Context: A Dynamically Adaptive System (DAS) supports runtime adaptations to handle changes in the operational environment. These adaptations can change the system’s structure or behavior and even the logic of its adaptation mechanism. However, these adaptations may insert defects, leading the system to fail at runtime.

Objective: Aiming to identify these failures, testing can be executed to verify the system at runtime. Studies in the literature mostly focus on testing to verify the adaptations at design-time or functionalities at runtime, rather than exercising the adaptation mechanism at runtime. So, we propose RETAkE (RuntimE Testing of dynamically Adaptive systEms).

Method: RETAkE is an approach to perform the runtime testing based on the system’s context variability and feature modeling. RETAkE tests the adaptation mechanism, enabling the verification of its adaptation rules with the system’s variability model. The runtime testing is supported by the verification of behavioral properties. For the evaluation, we used the mutation testing technique with two DAS. We also conducted an evaluation to measure the overhead introduced when RETAkE is integrated to the DAS.

Results: RETAkE identified the mutants in the two mobile DAS, but the results vary due to the probabilistic nature of the approach to generate test sequences. Regarding the overhead, test sequences of size 30 had a low impact. However, bigger test sequences increase the overhead.

Conclusion: The integration of RETAkE to the DAS adaptation mechanism can support the discovery of adaptation failures that occur at runtime. Furthermore, the results of the evaluation suggest its feasibility to perform runtime testing.

上下文：动态自适应系统（DAS）支持运行时自适应，以处理操作环境中的更改。这些适应可以改变系统的结构或行为，甚至改变其适应机制的逻辑。但是，这些修改可能会插入缺陷，从而导致系统在运行时发生故障。

目标：为了识别这些故障，可以在运行时执行测试以验证系统。文献中的研究主要集中在测试以验证设计时的适应性或运行时的功能，而不是在运行时行使适应机制。因此，我们提出了RETAkE（动态自适应系统的RuntimE测试）。

方法： RETAkE是一种基于系统的上下文可变性和特征建模执行运行时测试的方法。RETAkE测试适应机制，从而可以使用系统的可变性模型验证其适应规则。行为属性的验证支持运行时测试。为了进行评估，我们使用了带有两个DAS的突变测试技术。我们还进行了评估，以衡量将RETAkE集成到DAS中时引入的开销。

结果： RETAkE在两个移动DAS中鉴定了突变体，但由于生成测试序列的方法的概率性质，结果有所不同。关于开销，大小为30的测试序列影响很小。但是，较大的测试序列会增加开销。

结论： RETAkE与DAS自适应机制的集成可以支持发现运行时发生的自适应失败。此外，评估结果表明了执行运行时测试的可行性。