# Can we use Jest for unit test?
**URL:** https://discourse.nodered.org/t/can-we-use-jest-for-unit-test/13154
**Category:** General
**Created:** [11 July 2019 08:17 UTC](https://discourse.nodered.org/t/can-we-use-jest-for-unit-test/13154 "2019-07-11T08:17:16Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@fangzhu](https://discourse.nodered.org/u/fangzhu)
#### Post date: [11 July 2019 08:17 UTC](https://discourse.nodered.org/t/can-we-use-jest-for-unit-test/13154/1 "2019-07-11T08:17:16Z")
The example in the document uses mocha for unit test using [`de-red-node-test-helper`](https://www.npmjs.com/package/node-red-node-test-helper).
Can we use Jest to test node?
---
### Author:  [@dceejay](https://discourse.nodered.org/u/dceejay)
#### Post date: [11 July 2019 08:21 UTC](https://discourse.nodered.org/t/can-we-use-jest-for-unit-test/13154/2 "2019-07-11T08:21:05Z")
We've not tried it, but please be our guest and try it for us. Feedback would be welcome.
---
### Author:  [@knolleary](https://discourse.nodered.org/u/knolleary)
#### Post date: [11 July 2019 10:45 UTC](https://discourse.nodered.org/t/can-we-use-jest-for-unit-test/13154/3 "2019-07-11T10:45:59Z")
You can use whatever you want. There is nothing tied to mocha in the test helper - it just provides a convenient way to start/stop the runtime with a test config.
---
### Author:  [@kakyoism](https://discourse.nodered.org/u/kakyoism)
#### Post date: [9 December 2022 09:41 UTC](https://discourse.nodered.org/t/can-we-use-jest-for-unit-test/13154/4 "2022-12-09T09:41:17Z")
I gave it a try and got stumbled upon async loading
```nohighlight
$ jest
FAIL test/flow.test.js
Dummy Node
✓ should be loaded (22 ms)
✕ should make payload lower case (6 ms)
● Dummy Node › should make payload lower case
TypeError: Attempted to wrap log which is already wrapped
39 | { id: "n2", type: "helper" }
40 | ];
> 41 | helper.load(targetNode, flow, function () {
| ^
42 | var n2 = helper.getNode("n2");
43 | var n1 = helper.getNode("n1");
44 | n2.on("input", function (msg) {
at checkWrappedMethod (node_modules/sinon/lib/sinon/util/core/wrap-method.js:64:21)
at wrapMethod (node_modules/sinon/lib/sinon/util/core/wrap-method.js:135:13)
at Function.spy (node_modules/sinon/lib/sinon/spy.js:180:16)
at Sandbox.spy (node_modules/sinon/lib/sinon/sandbox.js:383:35)
at NodeTestHelper.load (node_modules/node-red-node-test-helper/index.js:178:53)
at Object.load (test/flow.test.js:41:12)
--------------
Error: Stack Trace for original
at extendObjectWithWrappedMethods (node_modules/sinon/lib/sinon/util/core/wrap-method.js:169:34)
at wrapMethod (node_modules/sinon/lib/sinon/util/core/wrap-method.js:157:5)
at Function.spy (node_modules/sinon/lib/sinon/spy.js:180:16)
at Sandbox.spy (node_modules/sinon/lib/sinon/sandbox.js:383:35)
at NodeTestHelper.load (node_modules/node-red-node-test-helper/index.js:178:53)
at Object.load (test/flow.test.js:25:12)
Test Suites: 1 failed, 1 total
Tests: 1 failed, 1 passed, 2 total
Snapshots: 0 total
Time: 1.044 s, estimated 2 s
Ran all test suites.
```
here is my test code
```nohighlight
"use strict";
var should = require('should');
var helper = require("node-red-node-test-helper");
const fs = require('fs');
const Path = require('path');
var targetNode = require("../node.js");
helper.init(require.resolve('node-red'));
beforeAll(function (done) {
helper.startServer(done);
});
afterAll( (done) => {
helper.unload().then(function() {
helper.stopServer(done);
});
});
describe('Dummy Node', () => {
// this.timeout(10000);
it('should be loaded', (done) => {
var flow = [{ id: "n1", type: "dummy", name: "dummy node" }];
helper.load(targetNode, flow, function () {
var n1 = helper.getNode("n1");
try {
expect(n1.name).toEqual('dummy node');
done();
} catch (e) {
done(e)
}
});
});
});
```