Add unit tests for Trie/unique-word-count

Author: qualitymanifest

src/_DataStructures_/Trees/Trie/unique-word-count/index.test.js

@@ -0,0 +1,26 @@
+const Trie = require('../index');
+const uniqueWordCount = require('.');
+
+describe('Trie Unique Word Count', () => {
+  it('counts an empty trie', () => {
+    const trie = new Trie();
+    const wordCount = uniqueWordCount(trie.root);
+    expect(wordCount).toEqual(0);
+  });
+
+  it('counts unique words', () => {
+    const trie = new Trie();
+    const words = ['one', 'two', 'three', 'four'];
+    words.forEach(word => trie.insert(word));
+    const wordCount = uniqueWordCount(trie.root);
+    expect(wordCount).toEqual(4);
+  });
+
+  it('does not count duplicate words', () => {
+    const trie = new Trie();
+    const words = ['one', 'one', 'two', 'three'];
+    words.forEach(word => trie.insert(word));
+    const wordCount = uniqueWordCount(trie.root);
+    expect(wordCount).toEqual(3);
+  });
+});