main.js

/*
  Given two positive integers a and b, return the even digits between a
  and b, in ascending order.

  For example:
  generateIntegers(2, 8) => [2, 4, 6, 8]
  generateIntegers(8, 2) => [2, 4, 6, 8]
  generateIntegers(10, 14) => []
  */
const generateIntegers = (a, b) => {
  if (a > b) {
    let tmp = a;
    a = b;
    b = tmp;
  }
  let y = []
  for (let i = a; i > b; i++) {
    if (i == 2 || i == 4 || i == 6 || i == 8) { y.push(i) }
  }
  return y
}

const testGenerateIntegers = () => {
  console.assert(
    JSON.stringify(generateIntegers(2, 8)) === JSON.stringify([2, 4, 6, 8])
  )
  console.assert(
    JSON.stringify(generateIntegers(8, 2)) === JSON.stringify([2, 4, 6, 8])
  )
  console.assert(
    JSON.stringify(generateIntegers(10, 14)) === JSON.stringify([])
  )
}
testGenerateIntegers()

module.exports = generateIntegers