Rec vs Loop Fibonacci for teaching purposes

fibonacci.js

function FibonacciSeqRec(n) {
  const fib = (seq) => {
    if (seq.length === n) return seq
    if (seq.length < 2) seq.push(1)
    else seq.push(seq[seq.length - 2] + seq[seq.length - 1])
    return fib(seq)
  }
  return fib([])
}

function FibonacciSeqLoop(n) {
  let seq = []
  while (seq.length < n) {
    if (seq.length < 2) seq.push(1)
    else seq.push(seq[seq.length - 2] + seq[seq.length - 1])
  }
  return seq
}

module.exports = { FibonacciSeqRec, FibonacciSeqLoop }

package.json

{
  "name": "fibonacci",
  "version": "1.0.0",
  "description": "",
  "main": "fib.js",
  "scripts": {
    "test": "node test.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "tape": "^4.9.0"
  }
}

test.js

const test = require('tape')
const { FibonacciSeqRec, FibonacciSeqLoop } = require('./fibonacci')

test('Should create fibonacci sequence till 233', t => {
  const expected = [1,1,2,3,5,8,13,21,34,55,89,144,233]
  t.deepEqual(FibonacciSeqRec(expected.length), expected)
  t.end()
})

test('Should create fibonacci sequence till 233', t => {
  const expected = [1,1,2,3,5,8,13,21,34,55,89,144,233]
  t.deepEqual(FibonacciSeqLoop(expected.length), expected)
  t.end()
})