Regression test selection model: a comparison between ReTSE and pythia

As software systems change and evolve over time regression tests have to be run to validate these changes. Regression testing is an expensive but essential activity in software maintenance. The purpose of this paper is to compare a new regression test selection model called ReTSE with Pythia. The ReTSE model uses decomposition slicing in order to identify the relevant regression tests. Decomposition slicing provides a technique that is capable of identifying the unchanged parts of a system. Pythia is a regression test selection technique based on textual differencing. Both techniques are compare using a Power program taken from Vokolos and Frankl’s paper. The analysis of this comparison has shown promising results in reducing the number of tests to be run after changes are introduced

Time-Space Efficient Regression Testing for Configurable Systems

Configurable systems are those that can be adapted from a set of options. They are prevalent and testing them is important and challenging. Existing approaches for testing configurable systems are either unsound (i.e., they can miss fault-revealing configurations) or do not scale. This paper proposes EvoSPLat, a regression testing technique for configurable systems. EvoSPLat builds on our previously-developed technique, SPLat, which explores all dynamically reachable configurations from a test. EvoSPLat is tuned for two scenarios of use in regression testing: Regression Configuration Selection (RCS) and Regression Test Selection (RTS). EvoSPLat for RCS prunes configurations (not tests) that are not impacted by changes whereas EvoSPLat for RTS prunes tests (not configurations) which are not impacted by changes. Handling both scenarios in the context of evolution is important. Experimental results show that EvoSPLat is promising. We observed a substantial reduction in time (22%) and in the number of configurations (45%) for configurable Java programs. In a case study on a large real-world configurable system (GCC), EvoSPLat reduced 35% of the running time. Comparing EvoSPLat with sampling techniques, 2-wise was the most efficient technique, but it missed two bugs whereas EvoSPLat detected all bugs four times faster than 6-wise, on average.Comment: 14 page

Configurations everywhere: implications for testing and debugging in practice

us.abb.com Many industrial systems are highly-configurable, complicat-ing the testing and debugging process. While researchers have developed techniques to statically extract, quantify and manipulate the valid system configurations, we conjecture that many of these techniques will fail in practice. In this paper we analyze a highly-configurable industrial applica-tion and two open source applications in order to quantify the true challenges that configurability creates for software testing and debugging. We find that (1) all three appli-cations consist of multiple programming languages, hence static analyses need to cross programming language barriers to work, (2) there are many access points and methods to modify configurations, implying that practitioners need con-figuration traceability and should gather and merge meta-data from more than one source and (3) the configuration state of an application on failure cannot be reliably deter-mined by reading persistent data; a runtime memory dump or other heuristics must be used for accurate debugging. We conclude with a roadmap and lessons learned to help prac-titioners better handle configurability now, and that may lead to new configuration-aware testing and debugging tech-niques in the future

Regression testing framework for test cases generation and prioritization

A regression test is a significant part of software testing. It is used to find the maximum number of faults in software applications. Test Case Prioritization (TCP) is an approach to prioritize and schedule test cases. It is used to detect faults in the earlier stage of testing environment. Code coverage is one of the features of a Regression Test (RT) that detects more number of faults from a software application. However, code coverage and fault detection are reducing the performance of existing test case prioritization by consuming a lot of time for scanning an entire code. The process of generating test cases plays an important role in the prioritization of test cases. The existing automated generation and prioritization techniques produces insufficient test cases that cause less fault detection rate or consumes more computation time to detect more faults. Unified Modelling Language (UML) based test case generation techniques can extract test cases from UML diagrams by covering maximum part of a module of an application. Therefore, a UML based test case generation can support a test case prioritization technique to find a greater number of faults with shorter execution time. A multi-objective optimization technique able to handle multiple objectives that supports RT to generate more number of test cases as well as increase fault detection rate and produce a better result. The aim of this research is to develop a framework to detect maximum number of faults with less execution time for improving the RT. The performance of the RT can be improved by an efficient test case generation and prioritization method based on a multi-objective optimization technique by handling both test cases and rate of fault detection. This framework consists of two important models: Test Case Generation (TCG) and TCP. The TCG model requires an UML use case diagram to extract test cases. A meta heuristic approach is employed that uses tokens for generating test cases. And, TCP receives the extracted test cases with faults as input to produce the prioritized set of test cases. The proposed research has modified the existing Hill Climbing based TCP by altering its test case swapping feature and detect faults in a reasonable execution time. The proposed framework intends to improve the performance of regression testing by generating and prioritizing test cases in order to find a greater number of faults in an application. Two case studies are conducted in the research in order to gather Test Case (TC) and faults for multiple modules. The proposed framework yielded a 92.2% of Average Percentage Fault Detection with less amount of testing time comparing to the other artificial intelligence-based TCP. The findings were proved that the proposed framework produced a sufficient amount of TC and found the maximum number of faults in less amount of time

On Run-Time Configuration Engineering

De nos jours, les utilisateurs changent le comportement de leur logiciel et l’adaptent à différentes situations et contexts, sans avoir besoin d’aucune modifications du code source ou recompilation du logiciel. En effet, les utilisateurs utilisent le mécanisme de configuration qui offre un ensemble d’options modifiables par les utilisateurs. D’après plusieurs études, des mauvaises valeurs des options de configuration causent des erreurs difficiles à déboguer. Plusieurs compagnies importantes, comme Facebook, Google et Amazon ont rencontré des pannes et erreurs sérieuses à cause de la configuration et qui sont considérées parmi les plus pires pannes dans ces compagnies. En plus, plusieurs études ont trouvé que le mécanisme de configuration augmente la complexité des logiciels et les rend plus difficile à utiliser. Ces problèmes ont un sérieux impact sur plusieurs facteurs de qualité, comme la sécurité, l’exactitude, la disponibilité, la compréhensibilité, la maintenabilité, et la performance des logiciels. Plusieurs études ont été élaborées dans des aspects spécifiques dans l’ingénierie des configurations, dont la majorité se concentrent sur le débogage des défaillances de configuration et les tests de la configuration des logiciels, tandis que peu de recherches traitent les autres aspects de l’ingénierie des configurations de logiciel, comme la création et la maintenance des options de configuration. Par contre, nous pensons que la configuration des logiciels n’a pas seulement un impact sur l’exactitude d’un logiciel, mais peut avoir un impact sur d’autres métriques de qualité comme la compréhensibilité et la maintenabilité. Dans cette thèse, nous faisons d’abord un pas en arrière pour mieux comprendre les activités principales liées du processus de l’ingénierie des configurations, avant d’évaluer l’impact d’un catalogue de bonnes pratiques sur l’exactitude et la performance du processus de la configuration des logiciels. Pour ces raisons, nous avons conduit un ensemble d’études empiriques qualitatives et quantitatives sur des grands projets libres. On a conduit une étude qualitative en premier lieu, dans laquelle nous avons essayé de comprendre le processus de l’ingénierie de configuration, les enjeux et problèmes que les développeurs rencontrent durant ce processus, et qu’est ce que les développeurs et chercheurs proposent pour aider les développeurs à améliorer la qualité de l’ingénierie de la configuration logiciel. En réalisant 14 entrevues semi structurées, un sondage et une revue systématique de littérature, nous avons défini un processus de l’ingénierie de configuration invoquant 9 activités, un ensemble de 22 challenges rencontrés en pratique et 24 recommandations des experts.----------ABSTRACT: Modern software applications allow users to change the behavior of a software application and adapt it to different situations and contexts, without requiring any source code modifications or recompilations. To this end, applications leverage a wide range of mechanisms of software configuration that provide a set of options that can be changed by users. According to several studies, incorrect values of software configuration options cause severe errors that are hard-to-debug. Major companies such as Facebook, Google, and Amazon faced serious outages and failures due to configuration, which are considered as some of the worst outages in these companies. In addition, several studies found that the mechanism of software configuration increases the complexity of a software system and makes it hard to use. Such problems have a serious impact on different quality factors, such as security, correctness, availability, comprehensibility, maintainability, and performance of software systems. Several studies have been conducted on specific aspects of configuration engineering, with most of them focusing on debugging configuration failures and testing software configurations, while only few research efforts focused on other aspects of configuration engineering, such as the creation and maintenance of configuration options. However, we think that software configuration can not only have a negative impact on the correctness of a software system, but also on other quality metrics, such as its comprehensibility and maintainability. In this thesis, we first take a step back to better understand the main activities involved in the process of run-time configuration engineering, before evaluating the impact of a catalog of best practices on the correctness and performance of the configuration engineering process. For these purposes, we conducted several qualitative and quantitative empirical studies on large repositories and open source projects. We first conducted a qualitative study, in which we tried to understand the configuration engineering process, the challenges and problems developers face during this process, and what practitioners and researchers recommend to help developers to improve their software configuration engineering quality. By conducting 14 semi-structured interviews, a large survey, and a systematic literature review, we identified a process of configuration engineering involving 9 activities, a set of 22 challenges faced in practice, and a set of 24 recommendations by experts