JUnit-DI

Motivation

• This project was an idea picked from sfragis Guice-Junit which enabled DI in fields of test classes in JUnit4, as a custom Runner, So the idea was to enable similar functionality using JUnit5 and the removed restrictions such as , test methods should not have parameters, using this this project will enable you to inject services or stubs as method params in your JUnit5 test

How to use it ?

• Your tests should be running on JUnit5, and you'll need to implement yourself the logic of resolving dependencies as i can't make this choice for your . the demos in the repo might help you get started, demo-cdi uses CDI (Context and Dependency Injection) standard from JAVA EE as a InjectionHandler, and demo-memory uses a simple fixed HashMap to do the resolution .

• You should be familiar with the ServiceLoader api, so you should create a file test/resources/META-INF/services/io.github.chermehdi.junitdi.api.InjectionHandlerProvider and put the fully qualified name of your InjectionHandlerProvider implementation so it get's picked by the ServiceLoader at Runtime

public class InMemoryInjectionHandlerProvider implements InjectionHandlerProvider {
  @Override
  public InjectionHandler createHandler() {
    return new MyInjectionHandler();
  }
}

• Create your implementation

public class MyInjectionHandler implements InjectionHandler {

  // Your implementation 
}

• and now in your tests you just need to add @ExtendWith(InjectionExtension.class) something like :

@ExtendWith(InjectionExtension.class)
class MyTestClass {
  
  @Test
  void testMethod(SomeService service) {
    assertNotNull(service);
  }
}

• or you can use :

@EnableInjection
class MyTestClass {
  
  @Test
  void testMethod(SomeService service) {
    assertNotNull(service);
  }
}

Contribution

• Any bug report or feature request or any kind of contribution is highly appreciated 😃