Abstract A Software Product Line (SPL) is a software development paradigm in which a family of software products shares a set of core assets. Testing has a vital role in both single-system development and SPL development in identifying potential faults by examining the behavior of a product or products, but it is especially challenging in SPL. There have been many research contributions in the SPL testing field; therefore, assessing the current state of research and practice is necessary to understand the progress in testing practices and to identify the gap between required techniques and existing approaches. This paper aims to survey existing research on SPL testing to provide researchers and practitioners with up-to-date evidence and issues that enable further development of the field. To this end, we conducted a Systematic Literature Review (SLR) with seven research questions in which we identified and analyzed 118 studies dating from 2003 to 2022. The results indicate that the literature proposes many techniques for specific aspects (e.g., controlling cost/effort in SPL testing); however, other elements (e.g., regression testing and non-functional testing) still need to be covered by existing research. Furthermore, most approaches are evaluated by only one empirical method, most of which are academic evaluations. This may jeopardize the adoption of approaches in industry. The results of this study can help identify gaps in SPL testing since specific points of SPL Engineering still need to be addressed entirely.

A Software Process Line (SPrL) is potentially suitable for constructing software development methodologies by reusing core assets. However, adopting this approach without prior assessment of its suitability can lead to failure. The aim of this paper is to identify a set of requirements that can be used for deciding whether to adopt the SPrL approach in an organization. Identification of the requirements was accomplished in two stages: the characteristics important in method tailoring were first identified via a Systematic Mapping Study (SMS) that focused on analyzing 43 primary studies; the degree of importance of the identified characteristics was then determined using a questionnaire survey in which 31 experts participated. By analyzing the results of the SMS and the survey, we have identified 12 product-related, 22 project-related, and 10 organization-related requirements. In addition to these requirements, we have also identified two relevant requirements by studying previous research on Software Product Lines (SPL) and Business Process Lines (BPL). The requirements thus identified can help organizations decide on whether to adopt the SPrL approach: the more an organization satisfies the requirements, the more frequently method tailoring occurs in that organization, and hence, the more justified it is to adopt the SPrL approach.