Page 270 - 《软件学报》2024年第6期

2846 软件学报 2024 年第 35 卷第 6 期

表 1 BPEL 程序主要活动描述

Category Activity Description
Receive The beginning of a business process, responsible for receiving the request messages sent by a client
Reply The end of the business process, responsible for returning the results of the business operation to the client
Basic activity
Assign Assign a parameter under the <from> variable to a parameter under the <to> variable
Invoke Invoke a service corresponding to a partner link and collect the result returned by the service
Sequence Execute each activity within a Sequence in a given order
If Determine whether certain conditions are met to perform a particular operation
Structured While
Determine whether certain conditions are met to enter a loop in an activity
activity (RepeatUntil)
Flow Define the activities that need to be executed in parallel
Scope Define the action scope of an internal activity and provides a common component for the activities within it

1.2 变异分析

变异分析 (也称变异测试) 是一种基于缺陷的软件测试技术 [12,13] , 广泛用于评估测试用例集的充分性以及测试

技术的有效性. 变异分析通过模拟编程人员在软件开发过程中可能出现的一些错误植入故障, 执行测试用例集, 判
断测试用例集揭示这些故障的能力. 测试用例集的故障检测能力可以通过变异得分 [14] 来衡量, 即测试用例集能够
杀死的非等价变异体 (语义上与原程序不一致的变异体) 占所有的非等价变异体的比例.
变异分析基于两个重要的假设 [13] : 熟练程序员假设 (熟练程序员编写出的缺陷代码与正确代码之间只有细微
差别, 仅通过小幅度代码修改即可更正错误) 和耦合效应假设 (若某个测试用例可以检测出简单故障, 那么该测试
用例也有潜力检测出更复杂的故障).
传统变异分析流程如下 [15] : (1) 根据程序语言特征设计一组变异算子; (2) 在原程序上应用变异算子生成大量
变异体; (3) 从变异体集合中识别出等价变异体 (语义上与原程序一致的变异体) 并筛除; (4) 测试剩余变异体, 若执
行结果与原程序结果不一致, 则称该变异体被杀死; 否则, 变异体存活.
1.3 BPEL 变异算子
变异算子定义了将原程序转变为变异体的转换规则, 是实施变异分析的关键. 表 2 总结了常见的 BPEL 程序
算子 [16] , 包括标识符替换、表达式变异、活动变异、异常与事件变异这 4 类.
表 2 BPEL 程序变异算子描述

Category Mutation operator Description
Identifier substitute
ISV Substitute a variable identifier with another one of the same type
mutation
EAA Substitute an arithmetic operator (+ , – , * , /) with another operator
EEU Remove the unary subtraction operator from an expression
ERR Substitute a relational operator (< , > , <= , >= , = , ! =) with another one
ELL Substitute a logical operator (and , or) with another one
ECC Substitute a path operator (/ , //) with another one
ECN Increase or decrease the value of a numeric constant, add or remove a number
Expression mutation
EMD Set the duration to 0, or reduce the duration by half
EMF Set the cut-off time to 0, or reduce the cut-off time by half
EIN Insert XPath format “not” into a logical expression
EIU Insert XPath format unary subtraction into an arithmetic expression
EAP Substitute an expression with its absolute value
EAN Substitute an expression with its negative absolute value
CFA Replace an activity with an exit activity
Override criterion CDE Apply decision coverage criterion to a program
mutation CCO Apply condition coverage criterion to a program
CDC Apply decision/condition coverage criterion to a program