Anagram refactor

anagram/anagram_test.spec.js

@@ -1,58 +1,75 @@
-var Anagram = require('./anagram');
+var anagram = require('./anagram');
 
 describe('Anagram', function() {
 
   it("no matches",function() {
-    var detector = new Anagram("diaper");
-    var matches = detector.match([ "hello", "world", "zombies", "pants"]);
+    var subject = anagram("diaper");
+    var matches = subject.matches([ "hello", "world", "zombies", "pants"]);
+
     expect(matches).toEqual([]);
   });
 
   xit("detects simple anagram",function() {
-    var detector = new Anagram("ant");
-    var matches = detector.match(['tan', 'stand', 'at']);
+    var subject = anagram("ant");
+    var matches = subject.matches(['tan', 'stand', 'at']);
+
     expect(matches).toEqual(['tan']);
   });
 
   xit("does not detect false positives",function() {
-    var detector = new Anagram("galea");
-    var matches = detector.match(["eagle"]);
+    var subject = anagram("galea");
+    var matches = subject.matches(["eagle"]);
+
     expect(matches).toEqual([]);
   });
 
   xit("detects multiple anagrams",function() {
-    var detector = new Anagram("master");
-    var matches = detector.match(['stream', 'pigeon', 'maters']);
+    var subject = anagram("master");
+    var matches = subject.matches(['stream', 'pigeon', 'maters']);
+
     expect(matches).toEqual(['stream', 'maters']);
   });
 
   xit("does not detect anagram subsets",function() {
-    var detector = new Anagram("good");
-    var matches = detector.match(['dog', 'goody']);
+    var subject = anagram("good");
+    var matches = subject.matches(['dog', 'goody']);
+
     expect(matches).toEqual([]);
   });
 
   xit("detects anagram",function() {
-    var detector = new Anagram("listen");
-    var matches = detector.match(['enlists', 'google', 'inlets', 'banana']);
+    var subject = anagram("listen");
+    var matches = subject.matches(['enlists', 'google', 'inlets', 'banana']);
+
     expect(matches).toEqual(['inlets']);
   });
 
   xit("detects multiple anagrams",function() {
-    var detector = new Anagram("allergy");
-    var matches = detector.match(['gallery', 'ballerina', 'regally', 'clergy', 'largely', 'leading']);
+    var subject = anagram("allergy");
+    var matches = subject.matches(['gallery', 'ballerina', 'regally', 'clergy', 'largely', 'leading']);
+
     expect(matches).toEqual(['gallery', 'regally', 'largely']);
   });
 
   xit("detects anagrams case-insensitively",function() {
-    var detector = new Anagram("Orchestra");
-    var matches = detector.match(['cashregister', 'Carthorse', 'radishes']);
+    var subject = anagram("Orchestra");
+    var matches = subject.matches(['cashregister', 'Carthorse', 'radishes']);
+
     expect(matches).toEqual(['Carthorse']);
   });
 
   xit("does not detect a word as its own anagram",function() {
-    var detector = new Anagram("banana");
-    var matches = detector.match(['Banana']);
+    var subject = anagram("banana");
+    var matches = subject.matches(['Banana']);
+
     expect(matches).toEqual([]);
   });
+
+  xit("matches() accepts string arguments",function() {
+    var subject = anagram("ant");
+    var matches = subject.matches("stand", "tan", "at");
+
+    expect(matches).toEqual(["tan"]);
+  });
+
 });

anagram/example.js

@@ -1,34 +1,30 @@
-(function() {
-  'use strict';
+"use strict";
+module.exports = anagram;
 
-  function Anagram(word) {
-    this.word = word.toLowerCase();
-  }
-
-  Anagram.prototype.match = function(words) {
-    var matches = [];
-
-    for(var i = 0; i < words.length; i++) {
-      var currentWord = words[i];
+function anagram(word) {
+  return {
+    // public API
+    matches: matches.bind(this, word)
+  };
+}
 
-      if (currentWord.length == this.word.length && currentWord.toLowerCase() != this.word) {
-        var currentWordLetters = currentWord.toLowerCase().split('').sort();
-        var matchingWordLetters = this.word.split('').sort();
+function matches(word, words) {
+  words = Array.isArray(words) ? words : [].slice.call(arguments, 1);
 
-        var isMatch = true;
+  return words.filter(function (candidate) {
+    return !sameWord(word, candidate) && isAnagram(word, candidate);
+  });
+}
 
-        for (var j = 0; j < currentWordLetters.length; j++) {
-          if (currentWordLetters[j] != matchingWordLetters[j]) {
-            isMatch = false;
-          }
-        }
+function sameWord(word, candidate) {
+  return word.toLowerCase() === candidate.toLowerCase();
+}
 
-        if (isMatch) { matches.push(currentWord); }
-      }
+function isAnagram(word, candiate) {
+  return normalize(word) === normalize(candiate);
+}
 
-    }
-    return matches;
-  };
+function normalize(string) {
+  return string.toLowerCase().split("").sort().toString();
+}
 
-  module.exports = Anagram;
-})();