From Temporal Models to Property-Based Testing

This paper presents a framework to apply property-based testing (PBT) on top of temporal formal models. The aim of this work is to help software engineers to understand temporal models that are presented formally and to make use of the advantages of formal methods: the core time-based constructs of a formal method are schematically translated to the BeSpaceD extension of the Scala programming language. This allows us to have an executable Scala code that corresponds to the formal model, as well as to perform PBT of the models functionality. To model temporal properties of the systems, in the current work we focus on two formal languages, TLA+ and FocusST.Comment: Preprint. Accepted to the 12th International Conference on Evaluation of Novel Approaches to Software Engineering (ENASE 2017). Final version published by SCITEPRESS, http://www.scitepress.or

How well are your requirements tested?

We address the question: to what extent does covering requirements ensure that a test suite is effective at revealing faults? To answer it, we generate minimal test suites that cover all requirements, and assess the tests they contain. They turn out to be very poor-ultimately because the notion of covering a requirement is more subtle than it appears to be at first. We propose several improvements to requirements tracking during testing, which enable us to generate minimal test suites close to what a human developer would write. However, there remains a class of plausible bugs which such suites are very poor at finding, but which random testing finds rather easily

Test Maintenance for Machine Learning Systems: A Case Study in the Automotive Industry

Machine Learning (ML) systems have seen widespread use for automated decision making. Testing is essential to ensure the quality of these systems, especially safety-critical autonomous systems in the automotive domain. ML systems introduce new challenges with the potential to affect test maintenance, the process of updating test cases to match the evolving system. We conducted an exploratory case study in the automotive domain to identify factors that affect test maintenance for ML systems, as well as to make recommendations to improve the maintenance process. Based on interview and artifact analysis, we identified 14 factors affecting maintenance, including five especially relevant for ML systems—with the most important relating to non-determinism and large input spaces. We also proposed ten recommendations for improving test maintenance, including four targeting ML systems—in particular, emphasizing the use of test oracles tolerant to acceptable non-determinism. The study’s findings expand our knowledge of test maintenance for an emerging class of systems, benefiting the practitioners testing these systems

A Survey of Algorithmic Debugging

"© ACM, 2017. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in ACM Computing Surveys, {50, 4, 2017} https://dl.acm.org/doi/10.1145/3106740"[EN] Algorithmic debugging is a technique proposed in 1982 by E. Y. Shapiro in the context of logic programming. This survey shows how the initial ideas have been developed to become a widespread debugging schema ftting many diferent programming paradigms and with applications out of the program debugging feld. We describe the general framework and the main issues related to the implementations in diferent programming paradigms and discuss several proposed improvements and optimizations. We also review the main algorithmic debugger tools that have been implemented so far and compare their features. From this comparison, we elaborate a summary of desirable characteristics that should be considered when implementing future algorithmic debuggers.This work has been partially supported by the EU (FEDER) and the Spanish Ministerio de Economia y Competitividad under grant TIN2013-44742-C4-1-R, TIN2016-76843-C4-1-R, StrongSoft (TIN2012-39391-C04-04), and TRACES (TIN2015-67522-C3-3-R) by the Generalitat Valenciana under grant PROMETEO-II/2015/013 (SmartLogic) and by the Comunidad de Madrid project N-Greens Software-CM (S2013/ICE-2731).Caballero, R.; Riesco, A.; Silva, J. (2017). A Survey of Algorithmic Debugging. ACM Computing Surveys. 50(4):1-35. https://doi.org/10.1145/3106740S135504Abramson, D., Foster, I., Michalakes, J., & Sosič, R. (1996). Relative debugging. Communications of the ACM, 39(11), 69-77. doi:10.1145/240455.240475K. R. Apt H. A. Blair and A. Walker. 1988. Towards a theory of declarative knowledge. In Foundations of Deductive Databases and Logic Programming J. Minker (Ed.). Morgan Kaufmann Publishers Inc. San Francisco CA 89--148. 10.1016/B978-0-934613-40-8.50006-3 K. R. Apt H. A. Blair and A. Walker. 1988. Towards a theory of declarative knowledge. In Foundations of Deductive Databases and Logic Programming J. Minker (Ed.). Morgan Kaufmann Publishers Inc. San Francisco CA 89--148. 10.1016/B978-0-934613-40-8.50006-3Arora, T., Ramakrishnan, R., Roth, W. G., Seshadri, P., & Srivastava, D. (1993). Explaining program execution in deductive systems. Lecture Notes in Computer Science, 101-119. doi:10.1007/3-540-57530-8_7E. Av-Ron. 1984. Top-Down Diagnosis of Prolog Programs. Ph.D. Dissertation. Weizmann Institute. E. Av-Ron. 1984. Top-Down Diagnosis of Prolog Programs. Ph.D. Dissertation. Weizmann Institute.A. Beaulieu. 2005. Learning SQL. O’Reilly Farnham UK. A. Beaulieu. 2005. Learning SQL. O’Reilly Farnham UK.D. Binks. 1995. Declarative Debugging in Gödel. Ph.D. Dissertation. University of Bristol. D. Binks. 1995. Declarative Debugging in Gödel. Ph.D. Dissertation. University of Bristol.B. Braßel and H. Siegel. 2008. Debugging Lazy Functional Programs by Asking the Oracle. Springer-Verlag Berlin 183--200. DOI:http://dx.doi.org/10.1007/978-3-540-85373-2_11 10.1007/978-3-540-85373-2_11 B. Braßel and H. Siegel. 2008. Debugging Lazy Functional Programs by Asking the Oracle. Springer-Verlag Berlin 183--200. DOI:http://dx.doi.org/10.1007/978-3-540-85373-2_11 10.1007/978-3-540-85373-2_11Caballero, R. (2005). A declarative debugger of incorrect answers for constraint functional-logic programs. Proceedings of the 2005 ACM SIGPLAN workshop on Curry and functional logic programming - WCFLP ’05. doi:10.1145/1085099.1085102Caballero, R., García-Ruiz, Y., & Sáenz-Pérez, F. (2012). Declarative Debugging of Wrong and Missing Answers for SQL Views. Lecture Notes in Computer Science, 73-87. doi:10.1007/978-3-642-29822-6_9Caballero, R., García-Ruiz, Y., & Sáenz-Pérez, F. (2015). Debugging of wrong and missing answers for datalog programs with constraint handling rules. Proceedings of the 17th International Symposium on Principles and Practice of Declarative Programming - PPDP ’15. doi:10.1145/2790449.2790522Caballero, R., Martin-Martin, E., Riesco, A., & Tamarit, S. (2015). A zoom-declarative debugger for sequential Erlang programs. Science of Computer Programming, 110, 104-118. doi:10.1016/j.scico.2015.06.011Caballero, R., & Rodríguez-Artalejo, M. (2002). A Declarative Debugging System for Lazy Functional Logic Programs. Electronic Notes in Theoretical Computer Science, 64, 113-175. doi:10.1016/s1571-0661(04)80349-9Ceri, S., Gottlob, G., & Tanca, L. (1989). What you always wanted to know about Datalog (and never dared to ask). IEEE Transactions on Knowledge and Data Engineering, 1(1), 146-166. doi:10.1109/69.43410Chen, M., Mao, S., & Liu, Y. (2014). Big Data: A Survey. Mobile Networks and Applications, 19(2), 171-209. doi:10.1007/s11036-013-0489-0Chitil, O., & Davie, T. (2008). Comprehending finite maps for algorithmic debugging of higher-order functional programs. Proceedings of the 10th international ACM SIGPLAN symposium on Principles and practice of declarative programming - PPDP ’08. doi:10.1145/1389449.1389475Chitil, O., Faddegon, M., & Runciman, C. (2016). A Lightweight Hat. Proceedings of the 28th Symposium on the Implementation and Application of Functional Programming Languages - IFL 2016. doi:10.1145/3064899.3064904O. Chitil C. Runciman and M. Wallace. 2001. Freja Hat and Hood—A Comparative Evaluation of Three Systems for Tracing and Debugging Lazy Functional Programs. Springer Berlin 176--193. O. Chitil C. Runciman and M. Wallace. 2001. Freja Hat and Hood—A Comparative Evaluation of Three Systems for Tracing and Debugging Lazy Functional Programs. Springer Berlin 176--193.O. Chitil C. Runciman and Malcolm Wallace. 2003. Transforming Haskell for Tracing. Springer-Verlag Berlin 165--181. DOI:http://dx.doi.org/10.1007/3-540-44854-3_11 10.1007/3-540-44854-3_11 O. Chitil C. Runciman and Malcolm Wallace. 2003. Transforming Haskell for Tracing. Springer-Verlag Berlin 165--181. DOI:http://dx.doi.org/10.1007/3-540-44854-3_11 10.1007/3-540-44854-3_11Minh Ngoc Dinh, Abramson, D., & Chao Jin. (2014). Scalable Relative Debugging. IEEE Transactions on Parallel and Distributed Systems, 25(3), 740-749. doi:10.1109/tpds.2013.86Faddegon, M., & Chitil, O. (2015). Algorithmic debugging of real-world haskell programs: deriving dependencies from the cost centre stack. ACM SIGPLAN Notices, 50(6), 33-42. doi:10.1145/2813885.2737985Faddegon, M., & Chitil, O. (2016). Lightweight computation tree tracing for lazy functional languages. Proceedings of the 37th ACM SIGPLAN Conference on Programming Language Design and Implementation - PLDI 2016. doi:10.1145/2908080.2908104Ferrand, G. (1987). 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Algorithmic Debugging and Literate Programming to Generate Feedback in Intelligent Tutoring Systems. KI 2014: Advances in Artificial Intelligence, 37-48. doi:10.1007/978-3-319-11206-0_

Invariant detection meets Random test case generation

Dissertação de mestrado em Engenharia de InformáticaFull fledged verification of software ensures correction to a level that no other technique can reach. However it requires precise and unambiguous specifications of requirements, functionality and technical aspects of the software to be verified. Furthermore, it requires that these specifications together with the produced models and code be checked for conformity. This represents beyond doubt an investment that most developers and companies are neither able nor willing to make. Although testing can not reach the same level of assurance as full fledged verification, it is the most widely accepted and used technique to validate expectations about software products. Testing is the most natural way of checking that a piece of software is doing what the developers expect it to do. Improvements to test case generation have the potential to produce a great impact in the state of the art of software engineering, by putting Software Testing closer to Formal Software Verification. This is an exploratory project, aimed at surveying the current state of the art in the field of test case generation and related techniques for the Java language, eventually suggesting possible advancements in the field.A verdadeira verificação de software garante correcção de software a um nível que nenhuma outra técnica consegue igualar. No entanto, exige especificações precisas e inequívocas de requisitos de funcionalidade e aspectos técnicos do software a ser verificado. Além disso, é necessário que as especificações, juntamente com os modelos produzidos e código sejam verificados quanto à sua conformidade. Isto representa indubitavelmente um investimento que a maioria dos profissionais e empresas não são capazes, nem estão dispostos a fazer. Embora os testes não alcancem o mesmo nível de garantia como a verificação completa, é a técnica mais amplamente aceite e usada para validar as especificações sobre produtos de software. O teste é a forma mais natural de verificar que um pedaço de software cumpre o que os programadores esperam que faça. Melhorias na geração de boletins de teste têm o potencial de produzir um grande impacto no estado da arte da engenharia de software, colocando o teste de software mais perto da Verificação Formal de Software. Este projecto é de carácter exploratório, visando o levantamento do estado actual da área de geração de casos de teste para a linguagem Java e técnicas relacionadas, sugerindo avanços possíveis nesta área de validação de softwar

Tools for Discovery, Refinement and Generalization of Functional Properties by Enumerative Testing

This thesis presents techniques for discovery, refinement and generalization of properties about functional programs. These techniques work by reasoning from test results: their results are surprisingly accurate in practice, despite an inherent uncertainty in principle. These techniques are validated by corresponding implementations in Haskell and for Haskell programs: Speculate, FitSpec and Extrapolate. Speculate discovers properties given a collection of black-box function signatures. Properties discovered by Speculate include inequalities and conditional equations. These properties can contribute to program understanding, documentation and regression testing. FitSpec guides refinements of properties based on results of black-box mutation testing. These refinements include completion and minimization of property sets. Extrapolate generalizes counterexamples of test properties. Generalized counterexamples include repeated variables and side-conditions and can inform the programmer what characterizes failures. Several example applications demonstrate the effectiveness of Speculate, FitSpec and Extrapolate

Software testing with QuickCheck

This paper presents a tutorial, with extensive exercises, in the use of Quviq QuickCheck - a property-based testing tool for Erlang, which enables developers to formulate formal specifications of their code and to use them for testing. We cover the basic concepts of properties and test-data generators, properties for testing abstract data types, and a state-machine modelling approach to testing stateful systems. Finally we discuss applications of QuickCheck in industry