[backend][nodejs] Add sample test

backend/nodejs/test/test.js

@@ -0,0 +1,9 @@
+var assert = require('assert');
+
+describe('Array', function () {
+    describe('#indexOf', function () {
+        it('should return -1 when the value is not present', function () {
+            assert.strictEqual([1, 2, 3].indexOf(4), -1);
+        });
+    })
+})