coverage

gistfile1.java

/*
 * Original requirement:
 * if a > b, return 1, if a == b return 0, if a < b return -1
 */

/* 
 * Day 1
 * Paul comes in and does untested code which has a bug
 */
 
 class UntestedClass {
   public int compare(int a, int b) {
    if (a > b) {
      return -1;
    }
    
    if (a == b) {
      return 0
    }
    
    return 1;
   }
 }
 
 
 /*
  * Day 2
  * Nelson comes in and checks the code coverage.
  * OH NOES! THERE ARE NO TESTS!
  */
  
class UntestedClassTest {
  
  private UntestedClass theClass = new UntestedClass();
  
  @Test
  public void testAgtB throws Exception {
    assertThat(theClass.compare(5, 3), is(-1));
  }
  @Test
  public void testAeqB throws Exception {
    assertThat(theClass.compare(3, 3), is(0));
  }
  @Test
  public void testAltB throws Exception {
    assertThat(theClass.compare(3, 5), is(1));
  }
}

// Now the code is covered, and the bug looks like a requirement for future developers...