jest

Question 1

to run tests in create-react-app, you type

Answer 1

npm test

Question 2

to create a basic react unit test (tests one thing), type

Answer 2

import { myFuncName } from ‘./App’

test('testName', ()=> {
  const myFuncResult = myFuncName('my_test_param')
  expect(myFuncName).toBe('value')
})

Question 3

some common assertions are

Answer 3

expect(myFuncName).toBeTruthy()
expect(myFuncName).toBe(param)
expect(myFuncName).toEqual(param)
expect(myFuncName).toBeGreaterThan(param)
expect(myFuncName).toBeInstanceOf(param)

Question 4

To create a jest mock function

Answer 4

const myFuncName = jest.fn(()=> “string”)