Count word solution

countWords.js

const { deepStrictEqual } = require('assert')

const mutableApproach = (line) => {
  const words = {};
  line.split(' ').forEach((key) => {
    if (words[key]) {
      words[key] += 1;
      return;
    }
    words[key] = 1;
  });

  return words;
};

const functionalApproach = (line) =>
  line.split(' ').reduce((words, key) => {
    if (words[key]) {
      return { ...words, [key]: words[key] + 1 };
    }
    return { ...words, [key]: 1 };
  }, {});


const input = 'This is some random text and some raddom work';

const want = {
  This: 1,
  is: 1,
  some: 2,
  random: 1,
  text: 1,
  and: 1,
  raddom: 1,
  work: 1
};

deepStrictEqual(mutableApproach(input), want, "mutable approach failed");
deepStrictEqual(functionalApproach(input), want, "functional approach failed");

console.log('both test passed')