Interaction-Based Test-Suite Minimization

Dale Blue, Itai Segall, Rachel Tzoref-Brill, and Aviad Zlotnick

IBM, USA; IBM Research, Israel

Track: Technical Research
Session: Test-Case Selection
Combinatorial Test Design (CTD) is an effective test planning technique that reveals faults resulting from feature interactions in a system. The standard application of CTD requires manual modeling of the test space, including a precise definition of restrictions between the test space parameters, and produces a test suite that corresponds to new test cases to be implemented from scratch. In this work, we propose to use Interaction-based Test-Suite Minimization (ITSM) as a complementary approach to standard CTD. ITSM reduces a given test suite without impacting its coverage of feature interactions. ITSM requires much less modeling effort, and does not require a definition of restrictions. It is appealing where there has been a significant investment in an existing test suite, where creating new tests is expensive, and where restrictions are very complex. We discuss the tradeoffs between standard CTD and ITSM, and suggest an efficient algorithm for solving the latter. We also discuss the challenges and additional requirements that arise when applying ITSM to real-life test suites. We introduce solutions to these challenges and demonstrate them through two real-life case studies.