I'm running some tests on my Ruby code, but the method I'm testing calls a function in an external library responsible for sending push notifications. I want the calls it makes to be 'faked', so they don't actually get called. It'd also be helpful if they could return a standard response, or yield with a standard response. Is there any way to do this?
Sure you can fake calling methods in Ruby tests. What you are looking for is creating so called mock code. It is entirely possible to return anything you want from such mock code.
You can create an identifier in Ruby which shadows another one - so for example you can create your own function shadowing one already existing in a library.
Google for the items written above in bold or ask more specific question, if needed.
The VCR gem makes it very easy to save your test suite's HTTP interactions and run them deterministically. That would be my suggested approach.
You can also, as others have pointed out, stub the method you are calling and manually specify its response. If you were using rspec, this would mean to add a line above the HTTP call in the test. Something along the lines of:
allow(Pusher).to receive(:message).and_return( "An object of your liking" )
Related
I was wondering if it is possible to call a method directly from the XAE environment (online) for testing purposes. This would vastly reduce the amount of time to quickly test a function.
As an example; now I would write for each method:
IF bTestMethod THEN
fbFunctionBlock.method(parameters);
bTestMethod := FALSE;
END_IF
It would be nice to be able to call the function directly from the header within the online XAE interface by (for example) using a pragma like properties.
Maybe this functionality is already available that I'm not aware of? What would be the best / fastest way to test methods?
Thanks in advance,
Wouter
It would be nice to be able to call the function directly from the header within the online XAE interface by (for example) using a pragma like properties.
There is a pragma for calling methods remotely {attribute 'TcRpcEnable'}. But I don't know of any way to call it directly from XAE.
In the past I have used this pragma to test a method against an online 'calculator' with the help of node-red and this ADS node.
You can also add the method with the pragma to an opc-ua server. And use a client like UA-Expert to call the method manually.
Once you added the pragma, there are multiple ways to call it and test it over Ads. For many languages is a library available to make the ads calls. You can build a small test script, or a full test framework.
Like already mentioned in other answers, there is also a unit-testing library available to test code inside the controller without the need for extra software and pragma's: TcUnit
Maybe this functionality is already available that I'm not aware of?
Not that I'm aware of. There is no way to just call a function/method from XAE, because all the code is executed cyclically. So you need some way to 'activate' the function.
What would be the best / fastest way to test methods?
Make unit tests for individual functions and function blocks. Or you can make a digital twin to simulate machine behavior.
I'm writing some tests for a Spring WebFlux application and I'm trying to mock a scenario where a request doesn't have a body. I reached for the built-in MockServerRequest, figuring I'd use the built-in mock over making my own. It does allow constructing an instance without a body, but my tests are failing as all of its methods for extracting the body contain an assertion that the body is not null. This doesn't seem to line up with how an actual request would behave. It's totally possible to make a request with no body. I'd also say it's reasonable to have code that checks to see if there's a body, as backed up by the existence of methods like awaitBodyOrNull (I'm using Kotlin).
Am I missing/misunderstanding something here? I'm constructing my mock by just doing MockServerRequest.builder().build() (the methods under test don't care about anything other than the body). Is this class perhaps not actually meant to be used on its own? I'm not finding anyone else asking about this so I feel like I must be overlooking something.
For now I'll work around this by just making my own mock.
MockServerRequest.Builder expects you to give it a body already wrapped in a Mono. It doesn't do any wrapping for you. So mocking an empty request is done with MockServerRequest.builder().body(Mono.empty<TestDto>()).
I have some tests in ruby which call some framework methods and classes. The problem I'm facing, is that some methods can throw exceptions, since they contact services not in my control. I want in the teardown method of the test to actually have the result of the test (success, failed with XXX), so I can do some stuff based on that. Is there a way I can do that (different from wrapping the whole test in a begin/rescue block) ?
A code example of what you're trying to test might help. But depending on the framework API you're working with you can stub out the method that tries to contact the service, that would raise the exception. If you are calling one method that you are trying to test, and it also raises an exception (not very DRY/SRP code) then it makes it tricky. If that's the case, can either do a begin/rescue around that method call, or stub out the call to that larger method. The problem with doing the latter is it can obscure the value of your test more.
Maybe this is counterproductive, I don't know, but right now I am in need of a debugger in IntelliJ that are aware of EasyMock mocks and especially what the mocks methods actually returns.
For example, I have a transport interface ITransport, which has some methods that had to be mocked, and where I only want some of methods returning something. E.g.
ITransport myTransport = createMock(ITransport.class);
I want myTransport.getID() to return a mocked ID 10.
expect(myTransport.getID()).andReturn(10);
With ID 10 I want a method to be invoked once,
expect(myTransport.publish(any(...)));
expectLastCall.once();
Something in the transport class breaks and myTransport isn't called, and my test fails. Know I just want to step through the code with the debugger to check why my test fails. So I add a breakpoint to verify the values of the mocked myTransport object. But they all say "null", even the ID. So I assume, with some brief investigation, that the cause of this is the EasyMock mock class, it doesn't really update the object with value (which sounds reasonable) and instead returns the mocked value at runtime when the method is called.
So, are there any mock aware debuggers for IntelliJ that lets me see which value the method will eventually return.
Yes, and before I receive responses saying that "The debugger is not required if you write unit tests for everything", I just want to state that I know about that. And this is legacy code, or at least code that wasn't written with testing in mind.
This may not be what you're looking for... but it feels like the problem is more on the debugging approach.
A mock object is really just that - a mock - meaning it's a fake empty object that doesn't do anything unless you specifically tell it. When your debugger inspects the mock object, it won't find any values that you did not specifically program it to return. It's not meant to hold values.
EasyMock has an argument capture feature, but since you just want it for debugging, this is probably the wrong approach. Mockito has a spying feature that could be suitable for what you want, but it would involve additional mock-programming statements.
I would say the easiest approach would be to implement your own ITransport just for use in your test class. That way you can implement getID() to always return 10 and put in an assert statement inside your publish(). And you can implement whatever other methods you need in order to capture additional data for debugging purposes. And you get to keep this test-only ITransport for either shared use or future debugging needs.
Indeed, the methods are mocked but the internal implementation of the class is left to itself.
Usually, you don't need to know what is returned since you're the one who recorded it in the first place.
You can also evaluate myTransport.getID() in your debugger. But doing this will consume the expectations.
However, it seems like a good idea to be able to list the all current pending expectations on a mock. And maybe to have a peek function. You can request such features on the EasyMock bug tracker: http://jira.codehaus.org/browse/EASYMOCK
First of all, I have to say, I'm new to mocking. So maybe I'm missing a point.
I'm also just starting to get used to the TDD approach.
So, in my actual project I'm working on a class in the business layer, while the data layer has yet to be deployed. I thought, this would be a good time to get started with mocking. I'm using Rhino Mocks, but I've come to the problem of needing to know the implementation details of a class before writing the class itself.
Rhino Mocks checks if alle the methods expected to be called are actually called. So I often need to know which mocked method is being called by the tested method first, even though they could be called in any order. Because of that I'm often writing complicated methods before I test them, because then I know already in which order the methods are being called.
simple example:
public void CreateAandB(bool arg1, bool arg2) {
if(arg1)
daoA.Create();
else throw new exception;
if(arg2)
daoB.Create();
else throw new exception;
}
if I want to test the error handling of this method, I'd have to know which method is being called first. But I don't want to be bugged about implementation details when writing the test first.
Am I missing something?
You have 2 choices. If the method should result in some change in your class the you can test the results of your method instead. So can you call CreateAandB(true,false) then then call some other method to see if the correct thing was created. In this situation your mock objects will probably be stubs which just provide some data.
If the doaA and doaB are objects which are injected into your class that actually create data in the DB or similar, which you can't verify the results of in the test, then you want to test the interaction with them, in which case you create the mocks and set the expectations, then call the method and verify that the expectations are met. In this situation your mock objects will be mocks and will verify the expected behaviour.
Yes you are testing implementation details, but your are testing the details of if your method is using its dependencies correctly, which is what you want to test, not how it is using them, which are the details you are not really interested in.
EDIT
IDao daoA = MockRepository.GenerateMock<IDao>(); //create mock
daoA.Expect(dao=>dao.Create); //set expectation
...
daoA.VerifyExpectations(); //check that the Create method was called
you can ensure that the expectations happen in a certain order, but not using the AAA syntax I believe (source from 2009, might have changed since,EDIT see here for an option which might work), but it seems someone has developed an approach which might allow this here. I've never used that and can't verify it.
As for needing to know which method was called first so you can verify the exception you have a couple of choices:
Have a different message in your exception and check that to determine which exception was raised.
Expect a call to daoA in addition to expecting the exception. If you don't get the call to daoA then the test fails as the exception must have been the first one.
Often times you just need fake objects, not mocks. Mock objects are meant to test component interaction, and often you can avoid this by querying the state of SUT directly. Most practical uses of mocks are to test interaction with some external system (DB, file system, webservice, etc.), and for other things you should be able to query system state directly.