軟件測試復習題及答案

1、復習題1.Below is one faulty program. It includes a test case that results in failure. Answer the following questions about the program.(20)(a) Identify the fault.(b) If possible, identify a test case that does not execute the fault.(c) If possible, identify a test case that executes the fault, but does

2、 not result in an error state.(d) If possible identify a test case that results in an error, but not a failure. Hint: Dont forget about the program counter.(e) For the given test case, identify the first error state. Be sure to describe the complete state.(f) Fix the fault and verify that the given

3、test now produces the expected output.(a) The for-loop should search high to low:for (int i=x.length-1; i = 0; i-) (b) All inputs execute the fault - even the null input.(c) If the loop is not executed at all, there is no error. If the loop is executed only once, high-to-low and low-to-high evaluati

4、on are the same. Hence there is no error for length 0 or length 1 inputs.Input: x = 3Expected Output: -1Actual Output: -1(d) There is an error anytime the loop is executed more than once, since the values of index i ascend instead of descend.Input: x = 1, 0, 3Expected Output: 1Actual Output: 1(e) Th

5、e first error state is when index i has the value 0 when it should have a value at the end of the array, namely x.length-1. Hence, the first error state is encountered immediately after the assignment to i in the for-statement if there is more than one value in x.Input: x = 0, 1, 0Expected Output: 2

6、Actual Output: 0First Error State:x = 0, 1, 0i = 0PC = just after i= 0;(f ) See (a)4. Answer questions (a)(d) for the graph defined by the following sets: N = 1, 2, 3, 4，N0 = 1，Nf = 4，E = (1, 2), (2, 3), (3, 2), (2, 4)(a) Draw the graph.(b) List test paths that achieve node coverage, but not edge co

7、verage.(c) List test paths that achieve edge coverage, but not edge Pair coverage.(d) List test paths that achieve edge pair coverage.(a)Omitted.(b) For this program, this is not possible. All test paths must begin at node 1, visit node 2, and, eventually, end at node 4. Any test path that visits no

8、de 3 also visits both edge (2; 3) and edge (3; 2).(c) T = 1; 2; 3; 2; 4Note that the edge pair 3; 2; 3 is not toured by the single test path given.(d) T = 1; 2; 4; 1; 2; 3; 2; 3; 2; 45. A graph is defined by the sets of nodes, initial nodes, final nodes, edges, and defs and uses. Each graph also con

9、tains a collection of test paths. Answer the following questions about each graph.(a) Draw the graph.(b) List all of the du-paths with respect to x. (Note: Include all du-paths, even those that are subpaths of some other du-path).(c) For each test path, determine which du-paths that test path tours.

10、 For this part of the exercise, you should consider both direct touring and sidetrips. Hint: A table is a convenient format for describing this relationship.(d) List a minimal test set that satisfies all defs coverage with respect to x. (Direct tours only.) Use the given test paths.(e) List a minima

11、l test set that satisfies all uses coverage with respect to x. (Direct tours only.) Use the given test paths.(f) List a minimal test set that satisfies all du-paths coverage with respect to x.(Direct tours only.) Use the given test paths.(a)Omitted.6. The graph in Figure 3 was used as an example for

12、 prime test paths. Add appropriate edge labels to the graph, then derive and simplify the path expressions. Next add edge weights of 1 for non-cycle edges and 5 for cycle edges. Then compute the maximum number of paths in the graph and the minimum number of paths to reach all edges. This graph has 2

13、5 prime paths. Briefly discuss the number of prime paths with the maximum number of paths and consider the effect of varying the cycle weight on the maximum number of paths.(15) Fig 37. Use functions f to answer the following question. 8. How are faults and failures related to testing and debugging?

14、Faults are problems in the code, failures are incorrect external events. Depending on which of Beizers levels you are working in, testing is the process of trying to cause failures or to show that they occur at an acceptable rate. In contrast, debugging is a diagnostic process where, given a failure

15、, an attempt is made to find the associated fault.錯誤和失敗是如何相關的測試和調試?缺點是代碼中的問題,失敗是不正確的外部事件。取決于你正在進行的Beizer的等級,測試是一個過程,試圖造成失敗或表明他們發(fā)生在一個可接受的速度。相比之下,調試是一種診斷過程中,給定一個失敗,試圖找到相關的故障9. For what do testers use automation? What are the limitations of automation?Automation can help in many areas, most often to relieve the tester from repetitive, mechanical tasks. Checking of testing criteria can be automated through instrumentation, which allows a higher level of testing to be performed. Automation will always run into undecidable problems, such as in