jest学习--01环境安装与es6/ts语法支持

创建项目添加jest依赖

mkdir jest-01
pnpm init -y
pnpm add jest

让jest支持es6语法

pnpm add babel-jest @babel/core @babel/preset-env -D

.babelrc

{
  "presets": [
    [
      "@babel/preset-env",
      {
        "targets": {
          "node": "current"
        }
      }
    ]
  ]
}

编写代码执行测试

demo01.js

export function sum(a, b){
    return a+b
}

demo01.spec.js

import {sum} from './demo01'

test('1 + 2等于3', () => {
    console.log(sum)
    expect(sum(1, 2)).toBe(3);
  });

让jest能测试ts代码

pnpm add @babel/preset-typescript ts-jest @jest/globals @types/jest -D

.babelrc

{
    "presets": [
      [
        "@babel/preset-env",
        {
          "targets": {
            "node": "current"
          }
        }
      ],
        "@babel/preset-typescript"
    ]
}

demo02.ts

export function plus(a:number,b:number):number{
    return a+b
}

demo02.spec.ts

import {describe, expect, test} from '@jest/globals';
import {plus} from './demo02'

describe('ts测试',()=>{
  test('1 + 2等于3', () => {
    console.log(plus)
    expect(plus(1, 2)).toBe(3);
  });
})