JUnit @Test expected annotation not working

Question

I've got the following test:

@Test(expected = IllegalStateException.class)
public void testKey() {
    int key = 1;
    this.finder(key);
}

But JUnit reports, that the test fails, although it throws — as expected — an IllegalStateException.

Do I have to configure something else to make this run?

I run the test now with

@RunWith(Suite.class)
@SuiteClasses(Test.class)
public class TestSuite {

}

like in this question, but am still not getting the desired result.

And when I remove the test prefix I'm still getting an error.

I gotta say that I run these tests with Eclipse, but it's configured to use the JUnit 4 Runner.

Maybe you are inadvertently running the test with JUnit 3. Does the test class extend TestCase? What happens when you change the name of the test method so that it no longer starts with `test`? — Peter Niederwieser, Apr 05 '11 at 10:13
When the test's name doesn't start with `test`, I get the message `junit.framework.AssertionFailedError: No tests found in MyClass` — , Apr 05 '11 at 10:34
Well then it's clear - you are mixing JUnit 3 and JUnit 4 features, which doesn't work. Either write your test in JUnit 3 style, or in JUnit 4 style. — Peter Niederwieser, Apr 05 '11 at 10:40
Might be you're importing something other than `org.junit.jupiter.api.Test`. — aderchox, Feb 24 '21 at 18:53

score 51 · Accepted Answer · 2011-04-07T06:31:28.600

51

The problem was, that the class in which the test was nested was an extension of TestCase. Since this is JUnit 3 style, the annotation didn't work.

Now my test class is a class on its own.

edited Apr 07 '11 at 06:31

answered Apr 05 '11 at 11:06

score 10 · Answer 2 · answered Dec 09 '14 at 18:53

10

@RunWith(JUnit4.class)
public class MyTestCaseBase extends TestCase

I also had problems with @Test(expected = ...) annotation when I extended TestCase class in my base test. Using @RunWith(JUnit4.class) helped instantly (not an extremely elegant solution, I admit)

answered Dec 09 '14 at 18:53

pmar_x86

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You should not extend TestCase anymore with JUnit4+. – Mark Renouf Sep 25 '17 at 13:57

Dipak · Answer 3 · 2018-03-15T04:30:58.250

7

i tried this one, and work perfectly as expected.

public class SampleClassTest {
    @Test(expected = ArithmeticException.class )
    public void lost(){
        this.lost(0);
    }
    private void lost(int i) throws ArithmeticException {
        System.out.println(3/i);
    }
}

also ensure that junit4 is added as dependancy, @ (annotations) are new feature in junit 4.

edited Mar 15 '18 at 04:30

answered Nov 20 '12 at 11:26

Dipak

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score 6 · Answer 4 · answered Jan 02 '14 at 11:01

6

I faced same issue, solution is simple "Don't extends TestCase class"

answered Jan 02 '14 at 11:01

guesst

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score 3 · Answer 5 · edited Jan 14 '18 at 12:45

3

I had the same problem I just changed my imports statements. I removed :

import org.junit.jupiter.api.Test;

import junit.framework.TestCase;

and added :

import org.junit.Test;

And it worked fine for me.

edited Jan 14 '18 at 12:45

Nawrez

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answered Jan 14 '18 at 12:23

dhakre

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score 3 · Answer 6 · answered Apr 05 '11 at 10:10

3

No, this JUnit test should work as it is - there is nothing more needed on this side.

What makes you sure that the test throws an IllegalStateException? Is it possible that it gets wrapped into another exception of different type?

Please post the exact failure message from JUnit.

As @duffymo suggested, it is easy to verify what (if any) exception the test really throws.

answered Apr 05 '11 at 10:10

Péter Török

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JUnit's message: `java.lang.IllegalStateException: ... MyErrorMessage ..` – Apr 05 '11 at 10:37
Yes, it's possible for the exception to be wrapped into another one, but in that case you should assert the _wrapper_ one, and never the other. – Powerslave Sep 07 '14 at 11:06

score 2 · Answer 7 · answered Apr 05 '11 at 10:09

This looks correct to me.

Check your assumptions. Are you sure it throws the exception? If what you say is true, removing the expected from the annotation should make it fail.

I'd be stepping through the code with a debugger to see what's going on. I'll assume you have an IDE that will do so, like IntelliJ.

score 0 · Answer 8 · answered Apr 05 '11 at 10:12

0

Just tested this under JUnit4: this DO work, test completes successfully. Look if it is a IllegalSelectorException or such.

answered Apr 05 '11 at 10:12

Alex Abdugafarov

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JUnit @Test expected annotation not working

8 Answers8

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