Spring Framework 6.2.0-RC2 no longer creates a spy for `@MockitoSpyBean`

[JKatzwinkel]

Upgrading from Spring Boot 3.4.0-M3 (Spring Framework 6.2.0-RC1) to Spring Boot 3.4.0-RC1 (Spring Framework 6.2.0-RC3) breaks my use of a @MockitoSpyBean of the form doReturn(results).when(spyBean).method(argumentMatchers...).

That form is the one recommend by Mockito.

The error thrown says Argument passed to when() is not a mock!: https://github.com/JKatzwinkel/tla-es/actions/runs/11541063711/job/32122614536?pr=382#step:9:188 .

This problem did not occur with Spring Boot 3.4.0-M3 (Spring Framework 6.2.0-RC1).

This is where the spy (operations) gets stubbed:

https://github.com/JKatzwinkel/tla-es/blob/dependabot/gradle/spring-boot-bf23beedc8/src/test/java/tla/backend/service/SentenceServiceTest.java#L99-L103

        doReturn(hits).when(operations).search(
            any(org.springframework.data.elasticsearch.core.query.Query.class),
            eq(SentenceEntity.class),
            any()
        );

Please let me know if you need further information or if this is not an issue with spring boot. Thanks!

[sbrannen]

Hi @JKatzwinkel,

Thanks for reporting the issue you've encountered.

Please let me know if you need further information or if this is not an issue with spring boot.

It's difficult to assess based on the complexity of the tla-es project you've referenced.

Out of curiosity, why did you switch from a @MockBean for ElasticsearchOperations in the original tla-es project to a @MockitoSpyBean in your fork?

In any case, please provide a minimal sample application that reproduces the problem (that we can download and run), preferably one that does not require the use of Lombok or Docker containers.

Cheers,

Sam

[sbrannen]

@JKatzwinkel, I experimented with your application, and after some hacking... it appears that your use of @MockitoSpyBean may work with 6.2 snapshots.

In other words, this may effectively be a:

• duplicate of #33800

So, before you take the time to create a minimal sample application, can you please try with 6.2.0-SNAPSHOT for Spring Framework dependencies such as org.springframework:spring-test?

If you need help setting up Gradle to use snapshots, this wiki page should prove useful.

Cheers,

Sam

[JKatzwinkel]

thank you very much for the investigating and good news! I will look into that and let you know!

[JKatzwinkel]

@sbrannen adding org.springframework:spring-test:6.2.0-SNAPSHOT to the test dependencies does indeed make the error disappear! I am very grateful for your quick response and gathering insights without me having to come up with a minimal sample application, and of course for the fix in https://github.com/spring-projects/spring-framework/commit/81d89f478aa2441ecfa90907ba21b7cc20152059 !

I am looking forward to the next release containing the patched bean factory post processor! Thanks again!

---

Out of curiosity, why did you switch from a @MockBean for ElasticsearchOperations in the original tla-es project to a @MockitoSpyBean in your fork?

Using a @MockitoBean instead of a spy leads to failed dependency resolution during application context loading, because some other autowired spring components down the line also use ElasticsearchOperations in their @PostConstruct hook. They use it for creating Elasticsearch indexes in my fork, whereas in the original tla-es repo, index creation is being done automatically by spring-data-elasticsearch, so their ElasticsearchOperations mock isn't expected to actually do anything.

[sbrannen]

Hi @JKatzwinkel,

@sbrannen adding org.springframework:spring-test:6.2.0-SNAPSHOT to the test dependencies does indeed make the error disappear!

Great! Thanks for trying it out and confirming it solves your problem.

I am very grateful for your quick response and gathering insights without me having to come up with a minimal sample application, and of course for the fix in 81d89f4 !

You're welcome.

I am looking forward to the next release containing the patched bean factory post processor! Thanks again!

That next "release" should be 6.2 GA.

Thanks for clarifying why you switched to @MockitoSpyBean in your fork.

Although there were actually two "bugs" in the Bean Override support regarding FactoryBeans, the fix I pushed for #33800 actually resolved the issue you reported as well. In light of that I am closing this as a:

• Duplicate of #33800