anagram.js

function checkAnagram({word1, word2, anagramMap, alreadyInMap}) {
  let isAnagram = true;
  if (word2.length === word1.length) {
    for (let j = 0; j < word2.length; j++) {
          let current = word2[j];
          if (word1.indexOf(current) === -1) {
            isAnagram = false;         
            break;
          }
      }
      if (isAnagram) {
        alreadyInMap.add(word2);
        if (Array.isArray(anagramMap[word1])) {
            anagramMap[word1].push(word2);
        } else {
            anagramMap[word1] = [word1, word2];
        }
      }
  }
}

function anagrams(words) {
    const anagramMap = {};
    const alreadyInMap = new Set();
    words.forEach((word1, i) => {
      if (!alreadyInMap.has(word1)) {
        words.forEach((word2, index) => {
            if (i !== index) {
              checkAnagram({word1, word2, anagramMap, alreadyInMap});
            }
        })
      }
    })
    const arrFirstItems = []
    for (let item in anagramMap) {
      anagramMap[item].sort();
        arrFirstItems.push({value: anagramMap[item][0], key: item});
    }
    arrFirstItems.sort((a,b) => {
        if (a.value < b.value) {
          return -1;
        };
    })
    let resultsArr = [];
    for (let i = 0; i < arrFirstItems.length; i++) {
        resultsArr = resultsArr.concat(anagramMap[arrFirstItems[i].key])
    }
    return resultsArr;
}

const wordArray = ['reap', 'soil', 'hams', 'team', 'oils', 'meat', 'pear', 'mash'];
console.log(anagrams(wordArray)); /* [
  'hams', 'mash',
  'meat', 'team',
  'oils', 'soil',
  'pear', 'reap'
] */