玩笑错误 TypeError: (0 , _jest.test) 不是函数

我收到错误：

类型错误：（0，_jest.test）不是一个函数

当尝试使用时npm test.

我认为这可能与配置有关。我该如何解决这个问题？

File sum.js

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

export default sum

File tests/sum.test.js

import sum from '../src/sum.js'
import { test, expect } from 'jest'

test('adds 1 + 2 to equal 3', () => {
  expect(sum(1, 2)).toBe(3)
})

File 包.json

"devDependencies": {
    "babel-eslint": "7.1.1",
    "eslint": "3.18.0",
    "eslint-plugin-react": "6.10.0",
    "standard": "9.0.2",
    "webpack": "2.2.1",
    "jest": "21.0.1",
    "jest-cli": "21.0.1",
    "babel-jest": "21.0.0",
    "regenerator-runtime": "0.11.0"
},

and

"scripts": {
    "test": "standard && jest",
    "format": "standard --fix",
    "start": "webpack-dev-server --config webpack.config.dev.js",
    "build": "webpack --config webpack.config.prod.js"
},

删除这一行：

import { test, expect } from 'jest'

您不需要从 Jest 导入任何内容。看example https://facebook.github.io/jest/docs/en/getting-started.html.