使用Spring Boot Gradle插件时，尝试使用某些类型的扩展功能模拟接口会产生错误。没有Spring Boot Gradle插件，模拟就可以工作。
我发现的两种情况是带有lambda参数的扩展功能和集合上的扩展功能。可能还有更多，但是那些正在影响我们的项目。
例如：
interface InterfaceWithExtensionFunctionWithLambda {
fun String.extensionFunction(performAction: () -> String): String {
return performAction()
}
}
@Test
fun `Can mock interface with extension function with lambda`() {
Mockito.mock(InterfaceWithExtensionFunctionWithLambda::class.java)
}
给出的错误是：
org.mockito.exceptions.base.MockitoException:
Mockito cannot mock this class: interface com.example.demo.InterfaceWithExtensionFunctionOnCollection.
Mockito can only mock non-private & non-final classes.
If you're not sure why you're getting this error, please report to the mailing list.
Java : 1.8
JVM vendor name : Oracle Corporation
JVM vendor version : 25.181-b13
JVM name : OpenJDK 64-Bit Server VM
JVM version : 1.8.0_181-8u181-b13-0ubuntu0.18.04.1-b13
JVM info : mixed mode
OS name : Linux
OS version : 4.15.0-33-generic
Underlying exception : java.lang.IllegalArgumentException: object is not an instance of declaring class
at com.example.demo.MockingTests.Can mock interface with extension function on collection(MockingTests.kt:29)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$ForTypeArgument.resolve(TypeDescription.java:3083)
at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$Delegator$Chained.resolve(TypeDescription.java:2868)
at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$ForTypeArgument.resolve(TypeDescription.java:3056)
at net.bytebuddy.description.type.TypeDescription$Generic$AnnotationReader$Delegator.asList(TypeDescription.java:2822)
at net.bytebuddy.description.type.TypeDescription$Generic$OfNonGenericType$ForLoadedType.getDeclaredAnnotations(TypeDescription.java:3450)
at net.bytebuddy.implementation.attribute.AnnotationAppender$ForTypeAnnotations.apply(AnnotationAppender.java:639)
at net.bytebuddy.implementation.attribute.AnnotationAppender$ForTypeAnnotations.onNonGenericType(AnnotationAppender.java:620)
at net.bytebuddy.implementation.attribute.AnnotationAppender$ForTypeAnnotations.onNonGenericType(AnnotationAppender.java:333)
at net.bytebuddy.description.type.TypeDescription$Generic$OfNonGenericType.accept(TypeDescription.java:3270)
at net.bytebuddy.implementation.attribute.AnnotationAppender$ForTypeAnnotations.onParameterizedType(AnnotationAppender.java:601)
at net.bytebuddy.implementation.attribute.AnnotationAppender$ForTypeAnnotations.onParameterizedType(AnnotationAppender.java:333)
at net.bytebuddy.description.type.TypeDescription$Generic$OfParameterizedType.accept(TypeDescription.java:4372)
at net.bytebuddy.implementation.attribute.MethodAttributeAppender$ForInstrumentedMethod.apply(MethodAttributeAppender.java:183)
at net.bytebuddy.implementation.attribute.MethodAttributeAppender$Compound.apply(MethodAttributeAppender.java:425)
at net.bytebuddy.dynamic.scaffold.TypeWriter$MethodPool$Record$ForDefinedMethod$WithBody.applyAttributes(TypeWriter.java:617)
at net.bytebuddy.dynamic.scaffold.TypeWriter$MethodPool$Record$ForDefinedMethod$WithBody.applyBody(TypeWriter.java:609)
at net.bytebuddy.dynamic.scaffold.TypeWriter$MethodPool$Record$ForDefinedMethod.apply(TypeWriter.java:528)
at net.bytebuddy.dynamic.scaffold.TypeWriter$Default$ForCreation.create(TypeWriter.java:4167)
at net.bytebuddy.dynamic.scaffold.TypeWriter$Default.make(TypeWriter.java:1653)
at net.bytebuddy.dynamic.scaffold.subclass.SubclassDynamicTypeBuilder.make(SubclassDynamicTypeBuilder.java:183)
at net.bytebuddy.dynamic.scaffold.subclass.SubclassDynamicTypeBuilder.make(SubclassDynamicTypeBuilder.java:163)
at net.bytebuddy.dynamic.DynamicType$Builder$AbstractBase.make(DynamicType.java:2669)
at net.bytebuddy.dynamic.DynamicType$Builder$AbstractBase$Delegator.make(DynamicType.java:2771)
at org.mockito.internal.creation.bytebuddy.SubclassBytecodeGenerator.mockClass(SubclassBytecodeGenerator.java:128)
at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator$1.call(TypeCachingBytecodeGenerator.java:37)
at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator$1.call(TypeCachingBytecodeGenerator.java:34)
at net.bytebuddy.TypeCache.findOrInsert(TypeCache.java:137)
at net.bytebuddy.TypeCache$WithInlineExpunction.findOrInsert(TypeCache.java:344)
at net.bytebuddy.TypeCache.findOrInsert(TypeCache.java:159)
at net.bytebuddy.TypeCache$WithInlineExpunction.findOrInsert(TypeCache.java:353)
at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.mockClass(TypeCachingBytecodeGenerator.java:32)
at org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker.createMockType(SubclassByteBuddyMockMaker.java:71)
at org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker.createMock(SubclassByteBuddyMockMaker.java:42)
at org.mockito.internal.creation.bytebuddy.ByteBuddyMockMaker.createMock(ByteBuddyMockMaker.java:25)
at org.mockito.internal.util.MockUtil.createMock(MockUtil.java:35)
at org.mockito.internal.MockitoCore.mock(MockitoCore.java:69)
at org.mockito.Mockito.mock(Mockito.java:1895)
at org.mockito.Mockito.mock(Mockito.java:1804)
... 23 moreo.Mockito.mock(Mockito.java:1895)
at org.mockito.Mockito.mock(Mockito.java:1804)
... 23 more
I have created a very simple sample project with tests showing this error, which is on Github here.
有人知道此问题的解决方案吗？如果是错误，最好在哪里报告问题？目前，我已经通过将功能重写为扩展功能来解决此问题，但是最好找到合适的解决方案。