JUnit: how to avoid “no runnable methods” in test utils classes

118
votes

I have switched to JUnit4.4 from JUnit3.8. I run my tests using ant, all my tests run successfully but test utility classes fail with "No runnable methods" error. The pattern I am using is to include all classes with name *Test* under test folder.

I understand that the runner can't find any method annotated with @Test attribute. But they don't contain such annotation because these classes are not tests. Surprisingly when running these tests in eclipse, it doesn't complain about these classes.

In JUnit3.8 it wasn't a problem at all since these utility classes didn't extend TestCase so the runner didn't try to execute them.

I know I can exclude these specific classes in the junit target in ant script. But I don't want to change the build file upon every new utility class I add. I can also rename the classes (but giving good names to classes was always my weakest talent :-) )

Is there any elegant solution for this problem?

10
javaantjunittesting
Does your tests work in Eclipse/NetBeans/your favourite IDE? – guerda
I use eclipse. Actually there is no problem there, somehow eclipse doesn't try to run these classes. I wonder how? – LiorH
I don't know if we understood your question. Please re-read your question and probably add some more information. – guerda
@guerda: The question seems pretty clear to me. His Ant task is finding classes which don't contain tests, because the filter is picking up the utility class. Hence my answer, which I still believe is entirely relevant. – Jon Skeet
LiorH: Thanks for clarification, so my answer is waste :) – guerda

10 Answers

51
votes

Assuming you're in control of the pattern used to find test classes, I'd suggest changing it to match *Test rather than *Test*. That way TestHelper won't get matched, but FooTest will.

142
votes

Annotate your util classes with @Ignore. This will cause JUnit not to try and run them as tests.

86
votes

My specific case has the following scenario. Our tests 

public class VenueResourceContainerTest extends BaseTixContainerTest

all extend 

BaseTixContainerTest

and JUnit was trying to run BaseTixContainerTest. Poor BaseTixContainerTest was just trying to setup the container, setup the client, order some pizza and relax... man.

As mentioned previously, you can annotate the class with 

@Ignore

But that caused JUnit to report that test as skipped (as opposed to completely ignored). 

Tests run: 4, Failures: 0, Errors: 0, Skipped: 1

That kind of irritated me.

So I made BaseTixContainerTest abstract, and now JUnit truly ignores it.

Tests run: 3, Failures: 0, Errors: 0, Skipped: 0
38
votes

To prevent JUnit from instantiating your test base class just make it 

public abstract class MyTestBaseClass { ... whatever... }

(@Ignore reports it as ignored which I reserve for temporarily ignored tests.)

19
votes
  1. If this is your base test class for example AbstractTest and all your tests extends this then define this class as abstract
  2. If it is Util class then better remove *Test from the class rename it is MyTestUtil or Utils etc.
14
votes

Be careful when using an IDE's code-completion to add the import for @Test.

It has to be import org.junit.Test and not import org.testng.annotations.Test, for example. If you do the latter, you'll get the "no runnable methods" error.

8
votes

Ant now comes with the skipNonTests attribute which was designed to do exactly what you seem to be looking for. No need to change your base classes to abstract or add annotations to them.

4
votes

What about adding an empty test method to these classes? 

public void avoidAnnoyingErrorMessageWhenRunningTestsInAnt() {
    assertTrue(true); // do nothing;
}
3
votes

In your test class if wrote import org.junit.jupiter.api.Test; delete it and write import org.junit.Test; In this case it worked me as well.

0
votes

I was also facing a similar issue ("no runnable methods..") on running the simplest of simple piece of code (Using @Test, @Before etc.) and found the solution nowhere. I was using Junit4 and Eclipse SDK version 4.1.2. Resolved my problem by using the latest Eclipse SDK 4.2.2. I hope this helps people who are struggling with a somewhat similar issue.