Automatic Test Generation for Space

The European Space Agency (ESA) uses an engine to perform tests in the Ground Segment infrastructure, specially the Operational Simulator. This engine uses many different tools to ensure the development of regression testing infrastructure and these tests perform black-box testing to the C++ simulator implementation. VST (VisionSpace Technologies) is one of the companies that provides these services to ESA and they need a tool to infer automatically tests from the existing C++ code, instead of writing manually scripts to perform tests. With this motivation in mind, this paper explores automatic testing approaches and tools in order to propose a system that satisfies VST needs

The Optimisation of Stochastic Grammars to Enable Cost-Effective Probabilistic Structural Testing

The effectiveness of probabilistic structural testing depends on the characteristics of the probability distribution from which test inputs are sampled at random. Metaheuristic search has been shown to be a practical method of optimis- ing the characteristics of such distributions. However, the applicability of the existing search-based algorithm is lim- ited by the requirement that the software’s inputs must be a fixed number of numeric values. In this paper we relax this limitation by means of a new representation for the probability distribution. The repre- sentation is based on stochastic context-free grammars but incorporates two novel extensions: conditional production weights and the aggregation of terminal symbols represent- ing numeric values. We demonstrate that an algorithm which combines the new representation with hill-climbing search is able to effi- ciently derive probability distributions suitable for testing software with structurally-complex input domains

Pairwise-Korat : automated testing using Korat in an industrial setting

textIn this report, we present an algorithm for testing applications which takes structurally complex test inputs. The algorithm, Pairwise-Korat, adopts Korat -- an algorithm for constraint-based generation of structurally complex test inputs. Korat takes (1) an imperative predicate which specifies the desired structural integrity constraints and (2) a finitization which bounds the desired test inputs size. Korat performs a systematic search to generate all test inputs (within the bounds) for which the predicate returns true. We present how to generate test inputs in Korat and how to execute test inputs in parallel. The inputs that Korat generates enable bounded-exhaustive testing that checks the code under test exhaustively for all inputs within the given bounds. We also describe a novel methodology for reducing the number of equivalent inputs that Korat generates. Our development of test input generation and the methodology for reducing equivalent inputs are motivated by testing applications developed at eBay. The experimental results show that the Pairwise-Korat achieves great performance in finding defects and increasing test coverage and the algorithm outperforms current manual solutions adopted at the company.Electrical and Computer Engineerin