It is possible for Y to cover more branches in a program than X Introduction to Software Testing Question 1 Consider a program P and two test suites X and Y for P Test suite X covers set of branches Q in the program while test suite Y covers set of branches R in the program Suppose Q is a proper subset of R Q R Which of the below statements are necessarily true A Whenever a test in Y reaches a statement some test in X also reaches that statement B Whenever a test in X reaches a statement some test in Y also reaches that statement C Test suite Y has strictly higher path coverage than test suite X D Test suite Y has strictly higher branch coverage than test suite X Answer B D C is not a correct answer without covering more paths through the program Question 2 Consider the Java function void copy int src int dst int N for int i 0 i N i dst i src i Which of the below predicates is the function s weakest possible precondition that prevent any null pointer or array out of bounds exceptions from being thrown NOTE The expression X Y is read X implies Y It is equivalent to X OR Y A N 0 src null dst null N src length N dst length B N 0 src null dst null N src length dst length src length C N 0 src null dst null N src length N dst length D N 0 src null dst null N src length dst length src length Answer C Question 3 Consider a test suite consisting of three deterministic tests T1 T2 T3 for a correct program P Since P is correct it passes all the three tests Suppose we have three mutants M1 M2 M3 of P such that M1 fails T1 and T2 M2 fails none and M3 fails T2 and T3 Let M P denote that M and P are equivalent Likewise let M P denote that they are NOT equivalent a Could it be possible that M1 P Justify your answer Answer No b Mutation analysis will report M2 to the tester since it does not fail any test in the test suite Which of the following actions are plausible for the tester to take given this information A Determine if M2 P and if so devise a new test case T4 on which M2 passes but P fails B Determine if M2 P and if so then ignore M2 C Determine if M2 P and if so devise a new test case T4 on which P passes but M2 fails D Determine if M2 P and if so ignore M2 Answer C D