Based Multi-level Functional Model Of Software Regression Testing

Regression testing is one of the primary software testing techniques. It is applied to modified software to provide confidence that the changed parts behave as intended and the unchanged parts have not been adversely affected by the modification. Though regression testing is costly, it is absolutely necessary in test process. It is always a research focus that how to reduce the cost of regression test by reduce the test suite.Up to now, there are many software regression testing techniques, such as retest all regression technique, random select regression technique, minimization regression technique, data flow regression technique, safe regression technique etc. . However, all these techniques are code-based. Among these techniques, the safe regression guarantees the test quality but loses the efficiency at the same time. In addition, these techniques use the program data flow graph or the operation flow graph of a single operation and ignore the relationships between the operations which are also important for testing when performing the regression test analyses. Today, the third party of software testing is taking part in testing process. As the functional testing is very important for the third part of software testing, and the test for relationship between operations has attached importance, it is practical to investigate the regression technique based on function and operation specifications.In this thesis, we concentrate on the research of the efficient regression technique based on function. Considering the relationship between the operations,The multilayer functional model was put forward which is created from the operation specifications. At the same time, the method of creating the test cases of the multilayer functional model is also mentioned. The characteristics and disadvantages of some regression testing techniques are discussed, on which we bring out the safe selective regression technique. Firstly, the multilayer functional model was established which was based on the operation flows and then the test cases were created and performed. Secondly, the safe regression technique was used to analyze the testing. Finally, the modification-based regression technique or the cost-based regression technique was taken according to the time and the finance of the project. The safe selective regression technique not only guarantees the quality of the project but also reduces the cost and the regression test suite.The safe selective regression technique based on multilayer functional model was carried out in the project of the China Union Pay System integration te-sting-the switch subsystem functional testing. It is indicated that the technique is flexible, effective and practicable.