SWE 637 Quiz Number 3
February 17, 2010

Consider the graph:

  N = { A, B, C, D }
  N0 = { A, B }
  Nf = { A }
  E = { (A,B), (B,C), (B,D), (C,A), (D,A) (D,D) }

  t0 = [ A B C A B D A ]
  t1 = [ B C A ]
  t2 = [ B D A B D D D A]
  t3 = [ B C A B D ]

1. Which candiate test path is not, in fact, a test path? Why not?
   Answer: t3 fails to end in a final node.
2. List the test requirements for Edge-Pair Coverage. (You should get 9).
   Answer: The edge pairs are:

          { [A B C],
            [A B D], 
            [B C A], 
            [B D A], 
            [B D D], 
            [C A B], 
            [D A B], 
            [D D A], 
            [D D D] }
   

3. List all of the prime paths. (You should get 9).
   Answer:

          { [A B C A],
            [A B D A],
            [B C A B],
            [B D A B],
            [C A B C],
            [C A B D],
            [D A B C],
            [D A B D],
            [D D]}
   

4. If possible, give a minimal set of test paths (from the given set) that satisfies Edge-Pair Coverage. If not, satisfy to the extent possible, and identify what is missing.
   Answer: t0 by itself tours 5 of the 9 edge pairs. t2 tours the missing 4 edge pairs. Hence T = {t0, t2} satisfies edge-pair and is minimal. There are no other minimal test sets.
5. Consider the prime path [A B D A]. Give a test path (from the given set) that tours this prime path directly. Give a test path (from the given set) that tours this prime path with a sidetrip.
   Answer: Direct tour
   t0 tours the prime path directly.
   Indirect tour
   t2 tours the prime path with the sidetrip [D D D}.
   (It is also true that t0 tours the prime path with the sidetrip [A B C A].)