Solution

package.json

@@ -18,7 +18,8 @@
   },
   "homepage": "https://github.com/MoveInc/coding_exercise#readme",
   "dependencies": {
-    "express": "^4.17.1"
+    "express": "^4.17.1",
+    "lodash": "^4.17.21"
   },
   "devDependencies": {
     "eslint": "^7.22.0",

src/anagram-service.js

@@ -1,18 +1,17 @@
-const fs = require('fs');
-
+const fs = require("fs");
+const lodash = require("lodash");
 /**
- * Looks up anagrams of a given word based on the 
+ * Looks up anagrams of a given word based on the
  * word dictionary provided in the constructor.
  */
 class AnagramService {
-
   /**
    * Creates an AnagramService instance
    * @param {string} dictionaryFilePath Path to the dictionary file
    */
   constructor(dictionaryFilePath) {
     this.dictionaryFilePath = dictionaryFilePath;
-    this.wordsMap = new Map();
+    this.wordsArray = [];
   }
 
   /**
@@ -26,10 +25,10 @@ class AnagramService {
           return reject(err);
         }
 
-        const lines = data.toString().split('\n');
+        const lines = data.toString().split("\n");
 
         lines.forEach((line) => {
-          this.wordsMap.set(line.toLowerCase(), [line]); 
+          this.wordsArray.push(line.toLowerCase().trim());
         });
         return resolve(this);
       });
@@ -38,16 +37,38 @@ class AnagramService {
 
   /**
    * Returns all anagrams for the given term
-   * @param {string} term The term to find anagrams for 
+   * @param {string} term The term to find anagrams for
    * @returns A string[] of anagram matches
    */
   async getAnagrams(term) {
-    if (!this.wordsMap || this.wordsMap.size === 0) {
-      throw Error('Error: Dictionary not initialized');
+    if (!this.wordsArray || this.wordsArray.length === 0) {
+      throw Error("Error: Dictionary not initialized");
     }
+    const termCharacterMap = this.getCharacterMap(term);
+
+    const filteredWordsMapKeys = this.wordsArray.filter((word) => {
+      const hasSameLength = word.length === term.length;
+      if (!hasSameLength) return false;
+      const wordCharacterMap = this.getCharacterMap(word);
+      const MapsAreEqual = lodash.isEqual(wordCharacterMap, termCharacterMap);
+
+      return hasSameLength && MapsAreEqual;
+    });
+
+    return filteredWordsMapKeys;
+  }
 
-    // TODO: The anagram lookup 🤦‍♂️
-    return this.wordsMap.get(term);
+  getCharacterMap(word) {
+    const map = {};
+    for (const index in Array.from(word).sort()) {
+      const character = word[index];
+      if (map[character]) {
+        map[character]++;
+      } else {
+        map[character] = 1;
+      }
+    }
+    return map;
   }
 }