How are test smells treated in the wild? A tale of two empirical studies

Abstract

Developing test code may be a time­-consuming process that requires much effort and cost, especially when done manually. In addition, during this process, developers and testers are likely to adopt bad design choices, which may lead to introducing the so­-called test smells in the test code. As the test code with test smells size increases, these tests might become more complex, and as a consequence, much more challenging to understand and evolve them correctly. Therefore, test smells may harm the test code quality and maintenance and break the whole software testing activities. In this context, this study aims to understand whether software testing practitioners unintentionally insert test smells when they implement test code. We first carried out an expert survey to analyze the usage frequency of a set of test smells and then interviews to reach a deeper understanding of how practitioners deal with test smells. Sixty professionals participated in the survey, and fifty professionals participated in the interviews. The yielded results indicate that experienced professionals introduce test smells during their daily programming tasks, even when using their companies’ standardized practices. Additionally, tools support test development and quality improvement, but most interviewees are not aware of test smells’ concepts.