added unit test for Trie

package.json

@@ -21,4 +21,4 @@
     "eslint-plugin-import": "^2.14.0",
     "jest": "^25.0.0"
   }
-}
+}

src/_DataStructures_/Trees/Trie/total-words-in-trie/index.js

@@ -1,6 +1,4 @@
 // eslint-disable-next-line no-unused-vars
-const Trie = require('../index');
-
 function totalWords(root) {
   let result = 0;
   if (root.isEndOfWord) {
@@ -20,4 +18,4 @@ function totalWords(root) {
 // words.forEach(word => trie.insert(word));
 // console.log(totalWords(trie.root));
 
-module.exports = totalWords;
+module.exports = { totalWords };

src/_DataStructures_/Trees/Trie/total-words-in-trie/index.test.js

@@ -0,0 +1,25 @@
+const trie = require('../index');
+const wordcounts = require('./index');
+
+describe('Trees Total words in trie', () => {
+    //case with non-empty array
+    it("Solution for this testarray is 5", () => {
+        const testarray = ["one", "two", "three", "four", "five"];
+        const t = new trie();
+
+        for (let i of testarray) {
+            t.insert(i);
+        }
+        expect(wordcounts.totalWords(t.root)).toEqual(testarray.length);
+    })
+
+    //case with empty array
+    it("Solution for this empty_array is empty", () => {
+        const empty_array = [];
+        const t = new trie();
+        for (let j of empty_array) {
+            t.insert(j);
+        }
+        expect(wordcounts.totalWords(t.root)).toEqual(0);
+    })
+})