Test Selection with Equivalence Class Partitioning

Software maintenance activities account for as much as two-thirds of the overall costs on an average. A way to select a subset from a test suite is thus extremely essential to save cost and provide confidence that the program modifications are correct. Though substantial research results on test selection techniques have been reported in the literature, very few software industries deploy systematic test selection strategies or automation support. The expert judgment is the most often used in the industry for identification of relevant cases for re-testing that is usually difficult and inefficient. This paper introduces an agile strategy that divides a test suite with Equivalence Classification Partition (ECP) into sub-domains. The subset selected from the sub-domains provides a complete and comprehensive coverage of test criteria. The ECP is expressed with Classification Tree Method (CTM) and easy to be adjusted for different goals flexibly, e.g., re-test for modified function, delivery deadline or human resource limit. Our method is implemented as a tool and evaluated on two projects experimentally. The results demonstrated that this method can improve the efficiency and effectiveness of re-testing greatly.