Testing is one of the most prevalent and successful verification and validation (V&V) techniques used in the field of software engineering. While a large number of testing frameworks exist for general-purpose programming languages, providing testing facilities for any given executable Domain Specific Language (xDSL) remains a costly and challenging task. In this context, a standard such as the Test Description Language (TDL) appears as a suitable foundation for the definition of a generic testing approach for xDSLs. Unfortunately, TDL does not provide the domain-specific concepts required to write test cases for a given xDSL and does not include any model execution facilities. Our contribution addresses these limitations and thereby provides a fully generic testing approach for xDSLs based on TDL. Required TDL domain-specific concepts are automatically inferred from the xDSL definition through a model transformation into TDL. Model execution facilities are provided through the definition of a refined operational semantics for TDL. The application of our approach on 5 different xDSLs shows its generality and that it can successfully be used for testing executable models.

Low-code is a growing development approach supported by many platforms. It fills the gap between business and IT by supporting the active involvement of non-technical domain experts, named Citizen Developer, in the application development lifecycle.Low-code introduces new concepts and characteristics. However, it is not investigated yet in academic research to point out the existing challenges and opportunities when testing low-code software. This shortage of resources motivates this research to provide an explicit definition to this area that we call it Low-Code Testing.In this paper, we initially conduct an analysis of the testing components of five commercial Low-Code Development Platforms (LCDP) to present low-code testing advancements from a business point of view. Based on the low-code principles as well as the result of our analysis, we propose a feature list for low-code testing along with possible values for them. This feature list can be used as a baseline for comparing low-code testing components and as a guideline for building new ones. Accordingly, we specify the status of the testing components of investigated LCDPs based on the proposed features. Finally, the challenges of low-code testing are introduced considering three concerns: the role of citizen developer in testing, the need for high-level test automation, and cloud testing. We provide references to the state-of-the-art to specify the difficulties and opportunities from an academic perspective. The results of this research can be used as a starting point for future research in low-code testing area. CCS CONCEPTS• Software and its engineering → Software testing and debugging.

Executable Domain-Specific Languages (xDSLs) allow the definition and the execution of behavioral models. Some behavioral models are reactive, meaning that during their execution, they accept external events and react by exposing events to the external environment. Since complex interaction may occur between the reactive model and the external environment, they should be tested as early as possible to ensure the correctness of their behavior. In this paper, we propose a set of generic testing facilities for reactive xDSLs using the standardized Test Description Language (TDL). Given a reactive xDSL, we generate a TDL library enabling the domain experts to write and run event-driven TDL test cases for conforming reactive models. To further support the domain expert, the approach integrates interactive debugging to help in localizing defects, and mutation analysis to measure the quality of test cases. We evaluate the level of genericity of the approach by successfully writing,