add test

test/index.js

@@ -0,0 +1,21 @@
+'use strict';
+
+const helper = require ('../index');
+const test = require ('ava');
+
+test ('create hash', async (t) => {
+  const hash = await helper.hash ('foo');
+  t.is (typeof hash, 'string');
+});
+
+test ('validate', async (t) => {
+  const hash = await helper.hash ('foo');
+  const valid = await helper.verify (hash, 'foo');
+  t.is (valid, true);
+});
+
+test ('fail validation', async (t) => {
+  const hash = await helper.hash ('foo');
+  const valid = await helper.verify (hash, 'bar');
+  t.is (valid, false);
+});