I’m looking to use the mockConstruction method from the org.mockito.Mockito class in my unit tests. I have a scenario where I need to mock the construction of a specific class within my code. How can I properly implement this in my test setup? Any examples or best practices would be greatly appreciated.
Hey there! To use mockConstruction, you’ll first set up a mock for the class you want to test. Let’s say you have a class Foo; you’d use Mockito.mockConstruction(Foo.class) in your test. This allows you to specify how new instances of Foo behave during the test. You can also verify constructor invocations. Make sure your Mockito version is 3.5.0 or higher as it’s a newer feature. Happy testing!
I’ve been working with mockConstruction lately, and it’s super handy! If you’re working with a legacy codebase, mockConstruction helps control object creation for testing. Start by calling Mockito.mockConstruction(YourClass.class) in your setup method. You can add settings with MockitoSettings. Don’t forget to verify interactions and reset the mocks to avoid test pollution. It’s excellent for seamlessly testing without altering constructors!
Using mockConstruction can streamline your tests. Suppose you want a controlled environment for a class Bar, initiate it with Mockito.mockConstruction(Bar.class, (mock, context) -> {}). This ‘context’ lets you programmatically define behavior for the mock instance. Remember, it’s crucial in situations where dependency injection isn’t feasible. Always keep an eye on your constructor parameters to ensure the mock behaves as expected during the tests.