Test Suite Reduction Technique Research

In process of software development, the efficiency of regression testing is the most important factor which determines the success of the whole project, high regression test efficiency leads to the in-time delivery of the software with high qualities. Testers usually try to improve the regression test efficiency by only re-test a test-case subset of the whole regression test cases because they think there will be such a test-case subset which has the same effect with the old pre-selected test cases. For each iterating of the development, it’s quite expensive to re-test the whole system just because of the minor change of the source code, how to select the necessary test cases affected by the minor change of source code is a hot and difficult topic in the software regression test field.Existing techniques for the test suite reduction problems can be divided into non-demand-driven and demand-driven approach. The ideas of test suite reduction based on function slice are proposed in this paper trying to get the just necessary test cases for regression test after the source code has changed by the following two steps:First, concepts of function slice and function influence domain are proposed in this paper in order to get a rough test-case subset of the pre-selected test cases, proposed the concept of function influence domain. By comparing the old version of the source codes with the changed one, we can get the function relationship of the whole embedded system and the functions altered. We mark the changed functions as criteria functions in this paper. From the criteria functions, travel the function dependence graph to get the criteria slice graph and the node dependence graph, with which we can use to eliminate the unnecessary test cases from the ultimate test-case subset.Then, new algorithm named based combination relationship is suggested in this paper to reduce the rough test-case subset get in the first step because there are still some repeated and over-lapped test cases within the criteria function affection domain, trying to get the most reduced software regression final test cases.Finally, this paper use the idea of function slice to carry on regression test suite reduction experiment on embedded software system-ATM simulator. The result shows high efficiency when test with the final set of regression test suite get by the first two steps, it improves the efficiency of regression test of software regression test and reduces testing time and cost.