Complete model-based equivalence class testing

In this article, we present a model-based black-box equivalence partition testing strategy, together with a formal proof of its completeness properties. The results apply to reactive systems with large, possibly infinite input data types and finite internal and output data ranges that may be enumerated with acceptable effort. The investigation is performed on a semantic level and applies to all concrete test models whose behavioural semantics can be encoded as a variant of state transition systems. Test suite construction is performed in relation to a given fault model \(\mathcal{F}\) for which a finite black-box test suite can be constructed which is complete with respect to \(\mathcal{F}\). It is shown how the test suite generation can be effectively implemented by model-based testing tools, using propositional representations of behavioural model semantics and constraint solvers. A SysML model of the ceiling speed monitoring function of the European Train Control System is presented as a case study, to explain theory application to a concrete modelling formalism.     

Event-driven web application testing based on model-based mutation testing

ContextEvent-Driven Software (EDS) is a class of software whose behavior is driven by incoming events. Web and desktop applications that respond to user-initiated events on their Graphical User Interface (GUI), or embedded software responding to events and signals received from the equipment in its operating environment are examples of EDS. Testing EDS poses great challenges to software testers. One of these challenges is the need to generate a huge number of possible event sequences that could sufficiently cover the EDS’s state space.ObjectiveIn this paper, we introduce a new six-stage testing procedure for event-driven web applications to overcome EDS testing challenges.MethodThe stages of the testing procedure include dividing the application based on its structure, creating functional graphs for each section, creating mutants from functional graphs, choosing coverage criteria to produce test paths, merging event sequences to make longer ones, and deriving and running test cases. We have analyzed our proposed testing procedure with the help of four metrics consisting of Fault Detection Density (FDD), Fault Detection Effectiveness (FDE), Mutation Score, and Unique Fault.ResultsUsing this procedure, we have prepared prioritized test cases and also discovered a list of unique faults by running the suggested test cases on a sample real-world web application called Academic E-mail System.ConclusionWe propose that our suggested testing procedure has some advantages such as creating functional graphs with requirements document, resolving the problem of removing infeasible test cases with these graphs and conditions on the “add edge” operator before creating mutants. But the suggested testing procedure, like any other method, had some drawbacks. Because most of the stages in the approach were performed manually, the testing time was increased.     

Component architecture of model-based testing environment

In the paper, an approach to constructing architecture of tools for model-based testing that rely on modern component-based technologies is presented. One of the basic ideas underlying this approach consists in application of noninvasive composition techniques, which make it possible to integrate a set of independently developed components into a complex system and reconfigure it without modifying codes of the components. The approach suggested in the paper is one of the first applications of the component-based technologies to designing test systems. A prototype implementation of the suggested approach based on available libraries is described, and an example of its use for test construction is presented.     

Delta-oriented model-based integration testing of large-scale systems

Software architecture specifications are of growing importance for coping with the complexity of large-scale systems. They provide an abstract view on the high-level structural system entities together with their explicit dependencies and build the basis for ensuring behavioral conformance of component implementations and interactions, e.g., using model-based integration testing. The increasing inherent diversity of such large-scale variant-rich systems further complicates quality assurance. In this article, we present a combination of architecture-driven model-based testing principles and regression-inspired testing strategies for efficient, yet comprehensive variability-aware conformance testing of variant-rich systems. We propose an integrated delta-oriented architectural test modeling and testing approach for component as well as integration testing that allows the generation and reuse of test artifacts among different system variants. Furthermore, an automated derivation of retesting obligations based on accurate delta-oriented architectural change impact analysis is provided. Based on a formal conceptual framework that guarantees stable test coverage for every system variant, we present a sample implementation of our approach and an evaluation of the validity and efficiency by means of a case study from the automotive domain.     

Voltage driven hard disk drive with voice coil model-based control

In this paper, we describe a new solution for driving the voice coil motor (VCM) in hard disk drives (HDDs), in which the usual current driver for the voice coil motor has been replaced by a voltage driver. When used in conjunction with PWM power stages, this solution becomes fully digital and has proven advantages in terms of cost, power dissipation and silicon area. To achieve the same performance of the current driver, the voltage driver requires a pre-filter placed at its input, to cancel out the electrical pole of the VCM. In the paper, we describe the voice coil model-based control (VCMC), a solution for implementing the pre-filter, which replicates the behavior of a current loop by using a model of the voice coil motor and its driver, including the saturation of the power stage. It is worth noticing that VCM resistance may change by 30% during HDD operations, increasing when the disk is performing repetitive seeks or decreasing when the disk cools down during track following. Such variation may lead to an unsatisfactory performance of the VCMC, so an adaptation mechanism, capable of tracking variations of VCM coil resistance, must be set up. This paper presents a pair of on-line estimation procedure, used to get the value of the VCM coil resistance during seek and track following, respectively. The first one is based on a standard LMS approach, aimed at identifying a simplified model of the plant with the least computational effort. The second exploits the presence of repetitive disturbances (RROs) to detect variations of plant gain and, in turn, of VCM resistance. It will be shown that both procedures are quite accurate in estimating variations of VCM resistance and their output can be used to perform on-line tuning of the VCMC. Experimental results show that the servo performance with the adaptive VCMC is not affected by resistance variation and equivalent to that of the standard current driver.     

一种关键字驱动的自动化测试框架

为了提高软件自动化测试脚本的可复用性,提出了一种基于关键字驱动的自动化测试框架（LKDT）。首先对目前现有自动化测试框架进行了归纳分析;然后提出了LKDT的系统架构,给出了其中所包含的关键技术;最后以实际的Linux桌面应用程序为例对LKDT框架与现有框架进行实际对比验证,结果表明该框架具有降低测试脚本规模、提高整体测试效率等优越性。     

Editorial to the theme section on model-based testing

Software and Systems Modeling - This theme on model-based testing (MBT) was organized in the context of advances in model-based testing (A-MOST) workshop series. Now in its fourteenth edition, this...     

A novel model-based testing approach for software product lines

Model-based testing relies on a model of the system under test. FineFit is a framework for model-based testing of Java programs. In the FineFit approach, the model is expressed by a set of tables based on Parnas tables. A software product line is a family of programs (the products) with well-defined commonalities and variabilities that are developed by (re)using common artifacts. In this paper, we address the issue of using the FineFit approach to support the development of correct software product lines. We specify a software product line as a specification product line where each product is a FineFit specification of the corresponding software product. The main challenge is to concisely specify the software product line while retaining the readability of the specification of a single system. To address this, we used delta-oriented programming, a recently proposed flexible approach for implementing software product lines, and developed: (1) delta tables as a means to apply the delta-oriented programming idea to the specification of software product lines; and (2) DeltaFineFit as a novel model-based testing approach for software product lines.     

一种基于模型的并发系统测试目的描述

提出了带约束事件的时序逻辑TLCE,用于描述系统运行中输入/输出事件之间的时序关系以及对事件参数的数据相关性约束。阐述了一种基于模型的并发系统测试框架,采用TLCE描述测试目的以引导测试用例生成。缓存一致性协议和会议协议的实例研究中所生成的测试用例集显著优于随机测试用例集。这说明了TLCE作为测试目的描述的有效性。     

基于模型的软件接口故障注入测试平台技术

针对软件接口类型多、接口故障注入自动控制复杂的困难以及目前缺少有效的软件接口故障注入工具现状,对软件故障注入中的交联接口故障注入技术展开研究,提出了一种基于模型的软件接口故障注入测试平台技术。通过交联接口测试可视化建模和接口故障注入算子设计,自动生成XML 格式的测试用例,并且通过基于XSLT的脚本自动化生成与执行技术实现测试的控制与执行。故障注入测试主机与接口故障注入器网络连接,接口故障注入器将接口故障数据转换成以太网、串口或CAN网络数据注入到被测软件中,并返回被测件输出数据到测试主机实现测试数据收集与判断。基于模型的软件接口故障注入测试平台具有较强的通用性与易用性,提高了接口故障注入测试的效率,降低了接口测试的成本。     

Wodel-Test: a model-based framework for language-independent mutation testing

Software and Systems Modeling - Mutation testing (MT) targets the assessment of test cases by measuring their efficiency to detect faults. This technique involves modifying the program under test...     

Temporal property patterns for model-based testing from UML/OCL

Software and Systems Modeling - This article describes a new property- and model-based testing approach using UML/OCL models, driven by temporal property patterns and a tool for assisting the...     

基于QTP的数据驱动测试开发

提出采用面向自动化测试的测试用例设计格式,通过QTP的编程功能,使用外部数据源来实现较复杂的数据驱动测试。具体方法是采用Excel作为测试数据源,制定Excel中测试数据的设计格式,建立专用的函数库来操作Excel数据,实现以数据为驱动的自动化测试。这一方法能有效地实现测试数据与测试脚本的分离,同时,测试数据的设计操作变得方便,数据的可读性增强,提高了测试效率和测试数据的维护效率。     

Exhaustive property oriented model-based testing with symbolic finite state machines

We advocate a fusion of property-oriented testing (POT) and model-based testing (MBT). The existence of a symbolic finite state machine (SFSM) model fulfilling the properties of interest is exploited for property-directed test data generation and to create a test oracle. A new test generation strategy is presented for verifying that the system under test (SUT) satisfies the same LTL safety conditions over a given set of atomic propositions as the model. We prove that this strategy is exhaustive in the sense that any SUT violating at least one of these formulae will fail at least one test case of the generated suite. It is shown that the existence of a model allows for significantly smaller exhaustive test suites as would be necessary for POT without reference models. As a corollary, the main theorem also generalises a known result about SFSM-based conformance testing for language equivalence. Our approach fits well to industrial development processes for (potentially safety-critical) cyber-physical systems, where both models and properties representing system requirements are elaborated for development, verification, and validation.     

Test case prioritization techniques for model-based testing: a replicated study

Recently, several test case prioritization (TCP) techniques have been proposed to order test cases for achieving a goal during test execution, particularly, revealing faults sooner. In the model-based testing (MBT) context, such techniques are usually based on heuristics related to structural elements of the model and derived test cases. In this sense, techniques’ performance may vary due to a number of factors. While empirical studies comparing the performance of TCP techniques have already been presented in literature, there is still little knowledge, particularly in the MBT context, about which factors may influence the outcomes suggested by a TCP technique. In a previous family of empirical studies focusing on labeled transition systems, we identified that the model layout, i.e., amount of branches, joins, and loops in the model, alone may have little influence on the effectiveness of TCP techniques investigated, whereas characteristics of test cases that actually fail definitely influences this aspect. However, we considered only synthetic artifacts in the study, which reduced the ability of representing properly the reality. In this paper, we present a replication of one of these studies, now with a larger and more representative selection of techniques and considering test suites from industrial systems as experimental objects. Our objective is to find out whether the results remain while increasing the validity in comparison to the original study. Results reinforce that there is no best performer among the investigated techniques and characteristics of test cases that fail represent an important factor, although adaptive random-based techniques are less affected by it.     

Experiences using Tedeso: an extensible and interoperable model-based testing platform

The integration of novel software quality assurance tools into existing development environments must be performed in ways that leverage the benefits of the tools while minimizing their impact on existing software processes. This supports the adoption of new methodologies with minimal interference into core business practices. This paper discusses the design of Tedeso, an extensible and interoperable model-based testing platform developed to facilitate the automatic generation of tests, while supporting the needs of different stakeholders in a diverse and broad organization. We discuss Tedeso key design characteristics, in particular its extensibility and interoperability, provided through the use of a workflow-driven service-oriented architecture, and show how it has enabled and facilitated the adoption of model-based testing techniques in different business units in different sectors within SIEMENS. We also discuss some issues that come from the adoption of service-oriented architectures, showing how they have been managed in our platform.     

3-DOF planar parallel-wire driven robot with an active balancer and its model-based adaptive control

This paper has proposed a parallel-wire driven robot (PWDR) with an active balancer, which is notably useful for such applications as ceiling maintenance and object conveyance near a ceiling in a factory. Because this robot is an under-actuated system, the uncertainty of the inertial parameters of the load strongly affects the resultant motion and reduces the control accuracy because of the dynamics interference. However, to date, the dynamics of this robot has not been thoroughly elucidated. Thus, this study analyzes the dynamics of a PWDR that controls three degree-of-freedom using two wires and an active balancer. Moreover, based on the dynamic analysis, a model-based adaptive controller for the parameter uncertainty of a load is proposed, and its effectiveness is demonstrated through simulation.     

Introducing plant features to model-based testing of programmable controllers in automation systems

This paper proposes a model-based test generation approach for programmable controllers that aims at reducing the length of a test sequence by applying plant features. The proposed approach does not require detailed or full knowledge of the plant behavior of a system under test, but it can achieve a remarkable reduction with simple plant features. As a result, the obtained test sequence can be significantly shorter than ones generated by complete testing methods; and meanwhile, it still reaches full coverage of the nominal behavior of the system under test. This makes it feasible to test large-scale systems, or to serve as an early test in the validation of safety critical systems. The proposed approach has been illustrated on a large-scale case study.     

Combining usage-based and model-based testing for service-oriented architectures in the industrial practice

International Journal on Software Tools for Technology Transfer - Usage-based testing focuses quality assurance on highly used parts of the software. The basis for this are usage profiles based on...