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javaunit-testingjunit5powermockitojunit-jupiter

PowerMockito.whenNew() is not getting mocked and original method is called with junit 5


I am writing Junit jupiter test for project. I am trying to mock new instance creation using mock. but instead of getting mock object i am getting actual object

please see my code below

Main java class

public class TestSubjectClass {
    public String doSomething() {
        Integer number = new Integer(1);
        return internalLogic(number.toString());
}
    }

My test class

@RunWith(PowerMockRunner.class)
@PrepareForTest(TestSubjectClass.class)
class TestSubjectClassTest {
    @Test
    public void mockNewObjectCreation() throws Exception {
        TestSubjectClass testedClass = new TestSubjectClass();
        Integer mockedValue = new Integer(5);
        PowerMockito.whenNew(Integer.class).withAnyArguments().thenReturn(mockedValue);
        String output = testedClass.doSomething();
        assertThat(output, CoreMatchers.containsString("Here is an input: 5"));
  }
 }

My pom.xml

        <dependency>
            <groupId>org.powermock</groupId>
            <artifactId>powermock-module-junit4</artifactId>
            <version>2.0.7</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.powermock</groupId>
            <artifactId>powermock-api-mockito2</artifactId>
            <version>2.0.7</version>
            <scope>test</scope>
        </dependency>    
        <dependency>
            <groupId>org.springframework.session</groupId>
            <artifactId>spring-session-core</artifactId>
        </dependency>

When i run junit 5 test the actual mocking of new instance is not happening . Any clue what i did wrong

Java.lang.assertionerror: Expected: a string containing "Here is an input 5" but was "Here is an input 1"

Error:


Solution

  • I won't analyze or make any comment about this particular test, but note that up to this point there is no PowerMock support for JUnit 5:

    https://github.com/powermock/powermock/issues/830

    So you might want to consider using JUnit 4 for this.