Retest test selection for product-line regression testing of variants and versions of variants

Abstract Testing is a crucial activity of product-line engineering. Due to shared commonality, testing each variant individually results in redundant testing processes. By adopting regression testing strategies, variants are tested incrementally by focusing on the variability between variants to reduce the overall testing effort. However, product lines evolve during their life-cycle to adapt, e.g., to changing requirements. Hence, quality assurance has also to be ensured after product-line evolution by efficiently testing respective versions of variants. In this paper, we propose retest test selection for product-line regression testing of variants and versions of variants. Based on delta-oriented test modeling, we capture the commonality and variability of an evolving product line by means of differences between variants and versions of variants. We exploit those differences to apply change impact analyses, where we reason about changed dependencies to be retested when stepping from a variant or a version of a variant to its subsequent one by selecting test cases for reexecution. We prototypically implemented our approach and evaluated its effectiveness and efficiency by means of two evolving product lines showing positive results.