[Jest] Test 작성 - Matcher (toBe(), not.toBe(), toEqual(), toStrictEqual(), toBeNull(),toBeUndefined(),toBeDefined(),toBeTruthy(),toBeFalsy())

 간단한 테스트 작성

코드1. toBe()

//fn.js
const fn = {
  add : (num1,num2) => num1+num2
}

module.exports = fn

//fn.test.js
const fn = require('./fn')
test('1은 1이야',()=>{
  expect(1).toBe(1)
})

test('2더하기 3은 5야',()=>{
  expect(fn.add(2,3)).toBe(5)
})
test('3더하기 3은 5야',()=>{
  expect(fn.add(3,3)).toBe(5)
})

결과1.

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코드2. toBe(), not.toBe()

const fn = require('./fn')
test('1은 1이야',()=>{
  expect(1).toBe(1)
})

test('2더하기 3은 5야',()=>{
  expect(fn.add(2,3)).toBe(5)
})
test('3더하기 3은 5가 아니야',()=>{
  expect(fn.add(3,3)).not.toBe(5)
})

결과2

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코드3. toBe(), toEqual()

//fn.js
const fn = {
  add : (num1,num2) => num1+num2,
  makeUser:(name,age)=>({name,age})
}

module.exports = fn

//fn.test.js
const fn = require('./fn')
test('이름과 나이를 전달 받아서 객체를 변환', ()=>{
  expect(fn.makeUser('iseo',27)).toBe({
    name:'iseo',
    age:27,
  })
})
test('이름과 나이를 전달 받아서 객체를 변환', ()=>{
  expect(fn.makeUser('iseo',27)).toEqual({
    name:'iseo',
    age:27,
  })
})

결과3

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코드4. toEqual(), toStrictEqual()

const fn = require('./fn')

test('이름과 나이를 전달 받아서 객체를 변환', ()=>{
  expect(fn.makeUser('iseo',27)).toEqual({
    name:'iseo',
    age:27,
  })
})

test('이름과 나이를 전달 받아서 객체를 변환', ()=>{
  expect(fn.makeUser('iseo',27)).toStrictEqual({
    name:'iseo',
    age:27,
  })
})

결과4

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코드5. 인자 추가

//fn.js
const fn = {
  add : (num1,num2) => num1+num2,
  makeUser:(name,age,gender)=>({name,age,gender:undefined})
}

module.exports = fn

//fn.test.js
const fn = require('./fn')

test('이름과 나이를 전달 받아서 객체를 변환', ()=>{
  expect(fn.makeUser('iseo',27)).toEqual({
    name:'iseo',
    age:27,
  })
})

test('이름과 나이를 전달 받아서 객체를 변환', ()=>{
  expect(fn.makeUser('iseo',27)).toStrictEqual({
    name:'iseo',
    age:27,
  })
})

 

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코드6. toBeNull(),toBeUndefined(),toBeDefined(),toBeTruthy(),toBeFalsy()

//fn.test.js
const fn = require('./fn')

//toBeNull
//toBeUndefined
//toBeDefined

test('null은 null입니다',()=>{
  expect(null).toBeNull()
})

//toBeTruthy
//toBeFalsy
test('0은 false입니다',()=>{
  expect(fn.add(1,-1)).toBeFalsy()
})

결과6

---

코드7

const fn = require('./fn')

//toBeNull
//toBeUndefined
//toBeDefined

test('null은 null입니다',()=>{
  expect(null).toBeNull()
})

//toBeTruthy
//toBeFalsy
test('비어있지 않은 문자열은 true',()=>{
  expect(fn.add('Decision To','Leave')).toBeTruthy()
})

결과7