mockito: Mock enum with methods fails on Java 17

The following fails on Java 17 and works on 11 and 16:

public enum ExampleEnum {
    TEST {
        public String retrieve() {
            return "test";
        }
    };

    public String getValue() {
        return "21";
    }
}

public class Container {
    private ExampleEnum exampleEnum;
    public Container(ExampleEnum exampleEnum) {
        this.exampleEnum = exampleEnum;
    }

    public String retrieveValue() {
        return exampleEnum.getValue();
    }
}

@ExtendWith(MockitoExtension.class)
public class ExampleEnumTest {

    @Mock
    private ExampleEnum exampleEnum;

    @Test
    public void testEnumWithMethods() {
        Container container = new Container(exampleEnum);
        Mockito.when(exampleEnum.getValue()).thenReturn("42");
        assertEquals("42", container.retrieveValue());
    }
}

On 17 it gives the following error:

org.mockito.exceptions.base.MockitoException:

Mockito cannot mock this class: class com.example.ExampleEnum.

If you're not sure why you're getting this error, please report to the mailing list.


Java               : 17
JVM vendor name    : Oracle Corporation
JVM vendor version : 17-ea+24-2164
JVM name           : OpenJDK 64-Bit Server VM
JVM version        : 17-ea+24-2164
JVM info           : mixed mode, sharing
OS name            : Linux
OS version         : 4.19.76-linuxkit


You are seeing this disclaimer because Mockito is configured to create inlined mocks.
You can learn about inline mocks and their limitations under item #39 of the Mockito class javadoc.

Underlying exception : org.mockito.exceptions.base.MockitoException: Could not modify all classes [interface java.lang.constant.Constable, class java.lang.Object, interface java.lang.Comparable, interface java.io.Serializable, class java.lang.Enum, class com.example.ExampleEnum]
Caused by: org.mockito.exceptions.base.MockitoException: Could not modify all classes [interface java.lang.constant.Constable, class java.lang.Object, interface java.lang.Comparable, interface java.io.Serializable, class java.lang.Enum, class com.example.ExampleEnum]
Caused by: java.lang.UnsupportedOperationException: class redefinition failed: attempted to change the class NestHost, NestMembers, Record, or PermittedSubclasses attribute

The complete code example can be found here: https://github.com/johanjanssen/JavaUpgrades/tree/main/java17

It can be build with Docker for instance with (17 can be replaced with 11 and 16): docker build -t javaupgrades -f …\Dockerfile --build-arg JDK_VERSION=17 .

Is there some way I can work around this issue?