利用MC/DC减少测试集大小的方法的研究

随着软件的发展，测试技术也在发展。MC／DC即修改条件／判定覆盖，是一种较新的结构覆盖准则，它是在C／DC（条件／判定覆盖）的基础上发展起来的。与其它结构覆盖准则相比，它只是线性地增加了测试用例的数量，使得软件测试更加具有可操作性。而对于测试来说，测试用例的选择和优化是至关重要的。在探讨MC／DC的基础上，利用MC／DC的特点，初步提出了利用MC／DC进行测试集减少的方法，使得减少后的测试集与原测试集对测试需求有着相同或相似的覆盖率，并对此方法的利弊做了一定的分析。     

MC/DC准则在嵌入式软件测试中的应用

MC/DC准则被广泛应用于高安全性的嵌入式软件独立验证和确认中,是一种实用而高效的软件结构覆盖率验证准则。基于嵌入式软件测试的特点与MC/DC的基本概念,提出了MC/DC的最小测试集的形成方法。结合工程应用实例,利用自动化测试工具实现MC/DC测试流程。MC/DC准则在核电仪控系统中的成功应用,对于航空、军工、机器人等高安全性和高可靠性领域有着很好的借鉴作用。     

更改的判定条件覆盖测试技术研究

与语句覆盖、判定覆盖、条件覆盖、判定条件覆盖、多重条件覆盖相比，路径覆盖具有更强的结构覆盖率。但其需要更庞大的测试用例，事实上它并不实用。近年来，一种相对新颖和优秀的结构覆盖准则一一更改的判定条件覆盖(MC/DC)应运而生，它继承了多重条件覆盖的优点，同时只是线性地增加了测试用例的数量。因此，在许多重要的软件，尤其是以嵌入式和实时性为特征的航空机载软件中得到广泛的应用．介绍了MC／DC的特点、设计方法、评估策略及工程应用。     

耦合条件的MC/DC测试用例集生成算法

MC/DC是一套航电A级软件的测试覆盖性准则,可以有效减少测试用例量.针对如何快速获取尽可能小的测试用例集这一难点展开研究,重点关注于具有耦合条件的逻辑表达式,提出了两套解决方案,分别用于解决零耦合/弱耦合条件和强耦合条件问题,并给出了示例证明.结果表明,灵活使用两套算法,可以全面解决一般逻辑表达式的MC/DC测试用例集的快速生成问题.     

LDRA Testbed中常用覆盖测试方法研究

使用LDRA Testbed对实例进行覆盖测试,介绍了获得语句覆盖率、分支覆盖率以及MC/DC覆盖率的方法,同时阐述了这3种覆盖测试方法的优劣,表明了LDRA Testbed能够有效获取被测软件的动态覆盖率信息,降低测试难度,提高测试效率。     

基于MC／DC生成测试用例方法研究

设计和编写测试用例是软件测试中最重要的步骤。分析机栽系统软件需求,系统状态转换或事件触发总是以满足一个或多个条件为前提的。因此在将需求抽象成布尔表达式基础上,依据MC／DC准则,研究了一个布尔运算符替换算法。将该算法实现为工具,用于生成满足MC／DC准则要求的测试用例。最后结合实例验证该工具的实用性。     

基于二叉树满足MC/DC测试用例设计方法

软件测试是保证软件质量的有效方法,但测试工作过程繁琐,工作量较多。探索高效、可靠的测试用例设计方法一直是大家追求的目标,随着航空航天产品逻辑复杂性的提高及软件规模的日益增大,这种要求也变得更加迫切。依据MC/DC设计的测试用例既提高了测试用例设计的效率又增加了测试覆盖率,比较适合测试逻辑关系相对复杂的软件。当前的很多软件测试工具提供了软件测试覆盖率的判定功能,可以评定设计出的测试用例是否满足MC/DC的要求,而软件测试人员需要的是逆向的过程,论文提出应用唯一原因法和屏蔽法原理设计测试用例,可达到根据逻辑关系自动生成满足MC/DC要求测试用例的目的,提高了测试用例设计的效率。     

面向故障定位的基于MC/DC的测试用例约简方法

对不断更新的软件进行回归测试时,持续增加的测试用例会造成累计测试用例数量庞大,进而影响测试成本。在故障定位领域,已有研究在考虑语句覆盖、路径覆盖等的基础上,提出了CMR&PVR等不同的测试用例约简方法。然而,这些方法在一定程度上影响了原始测试用例集的MC/DC(修订的条件/判定)覆盖率。提出一种以MC/DC覆盖为基础的综合测试用例约简方法MCDCR,利用该方法对原始测试用例集约简后,在确保原有故障定位准确性并保持较高约简比的同时,大幅提高了测试用例对程序的MC/DC覆盖率。采用Ochiai方法在Siemens 程序集上进行了实验及验证,结果表明MCDCR约简方法的综合效果明显优于已有的约简方法。     

基于图的MC/DC 最小测试用例集快速生成算法

依针对MC／DC最4,N试用例集生成效率的问题,依据MC／DC准则,以条件判定组合的复杂逻辑关系为研究对象,采用将原始布尔表达式转化为语法树,再将语法树转化为图,分析图中节点对判定结果的影响的方法,研究了基于图快速生成最小测试用例集的算法．最后结合实倒对该算法进行了验证,并与其他算法进行了比较,结果表明该算法在手动和自动生成最小测试用例集时具有实用性和优越性．     

对逻辑覆盖软件测试准则的公理化评估

由于形式规格说明采用一种精确、一致、容易被机器自动处理的符号系统来描述软件需求,因而形式规格说明为测试用例的自动生成和软件功能的验证提供了基础.在基于形式规格说明的测试过程中逻辑覆盖测试准则是一组常用的测试准则,如何选择和使用其中的每个测试准则是应用这组测试准则时面临的主要问题.因此分析和比较这组测试准则中每个测试准则的性质将为测试工程师选择测试准则提供指导和帮助.对测试充分性准则的公理化评估是一种比较测试准则的方式,这种方式将对理想的测试准则的直觉需求定义为一组公理,然后通过检查测试准则是否满足该组公理来分析和比较相应的测试准则.描述了一组理想的逻辑覆盖测试准则应该具有的性质和用来确定一个测试充分性准则是否完全的生成算法.这组性质被形式化地定义为一组公理.利用这种形式化的定义,用定理的形式精确地给出了这些性质之间的关系.最后通过这组公理系统来评估现有的逻辑覆盖测试准则.评估的结果为测试人员在实际过程中选择逻辑覆盖测试准则提供了指导.     

Making a concolic tester achieve increased MC/DC

Concolic testing techniques do not necessarily aim to achieve a specific MC/DC coverage. On the other hand, MC/DC is considered as a standard and a strong test coverage criterion. It is mandated for many categories of applications such as safety critical software. We present an automated code transformation technique that can be used as a front end to a concolic tester for achieving high MC/DC. Our experimentation on seventeen moderately complex programs shows that our approach achieves higher MC/DC over traditional concolic tester on the average by 24.84 %, for the code we tested.     

From MC/DC to RC/DC: formalization and analysis of control-flow testing criteria

This paper describes an approach to the formalization of existing criteria used in computer systems software testing and proposes a new Reinforced Condition/Decision Coverage (RC/DC) criterion. This new criterion has been developed from the well-known Modified Condition/Decision Coverage (MC/DC) criterion and is more suitable for the testing of safety-critical software where MC/DC may not provide adequate assurance. As a formal language for describing the criteria, the Z notation has been selected. Formal definitions in the Z notation for RC/DC, as well as MC/DC and other criteria, are presented. Specific examples of using these criteria for specification-based testing are considered and some features are formally proved. This characterization is helpful in the understanding of different types of testing and also the correct application of a desired testing regime. Received July 2004 Revised November 2005 Accepted November 2005 by J. Derrick, M. Harman and R.M. Herons     

Test-suite reduction and prioritization for modified condition/decision coverage

Software testing is particularly expensive for developers of high-assurance software, such as software that is produced for commercial airborne systems. One reason for this expense is the Federal Aviation Administration's requirement that test suites be modified condition/decision coverage (MC/DC) adequate. Despite its cost, there is evidence that MC/DC is an effective verification technique and can help to uncover safety faults. As the software is modified and new test cases are added to the test suite, the test suite grows and the cost of regression testing increases. To address the test-suite size problem, researchers have investigated the use of test-suite reduction algorithms, which identify a reduced test suite that provides the same coverage of the software according to some criterion as the original test suite, and test-suite prioritization algorithms, which identify an ordering of the test cases in the test suite according to some criteria or goals. Existing test-suite reduction and prioritization techniques, however, may not be effective in reducing or prioritizing MC/DC-adequate test suites because they do not consider the complexity of the criterion. This paper presents new algorithms for test-suite reduction and prioritization that can be tailored effectively for use with MC/DC. The paper also presents the results of empirical studies of these algorithms.     

无人机飞行控制系统软件白盒测试用例设计研究

软件测试在软件生存期中占有非常突出的重要地位，也是保证软件质量的重要手段，首先介绍软件测试中白盒测试的方法；然后以某型无人机飞行控制系统软件测试为例，具体研究了无人机飞行控制系统软件白盒测试的测试用例的设计方法，总结了白盒测试的测试用例的设计步骤，比较了几种覆盖准则，指出了修正条件／判定覆盖的优点，提出并讨论了无人机飞行控制系统软件白盒测试的覆盖准则。     

On the effect of test-suite reduction on automatically generated model-based tests

Model checking techniques can be successfully employed as a test-case generation technique to generate tests from formal models. The number of tests-cases produced, however, is typically large for complex coverage criteria such as MC/DC. Test-suite reduction can provide us with a smaller set of test-cases that preserve the original coverage—often a dramatically smaller set. Nevertheless, one potential drawback with test-suite reduction is that this might affect the quality of the test-suite in terms of fault finding. Previous empirical studies provide conflicting evidence on this issue. To further investigate the problem and determine its effect when testing implementations derived from formal models of software we performed an experiment using a large case example of a Flight Guidance System, generated reduced test-suites for a variety of structural coverage criteria while preserving coverage, and recorded their fault finding effectiveness. Our results indicate that the size of the specification based test-suites can be dramatically reduced and that the fault detection of the reduced test-suites is adversely affected. In this report we describe our experiment, analyze the results, and discuss the implications for testing based on formal specifications. This work has been partially supported by NASA grant NAG-1-224 and NASA contract NCC-01001. We also want to thank the McKnight Foundation for their generous support over the years.

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软件白盒测试的方法与实践

主要介绍了进行软件白盒测试,包括静态测试分析、覆盖测试分析、运行时错误检测的方法、工具及实践。