this.getInfoFromDb_); |
12 | registerTestSuite(UserInfoTest); |
14 | UserInfoTest.prototype.formatsUSPhoneNumber = function() { |
15 | // Expect a call to the database function with the argument 0xdeadbeef. When |
16 | // the call is received, return the supplied string. |
17 | expectCall(this.getInfoFromDb_)(0xdeadbeef) |
18 | .willOnce(returnWith('phone_number: "650 253 0000"')); |
20 | // Make sure that our class returns correctly formatted output. |
21 | expectEq('(650) 253-0000',this.userInfo_.getPhoneForId(0xdeadbeef)); |
24 | UserInfoTest.prototype.returnsLastNameFirst = function() { |
25 | expectCall(this.getInfoFromDb_)(0xdeadbeef) |
26 | .willOnce(returnWith('given_name: "John" family_name: "Doe"')); |
28 | // Make sure that our class puts the last name first. |
29 | expectEq('Doe, John', this.userInfo_.getNameForId(0xdeadbeef)); |