Java By Comparison

Expected Before Actual Value

class CruiseControlTest {

    @Test
    void setPlanetarySpeedIs7667() {
        CruiseControl cruiseControl = new CruiseControl();

        cruiseControl.setPreset(SpeedPreset.PLANETARY_SPEED);

        Assertions.assertEquals(cruiseControl.getTargetSpeedKmh(), 7667);
    }
}

The test above looks correct, doesn’t it? You can see its structuring into different parts, it uses assertEquals() to compare the results, and it has a meaningful name. You need to look closely to find a problem in the code.

It gets more obvious when you run the test and the assertion fails. If that happens, you’ll get a message like this one:

expected: <1337> but was <7667>

The message tells you that the two values in the assertEquals() method are different. ...