带有私有字段的void方法的单元测试-线路覆盖率

Question

I have the following code in my void method in ClassUnderTest class

public void doSomething(){

    A a = new A();
    a.setAb("b");
    a.setAc("c");

    persistantObject.commitObj(a);
}

I know how to write a passing JUnit, however, I can't figure out how to get a 100% line coverage.

I've attempted the following

@Mock
private PersistantObject mockPersistantObject;
public void testDoSomething(){

    EasyMock.createMock(this);
    ClassUnderTest classUnderTest = new ClassUnderTest();
    ReflectionTestUtils.setField(classUnderTest, "persistantObject", mockPersistantObject);

    A a = new A();
    a.setAb("b");
    a.setAc("c");

    mockPersistantObject.commitObj(a);
    EasyMock.expectLastCall();

    EasyMock.replay(this);
    classUnderTest.doSomething();
    ...
    EasyMock.verify(this);
}

Answer 1

UnitTesting is not about line coverage.

UnitTesting is about requirement coverage.

Line coverage is just a tool to get a feeling about how much of the requirements already implemented might be covered.

So don't care too much about the LoCs covered by your test but look for behavior in your requirements , that needs a certain behavior of your cut and check if that is covered by a test.

---

Furthermore UnitTests do not care about LoCs for another reason: The LoCs are subject to change during refactoring and evolving the application. Therefore any effort you may do to increase the line coverage will either lead to breaking test or prevent the required changes (depending on your confidence in your tests and or your skills). But Unittests should only fail if the behavior changes, not the code implementing it.