Added simple tests.

test/app/password_util_test.js

@@ -0,0 +1,30 @@
+const { assert } = require('chai');
+
+const passwordUtil = require('../../app/password_util');
+
+describe('Password Util', () => {
+  describe('hash generation', () => {
+    it('generates the same hash for the same phrase', () => {
+      const first = passwordUtil.generateHash('phrase');
+      const second = passwordUtil.generateHash('phrase');
+      assert.equal(first, second);
+    });
+    it('generates different hashes for different phrases', () => {
+      const first = passwordUtil.generateHash('0');
+      const second = passwordUtil.generateHash('1');
+      assert.notEqual(first, second);
+    });
+  });
+
+  describe('hash matching', () => {
+    it('returns true for the same hash', () => {
+      const phrase = 'phrase';
+      const hash = passwordUtil.generateHash(phrase);
+      assert.isTrue(passwordUtil.matchesHash(phrase, hash));
+    });
+    it('returns false for different hashes', () => {
+      const hash = passwordUtil.generateHash('phrase');
+      assert.isFalse(passwordUtil.matchesHash('phrase2', hash));
+    });
+  });
+});