[Right]-BICEP: Are the Results Right?

Our tests should first validate that the code produces the expected results. The arithmetic-mean test below demonstrates that the ScoreCollection class produces the correct mean of 6 given the numbers 5 and 7.

@Test
public void answersArithmeticMeanOfTwoNumbers() {
   ScoreCollection collection = new ScoreCollection();
   collection.add(() -> 5);
   collection.add(() -> 7);
   
   int actualResult = collection.arithmeticMean();
   
   assertThat(actualResult, equalTo(6));
}

Happy path test

• We might bolster such a test by adding more numbers to ScoreCollection or by trying larger numeric values. Regardless, such tests remain in the realm of happy path tests—positive cases that reflect a portion of an end-user goal for the software (it could be a tiny portion!). If our code provides the right answer for these cases, the end-user will be happy.
• A happy path test represents one answer to an important question: