Overview

Here's a demo unit test reproducing the issue: https://github.com/romainmoreau/spy-demo/blob/master/src/test/java/com/example/demo/DemoMockTest.java

The issue happens with Spring Boot 3.4.0-RC1, but it was working with Spring Boot 3.4.0-M3.

Here's the full stack trace: https://github.com/romainmoreau/spy-demo/actions/runs/11532983997/job/32105377666#step:4:2342

It works with Spring Boot 3.4.0-RC1 if Spring Framework is downgraded to 6.2.0-RC1.

Related Issues

• Test bean override support should only override singletons #33602
• Spring Framework 6.2.0-RC2 no longer creates a spy for @MockitoSpyBean #33803