Lydie du Bousquet

An Approach to Symbolic Test Generation

Test generation is a program-synthesis problem: starting from the formal specification of a system under test, and from a test purpose describing a set of behaviours to be tested, compute a reactive program that observes an implementation of the system to detect nonconformant behaviour, while trying to control it towards satisfying the test purpose. In this paper we describe an approach for generating symbolic test cases, in the form of input-output automata with variables and parameters.

Filtering TOBIAS Combinatorial Test Suites

TOBIAS is a combinatorial testing tool, aimed at the production of large test suites. In this paper, TOBIAS is applied to conformance tests for model-based specifications (expressed with assertions, pre and post-conditions) and associated implementations. The tool takes advantage of the executable character of VDM or JML assertions which provide an oracle for the testing process. Executing large test suites may require a lot of time. This paper shows how assertions can be exploited at generation time to filter the set of test cases, and at execution time to detect inconclusive test cases.

Feature Interaction Detection Using Testing and Model-Checking Experience Report

We present an experiment in feature interaction detection. We studied the 12 features defined for the first feature interaction contest held in association with the 5th international Feature Interaction Workshop. We used a synchronous approach for modeling features, and both, a model-checker and a test generator for revealing interactions. The first part of the paper describes the feature modeling. The second part deals with the feature interaction detection carried out with a testing tool, and the last part addresses the use of a model-checker for the detection.

Automatic Test Generation for Java-Card Applets

Open-cards have introduced a new life cycle for smart card embedded applications. In the case of Java Card, they have raised the problem of embedded object-oriented applet validation. In this article, we describe a methodology for Java Card applet verification, and its application on a case study. This methodology is based on automatic test generation. We first take benefits of the Java Card platform validation, focusing on application conformity testing. Then, using UML, we model the applet and its probable communication with other embedded elements. In the next step, the resulting model is used to automatically generate test suites, using UMLAUT and TGV tools. The full process is iterative and incremental, in order to conform to an object-oriented approach. Moreover, this incremental process allows integrating priorities on validation, by focusing first on main functions and properties.

Mastering combinatorial explosion with the tobias-2 test generator

This paper briefly describes the second version of the Tobias combinatorial test generator. This version improves the architecture of the tool to include filtering and test selection mechanisms. These mechanisms, associated with an efficient implementation, allow to generate and filter test suites of up to 1 million test cases.

Reusing a JML Specification Dedicated to Verification for Testing, and Vice-Versa: Case Studies

Testing and verification are two activities which have the same objective: to ensure software dependability. In the Java context, the Java Modelling Language (JML) has been proposed as specification language. It can be used both for verification and test. Usually, the JML specification is designed with a specific purpose: test or verification. This article addresses the question of reusability of a JML specification provided for one activity (resp. verification or test) in the other context (resp. test or verification). Two different case studies are considered.

Towards Mutation Analysis for Lustre Programs

Mutation analysis is usually used to provide indication of the fault detection ability of a test set. It is mainly used for unit testing evaluation. This paper describes mutation analysis principles and their adaptation to the Lustre programming language. Alien-V, a mutation tool for Lustre is presented. Lesar model-checker is used for eliminating equivalent mutant. A first experimentation to evaluate Lutess testing tool is summarized.

Assertion-based test oracles for home automation systems

The Home Automation System (HAS) is a service-oriented application that facilitates the automation of a private home to improve the comfort and security of its residents. HAS is implemented using a service-oriented architecture. Many of the services in the HAS dynamically change their configuration during run-time. This occurs due to change in availability and bindings between services. Dynamic reconfigurations of services in the HAS presents several testing challenges, one being the specification of test oracles. In this paper, we give an approach for specifying test oracles for services in the HAS. We formally specify test oracles in the JML specification language. To verify service behavior in the presence of dynamic reconfigurations, we use mechanisms in the service architecture that notify dynamic changes along with run-time evaluation of JML specifications. We illustrate our approach using an example service in the H-Omega HAS developed on the OSGi#8482; and iPOJO service platform. To evaluate our approach, we developed a testing framework that allows for generation of tests with dynamic service reconfigurations. In addition, we seeded faults into the example service, and evaluated the effectiveness of the test oracles in revealing the faults using the generated tests.

Analysis of Testability Metrics for Lustre/Scade Programs

Testing is a validation process carried out to find errors in a system. Testability metrics aims at identifying parts of a design/code that are difficult to test. In this article, we focus on two testability metrics defined for systems written in Lustre/Scade. An intuitive interpretation was proposed for these metrics. The aims of the work described here is to check whether this intuitive interpretation can be consolidated with factual evidences.

Model-Based filtering of combinatorial test suites

Tobias is a combinatorial test generation tool which can efficiently generate a large number of test cases by unfolding a test pattern and computing all combinations of parameters. In this paper, we first propose a model-based testing approach where Tobias test cases are first run on an executable UML/OCL specification. This animation of test cases on a model allows to filter out invalid test sequences produced by blind enumeration, typically the ones which violate the pre-conditions of operations, and to provide an oracle for the valid ones. We then introduce recent extensions of the Tobias tool which support an incremental unfolding and filtering process, and its associated toolset. This allows to address explosive test patterns featuring a large number of invalid test cases, and only a small number of valid ones. For instance, these new constructs could mandate test cases to satisfy a given predicate at some point or to follow a given behavior. The early detection of invalid test cases improves the calculation time of the whole generation and execution process, and helps fighting combinatorial explosion.