I am trying to test a function in one of my component which consists following two lines:
this.rzp1 = new Razorpay(orderDetails);
this.rzp1.open();
I am trying to understand how to mock Razorpay in my test cases for this function.
This is how I am declaring Razorpay in my component:
export declare var Razorpay: any;
I have already tried various methods like:
var stub = sinon.createStubInstance(MyConstructor)
Any leads will be helpful.
Why not use jasmine's built in spy facility instead of relying on another library (sinon)?
In your before each block, you can do something like this:
beforeEach(() => {
jasmine.spyOnAllFunctions(Razorypay.prototype);
Razorypay.prototype.open.and.returnValue('foo');
});
You can find more information about spyOnAllFuntions in the documentation.
Related
How would one test that a piece of custom middleware is actually called from a standard HTTP event?
ie. The middleware is called from:
MyController.js
router.get('/some/endpoint', [myMiddleware()], (req, res, next) => {
// Code to do whatever here
});
The middleware itself can be defined as:
MyMiddleware.js
module.exports = () => {
// Middleware code in here
}
My quest is to check that the middleware is called once from my unit test, but I cannot find documentation around this.
MyTest.test.js
it('Should return whatever from GET call', () => {
return request(app).get('/some/endpoint')
.expect(200)
.expect(res => {res.body.should.deep.equal(bodyValue)});
// How would I place code in here to check that MyMiddleware is called?
// ie. sinon.assert.calledOnce(MyMiddleware)
});
I have thought about using Sinon's spy, but I can't think of how to hook into the middleware... My attempt was this:
const mwSpy = sinon.spy(require('path to middleware file'));
sinon.assert(calledOnce(mwSpy));
The usual way of going about this is splitting this into two tests, an integration test and a unit test.
Will the middleware I specified in the router.get call end up being called when someone hits this endpoint?
Does my middleware do the right thing?
The first part is basically testing that the Express API is doing what the documentation says. That's not what unit tests are for (this was tagged unit-testing), but since you are already using HTTP requests to test the endpoint, I guess that's not what you are after anyway: you are basically creating verification tests for your system.
You could still test the Express routing without HTTP, though, as I detail in the answer to this question, concerning how to test the router programmatically (faster tests, no http), but less just stick to what you have.
So the basic question is: "My quest is to check that the middleware is called once from my unit test". You don't seem to concern yourself with whether the middleware is doing the right thing or not, just that it's called, which calls for the question on whether we should test the middleware or the layer using the middleware.
In both cases, you need to find a way of injecting a test spy. Either you write a small utility method that will inject that spy: function setMiddleware(module){ middleware = module; } or you use some tooling like proxyquire. See this tutorial on Sinon's homepage for background.
I would just do this (in the test code):
it('Should return whatever from GET call', () => {
var middlewareFake = sinon.fake();
// I am assuming it's the actual app object you are referencing below in the request(app) line
var app = proxyquire('../app/index.js', { './my-middleware': middlewareFake });
//
return request(app).get('/some/endpoint')
.expect(200)
.expect(res => {
res.body.should.deep.equal(bodyValue)
expect(middlewareFake).was.called;
});
});
I have a simple Observable piping from another Observable that I want to test.
const loginState$ = messageBusObservables.loginState$.pipe(
startWith({ isLoggedIn: false })
pluck('isLoggedIn'),
distinctUntilChanged()
)
messageBusObservables is an object of observables. Where loginState$ is an Observable.
In my tests, I thought I would easily be able to mock the './messageBus' module like this: (how the module is imported is irrelevant, but import preferred)
import { of } from 'rxjs'
import './messageBus'
jest.mock('./messageBus', () => ({
loginState$: of({ isLoggedIn: true }),
}))
However, Jest throws the error:
babel-plugin-jest-hoist: The module factory of jest.mock() is not allowed to reference any out-of-scope variables.
Invalid variable access: of
I have tried, putting it in a jest.fn() I have tried extracting of({ isLoggedIn: true }) to a variable. But I keep getting the same error from jest.
So how can I mock the input into my Observables using Jest? I'll run into the same problem with other observables using .merge, .zip etc.
It needs to be a real observable that is the input of my other observables. I just want to mock the value with something like of() rather than mocking an object, with a method on it, that returns an object with a .pipe method etc. (I don't want to mock the functionality of an Observable). I want to pass it a real observable with a value set in my unit test.
I also need these mocks to be dynamic. So the mock from 1 assertion can be different from the mock in the next assertion. (clearing them with something like a beforeEach)
EDIT:
I also tried to use babel-plugin-rewire to mock this module, this worked fine in the *.test.js file where I was mocking it. But in the actual file no matter what I set the export to using rewire, it always got imported as the original Observable.
the reason you are getting this message:
babel-plugin-jest-hoist: The module factory of jest.mock() is not allowed to reference any out-of-scope variables. Invalid variable access: of
is because jest automatically hoists calls to jest.mock so that they happen before the imports.
You have two options to get around this default behaviour, the simple way is to use jest.doMock which is NOT hoisted:
jest.doMock('./messageBus', () => ({
loginState$: of({ isLoggedIn: true }),
}))
Alternatively, you can prefix all the variables referenced inside the mock factory passed to jest.mock with "mock":
const mockMessageBus = {
loginState$: of({ isLoggedIn: true }),
}
jest.doMock('./messageBus', () => mockMessageBus)
(note that you are responsible for ensuring all mock variables referenced in the factory function are in scope when jest.mock is called)
You're close.
You are trying to mock the module by passing a module factory as the second parameter to jest.mock. The main constraint of that approach is that the module factory must be completely self-contained and "is not allowed to reference any out-of-scope variables".
Referencing of from rxjs in the module factory (as you have found) breaks that constraint and causes the error you are seeing.
Fortunately there are other ways to mock modules.
From what I can see of your code it looks like the easiest approach would be to create a Manual Mock of the messageBus module.
Create a __mocks__ folder in the same directory as messageBus.js and create the mock (also called messageBus.js) within the __mocks__ folder.
__mocks__/messageBus.js will look something like this:
import { of } from 'rxjs'
export default {
loginState$: of({ isLoggedIn: true })
}
Then tell Jest you want to use the manual mock within your test by calling
jest.mock('messageBus');
at the top of your test file.
That call is hoisted by Jest and ensures that any code that imports messageBus during the test will get the mocked module.
New to testing and React Redux, so I may be conflating a few issues here. I will only present one example, but I have tried many different combinations of mount(), shallow(), instance(), stub, spy and more.
Given a component, where setFooData() updates redux state and Foo.props.data:
const mapDispatchToProps = (dispatch, props) => ({
setFooData(fooId, data) {
dispatch(Actions.setFooData(fooId, data));
},
});
...
return (
<div fooId={this.props.fooId}>
<Foo {...fooProps}/>
</div>
);
I would like to write some tests around the conditions under which setFooData() is called, namely conditions in lifecycle methods like componentDidMount() and componentWillReceiveProps().
Because setFooData() involves server calls and more, and because these tests merely concern the view layer and how the component renders as a result of Foo.props.data being set eventually by setFooData(), setFooData() seems like a good candidate for stub.
Therefore, Enzyme's shallow(), rather than mount(), seems appropriate, correct? In any case, when I try to stub setFooData():
let wrapper = return shallow(<Foo {...props}/>);
let stub = sinon.stub(wrapper.instance(), 'setFooData');
I receive the error:
Attempted to wrap undefined property setFooData as function
Upon inspection, wrapper.instance() yields an object where setFooData() is indeed not defined, but according to other examples, I would think it should be.
Furthermore, setFooData() does exist on wrapper.instance().selector.props, and while let stub = sinon.stub(wrapper.instance().selector.props, 'setFooData'); avoids the error, when I inspect the object setFooData() =/= stub, and the function is not called as per the test.
When I use mount() instead,
let wrapper = mount(<Provider store={store}><Foo {...props}/></Provider>);
let componentDidMountSpy = sinon.spy(Foo.prototype, 'componentDidMount');
let componentWillReceivePropsSpy = sinon.spy(Foo.prototype, 'componentWillReceiveProps');
expect(componentDidMountSpy.called).to.be.true; //passes
expect(componentWillReceivePropsSpy.called).to.be.true; //passes
expect(stub.called).to.be.true; //fails
I receive a different error that appears related to the body of setFooData(), so setFooData() is called but the function is not actually stubbed to prevent its real body from being executed.
Thanks for any help to clarify my understanding.
I think you're taking the hardest path. You should test your component in isolation, not the connected one. If you test the connected component you're making an integration test and double testing that connect indeed works. That's already tested in react-redux for you.
Instead, test your action creators by themselves in unit tests.
Then, export your component as named export without connecting and use the default export for the connect version.
That way you can simply import the pure-React version and pass anything you want as props, in order to make easy assertions afterwards.
If you need to specifically test that something happens in those lifecycle methods, you can call those methods from the instance:
const fakeActionCreator = sinon.spy()
const subject = mount(<MyComponent doSomething={ fakeActionCreator } />)
subject.instance().componentDidMount()
assert.equal(fakeActionCreator.callCount, 1)
I'm trying to unit test my controllers in Laravel 5, but have serious issues wrapping my head around it. It seems as I have to trade the great short-hand functions and static classes for dependency injected equivalents if I actually want to do isolated unit testing.
First off, what I see in the documentation as "Unit testing", is not unit testing to me. It seems more like functional testing. I can not test a controller function isolated, as I will have to go through the entire framework, and will need to actually seed my database if I have any code interacting with my database.
So, in turn, I want to test my controllers isolated of the framework. This is however proving to be quite difficult.
Let's look at this example function (I've kept out some parts of this function for the sake of the question):
public function postLogin(\Illuminate\Http\Request $request)
{
$this->validate($request, [
'email' => 'required|email', 'password' => 'required',
]);
$credentials = $request->only('email', 'password');
if (Auth::attempt($credentials, $request->has('remember')))
{
return redirect()->intended($this->redirectPath());
}
}
Now, the problem arises in the final lines. Sure, I can mock the Request instance that's sent to the function, that's no issue. But how am I going to mock the Auth class, or the redirect function? I need to rewrite my class/function with dependency injection like this:
private $auth;
private $redirector;
public function __construct(Guard $auth, \Illuminate\Routing\Redirector $redirector)
{
$this->auth = $auth;
$this->redirector = $redirector;
}
public function postLogin(\Illuminate\Http\Request $request)
{
$this->validate($request, [
'email' => 'required|email', 'password' => 'required',
]);
$credentials = $request->only('email', 'password');
if ($this->auth->attempt($credentials, $request->has('remember')))
{
return $this->redirector->intended($this->redirectPath());
}
}
And I end up with a convoluted unit test, full of mocks:
public function testPostLoginWithCorrectCredentials()
{
$guardMock = \Mockery::mock('\Illuminate\Contracts\Auth\Guard', function($mock){
$mock->shouldReceive('attempt')->with(['email' => 'test', 'password' => 'test'], false)->andReturn(true);
});
$redirectorMock = \Mockery::mock('\Illuminate\Routing\Redirector', function($mock){
$mock->shouldReceive('intended')->andReturn('/somePath');
});
$requestMock = \Mockery::mock('\Illuminate\Http\Request', function($mock){
$mock->shouldReceive('only')->with('email', 'password')->andReturn(['email' => 'test', 'password' => 'test']);
$mock->shouldReceive('has')->with('remember')->andReturn(false);
});
$object = new AuthController($guardMock, $redirectorMock);
$this->assertEquals('/somePath', $object->postLogin($requestMock));
}
Now, if I had any more complex logic that would, for example, use a model, I'd have to dependency inject that as well, and mock it in my class.
To me, it seems like either, Laravel isn't providing what I want it to do, or my testing logic is flawed. Is there any way I can test my controller functions without getting out-of-control testing functions and/or having to depedency inject standard Laravel classes, available to me anyways in my controller?
You shouldnt be trying to unit test controllers. They are designed to be functional tested via calling them through the HTTP protocol. This is how controllers are designed, and Laravel provides a number of framework assertions you can include in your tests to ensure they work as expected.
But if you want to unit test the application code contained within the controller, then you should actually consider using Commands.
Using Commands allows you to extracte the application logic from your controller into a class. You can then unit test the class/command to ensure you get the results expected.
You can then simply call the command from the controller.
In fact the Laravel documentation tells you this:
We could put all of this logic inside a controller method; however, this has several disadvantages... it is more difficult to unit-test the command as we must also generate a stub HTTP request and make a full request to the application to test the purchase podcast logic.
If I use sinon with typescript then how do I cast the sinon mock to an instance of my object?
For instance a SinonMock would be returned but my controller under test may require a specific service passed in to its constructor.
var myServiceMock: MyStuff.MyService = <MyStuff.MyService (sinon.mock(MyStuff.MyService));
controllerUnderTest = new MyStuff.MyController(myServiceMock, $log);
Can sinon be used with Typescript?
Sinon can create a stub based on a constructor quite easily if, instead of mock, you use the createStubInstance method.
An example using mocha, chai, sinon and sinon-chai, could look like this:
import * as sinon from 'sinon';
import * as chai from 'chai';
// ... imports for the classes under test
const expect = chai.expect;
const sinonChai = require("sinon-chai");
chai.use(sinonChai);
describe('MyController', () => {
it('uses MyService', () => {
let myService = sinon.createStubInstance(MyStuff.MyService),
controller = new MyStuff.MyController(myService as any, ...);
// ... perform an action on the controller
// that calls myService.aMethodWeAreInterestedIn
// verify if the method you're interested in has been called if you want to
expect(myService.aMethodWeAreInterestedIn).to.have.been.called;
});
});
I've published an article, which you might find useful if you'd like to learn more about the different test doubles and how to use them with Sinon.js.
Hope this helps!
Jan
You may need to use an <any> type assertion to make the type wide before you narrow it to your specific type:
var myServiceMock: MyStuff.MyService =
<MyStuff.MyService> <any> (sinon.mock(MyStuff.MyService));
Just to clarify one behaviour of sinon - although you pass in MyStuff.MyService, whatever you pass to the mock method is only used to provide better error messages.
If you want the mock to have methods and properties, you need to add them.
If you want automatically created fakes, you can grab the FakeFactory from tsUnit, which creates a fake version with some default values that you can opt to override - in JavaScript this is pretty easy stuff (plus by not using too much mock functionality, you can ensure you are testing behaviour rather than implementation).
Example use of FakeFactory:
var target = tsUnit.FakeFactory.getFake<RealClass>(RealClass);
var result = target.run();
this.areIdentical(undefined, result);
In Typescript this can be achieved by using sinon.createStubInstance and SinonStubbedInstance class.
Example:
let documentRepository: SinonStubbedInstance<DocumentRepository>;
documentRepository = sinon.createStubInstance(DocumentRepository);
Now you have a full intellisense for working with all stubbed methods of this class.
Example Arrange:
documentRepository.delete.resolves({deletedCount: 1});
documentRepository.update.throws(error);
Example Assert:
sinon.assert.calledOnce(documentRepository.update);
There is only one place where you would need to perform type casting and that is the initiallization of the class you want to unit test.
Example:
documentsController =
new DocumentsController(
userContext,
documentRepository as unknown as DocumentRepository);
Hope this will help.
More on this article.
Use ts-sinon.
It lets you:
stub objects
stub interfaces