Software Testing · Quiz 1 · Sep 2024

**1. Enumerate prime paths:** [1,2,3,4], [1,2,6,7], [1,5,7], [2,3,4,2], [3,4,2,3], [3,4,2,6,7], [4,2,3,4], [5,5]. **2. Count:** Three cycle rotations, one self-loop, and four maximal noncyclic paths give eight requirements. **Answer: C — 8.** A: **Incorrect:** The derived count is 8, not 6. B: **Incorrect:** The derived count is 8, not 7. C: **Correct:** The derived count is 8, which matches this option. D: **Incorrect:** The derived count is 8, not 9.

**1. Check short-branch requirements:** Edge-pair coverage requires both [1,2,6] and [1,5,7]. A looping path cannot replace these consecutive edge pairs. **2. Check loop requirements:** The longer cycle tests cover [2,3,4], [3,4,2], [4,2,3], [4,2,6]; the self-loop test covers [1,5,5], [5,5,5], [5,5,7]. Both C and D cover all requirements. **Answer: C, D — Sets C and D.** A: **Incorrect:** It lacks consecutive pair [1,2,6]. B: **Incorrect:** It lacks consecutive pair [1,5,7]. C: **Correct:** It includes both nonloop branch pairs and all loop pairs. D: **Correct:** The extra loop iteration preserves complete edge-pair coverage.

**1. Count decisions:** Bubble sort contains two for-loop conditions and one if comparison: three decisions. **2. Add the base path:** \(V=3+1=4\). **Answer: B — 4.** A: **Incorrect:** The derived count is 4, not 3. B: **Correct:** The derived count is 4, which matches this option. C: **Incorrect:** The derived count is 4, not 5. D: **Incorrect:** The derived count is 4, not 6.

**1. Identify the closed excursion:** In P, the segment [3,4,2,3] leaves node 3 and returns to node 3. It is a closed side excursion, while the other listed segments do not return to their starting node. **2. Interpret the intended question:** A is the listed segment having the shape of a sidetrip, rather than an excursion returning at a different successor node. **Answer: A — [3,4,2,3].** **Convention note:** The wording is imprecise: the stated prime path [1,2,5,6] is not toured with sidetrips because P never traverses edge 2→5. Also, formal sidetrip touring implies the weaker node-order detour criterion. A is the intended closed-excursion answer, not proof of the literal “sidetrip but not detour” claim. A: **Correct:** It is a closed excursion returning to its start. B: **Incorrect:** It ends at 6 rather than returning to 3. C: **Incorrect:** It ends at 4 rather than returning to 1. D: **Incorrect:** It ends at 5 rather than returning to 2.

**1. Assign parity states:** State 1 is (even zeros, even ones); state 2 is (odd, even); state 4 is (even, odd); state 3 is (odd, odd). Reading 0 toggles zero parity, while reading 1 toggles one parity. **2. Identify acceptance:** Only state 1 is accepting, so both symbol counts must be even. **Answer: B — It accepts all strings that have even number of 0s and even number of 1s..** A: **Incorrect:** This ends in nonaccepting state 3. B: **Correct:** Both even counts return to accepting state 1. C: **Incorrect:** This ends in nonaccepting state 2. D: **Incorrect:** This ends in nonaccepting state 4.

**1. Identify the concept:** Level 3 in the testing-maturity model focuses on reducing software-usage risk through cooperation between developers and testers. **Answer: D — Level-3.** A: **Incorrect:** Level 0 equates testing with debugging. B: **Incorrect:** Level 1 emphasizes demonstrating that the program works. C: **Incorrect:** Level 2 emphasizes showing failures. D: **Correct:** Level 3 introduces the stated cooperative risk-reduction objective. E: **Incorrect:** Level 4 is a broader quality discipline; Level 3 is the minimum here.

**1. Enter the outer branch:** The initial values x=a and y=b require \(a-b<0\). **2. Substitute the assignment:** Inside that branch y becomes \(ab\). Reaching the error then requires \(ab>100\), so both conditions are needed. **Answer: C — \(a-b<0\land ab>100\).** A: **Incorrect:** It ignores the outer branch and the changed value of y. B: **Incorrect:** The inner condition uses updated y=ab, not original b. C: **Correct:** It combines the outer condition with the correct updated inner condition. D: **Incorrect:** This negates the required inner condition.

**1. Identify the concept:** Both modules exchange information by reading and writing the same memory block. This is a shared-memory interface. **Answer: B — Shared memory interface.** A: **Incorrect:** The scenario does not describe invoking the other module’s procedure. B: **Correct:** The common readable/writable memory block is shared memory. C: **Incorrect:** No exchange of discrete messages is described. D: **Incorrect:** Shared memory directly matches the mechanism.

**1. Identify the concept:** Big-bang integration combines the available real components at once, avoiding the temporary drivers and stubs needed to replace missing components during incremental integration. **Answer: D — Big bang.** A: **Incorrect:** Missing lower-level components normally require stubs. B: **Incorrect:** Missing higher-level callers normally require drivers. C: **Incorrect:** It combines approaches that use drivers and stubs. D: **Correct:** Real components are integrated together rather than replaced by integration scaffolding.

**1. Identify the concept:** A decision vertex has at least two outgoing alternatives. Such a branching singleton qualifies as a DD-path. **Answer: D — ≥ 2.** A: **Incorrect:** Out-degree zero identifies an exit, not a decision. B: **Incorrect:** Fewer than two outgoing edges do not form a branch. C: **Incorrect:** One outgoing edge provides no choice. D: **Correct:** At least two outgoing edges make it a decision vertex.

**1. Identify the concept:** A value crossing a call boundary comes from the last definition before the call or return and reaches its first relevant use in the receiving module or after the call. **Answer: C — (1) last definitions, (2) first uses.** A: **Incorrect:** An earlier definition may already have been overwritten. B: **Incorrect:** Neither the earliest definition nor the last use identifies the boundary transfer. C: **Correct:** Last definitions and first uses identify the inter-procedural transfer. D: **Incorrect:** The first use is the receiving boundary event, not the last use.

**1. Identify the concept:** White-box testing derives tests from internal code or structure. That approach can be used at unit, integration and system levels; acceptance and beta testing are normally driven by external requirements and user behaviour. **Answer: A, B, C — Unit testing; Integration testing; System testing.** A: **Correct:** Individual units can be tested using internal branches and paths. B: **Correct:** Interactions can be tested using internal call and data-flow structure. C: **Correct:** Whole-system tests can also target internal structure. D: **Incorrect:** Acceptance testing normally verifies externally specified user requirements. E: **Incorrect:** Beta testing normally relies on user operation rather than source-code analysis.

**1. Check edge coverage:** The paths [1,2,5,6] and [1,2,3,4,3,5,6] collectively traverse every edge and visit every node. **2. Identify missing pairs:** [2,3,5] and [4,3,4] are valid consecutive edge pairs but occur in neither test. Hence edge-pair coverage is not achieved. **Answer: B, C — Node and edge coverage; no edge-pair coverage.** A: **Incorrect:** Edge coverage is achieved as well. B: **Correct:** Both nodes and edges are covered. C: **Correct:** Every edge is covered but some consecutive pairs are missing. D: **Incorrect:** The valid pairs [2,3,5] and [4,3,4] are absent.

**1. Apply subsumption:** C2 subsumes C1, so satisfying the stronger criterion C2 implies C1. C3 subsumes C2 and therefore C1 by transitivity. **2. Apply to the test sets:** T2 and T3 necessarily satisfy the weaker C1 requirements represented by T1; the reverse implications are not guaranteed. **Answer: B, D — T2 satisfies C1; T3 satisfies C1.** **Convention note:** The question loosely says one test set “satisfies” another; the precise implication concerns the coverage criteria those sets satisfy. A: **Incorrect:** Satisfying weaker C1 does not imply stronger C2. B: **Correct:** C2 subsumes C1. C: **Incorrect:** Satisfying C2 does not imply stronger C3. D: **Correct:** C3 subsumes C2, which subsumes C1.

**1. Trace search:** The loop starts at index 1, so it skips the 20 at index 0. Searching for 20 returns −1, making test 3’s equality-to-zero assertion fail. **2. Check the absent key:** Searching for 100 returns the integer −1, boxed as a non-null Integer for assertNull. Thus test 4 fails. Searches for 10 and 50 return the expected indices 1 and 4. **Answer: C, D — testCase3() and testCase4().** A: **Incorrect:** The method finds 10 at index 1. B: **Incorrect:** The method finds 50 at index 4. C: **Correct:** The skipped index 0 makes search(20) return −1. D: **Correct:** The integer result −1 is not null.

**1. Read the path guards:** Taking a→b requires \(x\ge y\); taking b→e requires \(x<z\). Hence the path condition is \(y\le x<z\). **2. Evaluate inputs:** (20,20,30) and (20,10,30) satisfy both guards. (10,10,10) and (30,20,30) fail the strict x<z guard. **Answer: B, C — (20,20,30) and (20,10,30).** A: **Incorrect:** 10<10 is false. B: **Correct:** 20≥20 and 20<30 are both true. C: **Correct:** 20≥10 and 20<30 are both true. D: **Incorrect:** 30<30 is false.

**1. Enumerate definition-clear simple paths:** From node 1’s definition to the two predicate-use edges: [1,2,3] and [1,2,4]. From node 4’s definition to print(x): [4,5]. **2. Count:** There are three distinct DU-path sequences. Paths from node 1 through node 4 to node 5 are not definition-clear for x. **Answer: B — 3.** A: **Incorrect:** The derived count is 3, not 2. B: **Correct:** The derived count is 3, which matches this option. C: **Incorrect:** The derived count is 3, not 4. D: **Incorrect:** The derived count is 3, not 5.