Codecademy export

main.js

// Returns a random DNA base
const returnRandBase = () => {
  const dnaBases = ['A', 'T', 'C', 'G']
  return dnaBases[Math.floor(Math.random() * 4)] 
}

// Returns a random single stand of DNA containing 15 bases
const mockUpStrand = () => {
  const newStrand = []
  for (let i = 0; i < 15; i++) {
    newStrand.push(returnRandBase())
  }
  return newStrand
}

const pAequorFactory = (number, dna) => {
  const mutate = () => {
    let randomNum = Math.floor(Math.random() * 16);
    let newBase = returnRandBase();
    if (this.dna[randomNum] === newBase) {
      newBase = returnRandBase();
    } else {
      this.dna[randomNum] = newBase;
    }
    return this.dna;
  }
  return {
    specimenNum: number,
    dna: dna,
    mutate
  }
}

let pA1 = pAequorFactory(1, mockUpStrand());
console.log(pA1.dna);
console.log(pA1.mutate());