Jest

起步

安装

npm install --save-dev jest

pageckage.json配置

{
  "scripts": {
    "test": "jest"
  }
}

Expect

Expect是一个函数，第一个参数接收value,后面可接链式属性判断

• expect(value)
  • expect(value).not.toEqual: 与后面等式取反比较
  • toEqual(compareValue): value 与 compareValue必须完全相等

自定义校验方法

// 查询对象key值是否存在对象中
expect.extend({
    toContainKeys(received, keys) {
        const receivedKeys = Object.keys(received);
        const pass = keys.every((val => receivedKeys.includes(val)));
        if (pass) {
            return {
                message: () =>
                `expected ${JSON.stringify(received)} have contain ${receivedKeys}`,
                pass: true,
            };
        } else {
            return {
                message: () =>
                `expected ${JSON.stringify(received)} don't have contain ${receivedKeys}`,
                pass: false,
            };
        }
    }
});