// The function has been called exactly once expect(someMockFunction.mock.calls.length).toBe(1); // 'first arg' was the first arg of the first call to the function expect(someMockFunction.mock.calls[0][0]).toBe(
Using toHaveBeenCalledWith is straightforward. Here’s the basic syntax: javascriptexpect(mockFunction).toHaveBeenCalledWith(arg1,arg2,...); Example Suppose you have a function,sendGreeting, that calls another function, sendGreeting, with a message: ...
Should note that this also works if mockedModuleFunction is being called from another function. So say mockedModuleFunction is called by otherFunction. For example if otherFunction looked like this: function otherFunction() { return mockedModuleFunction() } Then this will also work. const mocked...
import demoFunction from './demo' import Util from './util' jest.mock('./util') //jest.mock 发现uitl是一个类,会自动把类的构造函数和方法变成jest.fn() /* const Util= jest.fn() until.prototype.a = jest.fn() until.prototype.b = jest.fn() 如果不满意默认处理,可以自定义在文件__moc...
ES6 classes are constructor functions that has some syntactic sugar. Therefore, any mock for an ES6 class has to be a function or has to be an actual ES6 class (which is, again, another function). So you can mock them using mock functions. ...
Jest - Mock in Jest Mocking is just replacing a function by another called a mocking function. In Jest mocking function can replace the code executed but they also record all call made to them creating a command... Node - NODE_PATH NODE_PATH is: a process environment variable that contai...
The clipping region cannot be cleared because it's based on the stack values and when the.clip()function is called. Override default mock return value You can override the default mock return value in your test to suit your need. For example, to override return value oftoDataURL: ...
解决方案:1.使用jest.setTimeout函数增加测试用例的超时时间。2.尽量避免在测试用例中执行耗时的操作,可以使用jest.fn()或jest.mock()进行模拟。 //example.test.js constfetch=require(node-fetch); jest.setTimeout(10000);//设置超时时间为10秒
Jest有一个好处,就是不用配置也能用,开箱即用,它提供了断言,函数的mock等常用的测试功能。npm install jest --save-dev, 安装jest 之后,就可以使用它进行单元测试了。打开git bash,输入mkdir jest-test && cd jest-test && npm init -y, 新建jest-test 项目并初始化为node项目。再npm install jest --...
//使用jest提供的mock函数来解决这个问题 const func = jest.fn(); //测试callback函数,如果在执行之后,func函数被调用 //说明callback函数被成功执行了 runCallback(func); expect(func).toBeCalled(); //测试用例通过,说明func函数被调用 //mock函数,可以捕获函数的调用 // console.log(func.mock); // ...