Question

This is more of a design question.

Suppose you have a method like this (as an example):

if (x == 5) {
  c = 1;
} else {
 if (z != 2) {
  b = 6;
} else {
   a = 3;
}

Do you think it’s best practice to have a junit for each possible branch? Ie, testx5, test xnot5znot2, testxnot5z2, etc, or something like:

void testMethod() {
// x is 5
test/assert code;

// x not 5, z not 2
test/assert code;

// x not 5, z is 2
test/assert code

// etc
}

EDIT: Just to be clear, my goal is complete code coverage. I just want to know opinions on whether I should make a new test for each branch or combine them in one test. Thank you for your input.

Answer 1

The JUnit FAQ seems to indicate that it is better to have more tests with fewer assertions, if only because JUnit will only report the first assertion failure in a test method. With one method, if you broke the x = 5 case, you’d have no way to tell if any of the x != 5 cases were still working.