Often when testing, you use the actual result to create your assertion and have to manually update it as you make changes to the feature. With Jest snapshot testing, you can let Jest do this part for you and write more tests and features faster and w…

For some React component testing, we have common setup in each test file: import { render } from 'react-testing-library' import 'jest-dom/extend-expect' import 'react-testing-library/cleanup-after-each' We want to setup a common place for JEST to loa…

为什么要做单元测试 作为一个前端工程师,我是很想去谢单元测试的,因为每天的需求很多,还要去编写测试代码,感觉时间都不够用了. 不过最近开发了一个比较复杂的项目,让我感觉一旦项目大了.复杂了,而且还是多人维护一个应用,编写测试代码, 还是很有必要的.毕竟这样做完之后,后边的维护会轻松很多. 单元测试 测试代码的最小单元,一个函数就是一个单元 测试工具 主要用到的测试工具是 jest 和 enzyme jest . enzyme 介绍 jest 是 facebook 发布的一个开源的,基于 jasm…

1. initialize project create a folder project Now we'll turn this folder into an npm package. npm init -y This creates a package.json file with default values. 2. Install react typescript dependencies First ensure Webpack is installed. npm i webpack…

Install Jest 1.install jest dependencies jest @types/jest ts-jest -D 2.jest.config.js module.exports = { "roots": [ "<rootDir>/src" ], "transform": { "^.+\\.tsx?$": "ts-jest" }, "testRegex"…

Transpile Modules with Babel in Jest Tests Jest automatically loads and applies our babel configuration. However, because our project takes advantage of tree shaking with webpack, our babel configuration disables transpiling modules. For Jest to work…

Testing models is straightforward. Especially because MST provides powerful tools to track exactly how your state changes over time. Track snapshots, action invocations or even patches to verify the correctness of your actions! In this lesson you wil…

The problem we face daily when we do testing: The Data structure may changing, component outlook might changing... this makes it hard for us do testing. Imaging when the data structure changed, your tests broken, when you need to change the tests acc…

ava也提供了类似jest 的snapshot 测试,可以用来方便的测试web 组件,以下是一个简单的试用, 同时包含了自己碰到问题,以及解决方法,以及一些参考链接 使用typescript 以及tsx,测试react 组件 环境准备 项目结构   ├── package.json ├── src │ ├── app.ts │ ├── hello-component.tsx │ └── userlogin.tsx ├── tests │ ├── app.js │ ├── hello-compon…

1.为什么要使用单元测试工具? 因为代码之间的相互调用关系,又希望测试过程单元相互独立,又能正常运行,这就需要我们对被测函数的依赖函数和环境进行mock,在测试数据输入.测试执行和测试结果检查方面存在很多相似性,测试工具正是为我们在这些方面提供了方便. 所谓单元测试也就是对每个单元进行测试,通俗的将一般针对的是函数,类或单个组件,不涉及系统和集成.单元测试是软件测试的基础测试. 2.React 的标配测试工具 Jest. Jest主要有以下特点: 1.适应性:Jest是模块化.可扩展和可配置的.…