c# Stubbing a Property get using Rhino Mocks


The 264 spacious and light hotel rooms include newly refurbished standard and executive rooms with city views. We use the latest and greatest technology available to provide the best possible web experience. In this last section, I want to draw your attention to a controversial topic. If you want to use Rhino Mocks to test an application, then you are forced to write your application in a particular way. Some people think this requirement is a virtue since it forces your application to have a testable design. Other people believe that the design of your application should not be dictated by the limitations of a particular tool.

  • You can get the public key for an assembly by using the sn -Tp yourAssembly.dll command in the Visual Studio Command Prompt.
  • Moq also provides a .VerifyAll() method which will validate all of the mocks and stubs you’ve created with .Setup().
  • When performing behavior verification, your test typically does not end with an assert statement.
  • You can either use the nUnit command line tools to run the tests or several good tools that integrate into Visual Studio, such as ReSharper, TestRunner.Net or, my favorite, NCrunch.

When performing behavior verification, your test typically does not end with an assert statement. Instead, the interaction of the objects being tested is verified. Rhino Mocks throws an exception automatically when mock expectations do not meet reality.

The advantage of using a static method is that it saves a line of code when calling the method since you don’t need to instantiate the class before using it. For example, the DataProvider class in Listing 20 calls Logger.Write() in both of its methods. The first test — named BarkTestStrictReplay() — uses CreateMock() to create an instance of Rover. If you don’t make the exact method calls setup in the expectations section, then the test fails when the expectations are played back against reality. The unit test in Listing 11 illustrates how you can create a stub for the IProductRepository interface and setup the stub’s Select() method so that it always returns a fake set of products.

In previous posts on Moq and JustMock Lite I’ve mentioned strict and loose behavior. Sometimes we need to mock out classes or APIs to assert the expected behaviour. Mocking is built in to Spock, we don’t need a separate library or framework for Mock support. If you’re used to other Mocking frameworks you might expect to only be able to mock Java interfaces, but Spock lets us easily create a mock from a concrete class. ;
We mock these dependencies using the GenerateStub call and we pass the fake objects we just created, into the PizzaMaker. These objects we created can be “driven” in many different way but for now, in this test, they are just needed to allow our code to compile.

Providing a Method Implementation / Using the Input Params

The test demonstrates that the DoublePrice() method does, in fact, double the price of the product correctly. Before you can test the method in Listing 8, you need a class that implements the IProduct interface. If you don’t want to do the work to implement the interface at the moment, then you can use Rhino Mocks to create DevOps Outsourcing Services a stub from the interface automatically. The test in Listing 9, once again, takes advantage of the MockRepository.GenerateStub() method to generate a concrete stub from an interface. So if you need to mock a concrete object but have the code use the concrete class methods in places, you can use the PartialMock.

If a method is called unexpectedly, then the mock object will not fail verification and no exception is thrown. CreateMock() – This method of creating a mock object enforces a strict replay of expectations. If a method is called unexpectedly, then the mock object will fail verification and throw an exception. In this test, Rover is created with the DynamicMock() method. This method of creating a mock object allows for looser expectations. Calling the Bark() method a third time, or calling an unexpected method like Fetch(), does not cause the test to fail.

Stubbing a Property get using Rhino Mocks

If you run the test in Listing 14, and the Logger.Log() method is not called with the expected value for CustomerId, then the unit test fails. Notice that the unit test does not contain an assert statement. If expectations do not match reality, Rhino Mocks causes the unit test to fail by raising an ExpectationViolationException exception. When performing behavior verification tests with Rhino Mocks, your test code is divided into two sections.

rhino mocks stub

How can I check that I’m properly interacting with the Oven and passing it the pizza? This is exactly the scope of the method AssertWasCalled. In Rhino Mocks this call is GenerateStub and we use it to generate all the objects that are interacting with our system under test . In our example class, PizzaMaker expose a property, called ReadyForAnotherPizza. In the main project LiviosPizzeria you can find the main class, which we want to test.

When the Select() method is called, the contents of the _fakeProducts field is returned. Another and equally valid reason for using a stub is that you haven’t actually implemented a particular object required for a test. For example, you might want to unit test a method that relies on a DataProvider Why cybersecurity is the ultimate recession-proof industry object, but you have not had a chance to implement the data provider object. In this case, the mock object is acting as a stand-in for the real object so that you can build other objects that depend on the stub. On the one hand, you can use a Mock Object Framework to create stubs.

Stubs vs Mocks

In the end posts, I will go through into the more advance features of Rhino Mocks. Finally, the test in Listing 23 illustrates how you can use Rhino Mocks to perform a behavior verification of the Logger and DataProvider class. Notice that a mock version of the Logger class is created and passed to an actual instance of the DataProvider class.

rhino mocks stub

Mocks are useful for checking calls out of our code, Stubs are useful for providing data or values into the code we’re testing. Mocks are a powerful and useful tool to make sure that the code that we’re testing is calling the APIs that we expect, in the way we expect. The given block also sets up a Polygon with the given renderer, calling the constructor with the numberOfSides and the mocked renderer. Behavior verification verify that these methods are actually called and called in above order. For e.g. in the above Order method of WarehouseOrder class.

Assert that a method is called with a value in an expected state

Methods could return values but it’s all about minimal implementations and consistency. Unlike mocks we’re not trying to test behavior, so we’re not interested in whether a method was called once or a hundred times. DynamicMock() – This method of creating a mock object permits a looser replay of expectations.

The correct output of this program should be “I’m in foo2” – even though “I’m in foo1” coded into foo1, the call to it is intercepted. Change the getForegroundColour method to return the palette’s primary colour. It should fail if we haven’t implemented Automate your container orchestration with Ansible modules for Kubernetes the details for getForegroundColour. It’s good to see the test fail first, it often indicates the test is checking the right thing, even if that right thing hasn’t been implemented yet. Stub object vary their response based on input parameters.

Imagine that you need to test a method that relies on database data. However, you don’t want to access the database when you execute the unit test because accessing the database would be too slow. In this case, you can create a stub method that always returns a hard-coded set of values.

A Guide to Moq for Rhino.Mocks Users

Strict MockA strict mock requires you to provide alternate implementations for each method/property that is used on the mock. So if you’re only wanting to replace some of the functionality , and keep the rest, you’ll want to use this. You can use Rhino Mocks to create stubs for interfaces, abstract classes, and concrete classes. When creating a stub for class methods, the method must be marked as virtual. This last requirement places some significant limitations on what you can stub. You cannot use Rhino Mocks with static or sealed methods (we’ll return to this issue in the last section of this blog entry).

A unit test created for the purposes of Test-Driven Development — a TDD unit test — has additional requirements. A unit test appropriate for TDD unit test should execute very quickly and should not require any application configuration. A unit test enables you to test a single unit of code in isolation.


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