Spring Consider introducing @AutowiredTest to automatically autowire each field in a test class

Considering that SF since 4.3 @Autowired is not necessary to be declared explicitly in a contructor when in the class exists only one constructor.

Consider the following

@ActiveProfiles({"pre-prod","cache"})
@SpringJUnitConfig(classes={AppConfig.class})
@DisplayName("Testing Multiple 'reporte' Test Methods")
@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
class CientificoServiceReporteTests {

    @Autowired
    private CientificoService cientificoService;

    @Autowired
    private ConfigurableApplicationContext ctx;

    @Autowired
    private Environment env;

    @Test
    @Order(1)
    @DisplayName("Testing Reporte - 'findById'")
    void reporteFindByIdTest() {
            ...
    }

       ...

}

It works as expected. Furthermore I know that is not wise use @Autowired in an instance variable for a business classes such as @Service and @Repository, but is valid for @Configuration and Test classes.

Could you consider in "create" something like this:

@AutowiredTest
@ActiveProfiles({"pre-prod","cache"})
@SpringJUnitConfig(classes={AppConfig.class})
@DisplayName("Testing Multiple 'reporte' Test Methods")
@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
class CientificoServiceReporteTests {

    private CientificoService cientificoService;
    private ConfigurableApplicationContext ctx;
    private Environment env;

    @Test
    @Order(1)
    @DisplayName("Testing Reporte - 'findById'")
    void reporteFindByIdTest() {
            ...
    }

        ...

}

Observe that is not used @Autowired anymore in the instance variables but is declared @AutowiredTest at class level.

The point is: if a Test class has at class level @AutowiredTest declared then Spring Framework should apply Autowiring automatically for each instance variable declared. This idea brought me a student and he did mention it is possible in Python.

What do you think?

Comment From: sbrannen

Hi @manueljordan,

Thanks for the suggestion.

Unfortunately, introducing such an annotation/mechanism could likely lead to issues for use cases where a test class contains other fields that cannot be autowired from a Spring ApplicationContext -- for example, @TempDir fields, fields that track some form of state within the test class, mocks, etc.

In light of that, we do not plan to add such a feature.

However, with JUnit Jupiter based tests, you always have the option of autowiring the constructor.

For example, you could write your example as follows.

@SpringJUnitConfig(AppConfig.class)
class CientificoServiceReporteTests {

    private final CientificoService cientificoService;
    private final ConfigurableApplicationContext ctx;
    private final Environment env;

    @Autowired
    CientificoServiceReporteTests(CientificoService cientificoService, 
            ConfigurableApplicationContext ctx) {
        this.cientificoService = cientificoService;
        this.ctx = ctx;
        this.env = ctx.getEnvironment();
    }

    @Test
    @DisplayName("Testing Reporte - 'findById'")
    void reporteFindByIdTest() {
        // ...
    }

    // ...

}

And if you annotate your test class with @TestConstructor(autowireMode = ALL) or change the default test constructor autowire mode to ALL, you can omit @Autowired on the constructor.

See the section on Constructor Injection in the reference manual for further details.

Comment From: manueljordan

Hello @sbrannen

Thanks for the reply and feedback. Understood. I am going to check this set of annotations to see some samples in action.