M2A_18.md

M2#A18 - TDD - some

'use strict'

const some = (arr, func) => {
  for (let i = 0; i < arr.length; i++){
    if(func(arr[i], i, arr)){
      return true
    }
  }
  return false
}

export default some

Testes

'use strict'

import { expect } from 'chai'
import some from './some'

it('some should be a function', () => {
  expect(some).to.be.a('function')
})

it('some([], (item) => item) should return false', () => {
  expect(some([], (item) => item)).to.not.be.ok
})


it('some([1, 2], (item) => item) should return true', () => {
  expect(some([1, 2], (item) => item)).to.be.ok
})

it('some([1, 2, 3], (item, index) => index % 2 === 0 ) should return true', () => {
  expect(some([1, 2, 3], (item, index) => index % 2 === 0 )).to.be.ok
})

it('some([1, 3, 5], (item, index) => item % 2 === 0 ) should return false', () => {
  expect(some([1, 3, 5], (item, index) => item % 2 === 0 )).to.not.be.ok
})


it('some([1, 2, 2], (item, index, array) => array.indexOf(2) === 1) should return true', () => {
  expect(some([1, 2, 2], (item, index, array) => array.indexOf(2) === 1)).to.be.ok
})