ManRow ManRow - 13 days ago 5
Java Question

Mockito swallows up stack trace?

Why does Mockito swallow up stack traces? For example, if I have a

public class Foo
{
public void foo()
{
bar();
}

public void bar()
{
baz();
}

public void baz()
{
throw new RuntimeException();
}
}


and a test such as

public class MockTest
{
@Test
public void test()
{
Mockito.spy(new Foo()).foo();
}
}


the exception thrown always looks like


java.lang.RuntimeException
at Foo.baz(Foo.java:17)
at MockTest.test(MockTest.java:11)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)



** So, where is all the stuff between

Foo.baz(Foo.java:17)
MockTest.test(MockTest.java:11)



?

(The example provided here is a just a simplification -- I'm dealing with a lot more indirections, classes, and so forth. I can't have Mockito swallowing up the critical parts of a partial mock stack trace...)

Answer

YES, mockito cleans stacktraces !

The piece of code at work StackTraceFilter

There are different ways to disable that

  • Since Mockito 1.10.10, provide your own StackTraceCleanerProvider via the mockito extension mechanism (create a resource file mockito-extensions/org.mockito.plugins.StackTraceCleanerProvider with the qualified name of your implementation)

  • Override the cleansStackTrace method in a custom IMockitoConfiguration, look there for more information.