Design, Implementation and Use of a Test Model Library for GUI Testing of Smartphone Applications

Model-based testing is a testing methodology in which the creation of tests can be performed automatically instead of manually. This is achieved by creating a test model, which is a formal description of the aspects of system to be tested. In practice, a test model for a realistic system is often too large and complicated to create all at once. It is therefore usually a better idea to create a number of smaller and simpler model components which can be combined into the test model. The flexibility of model-based testing can be improved by assembling the components into a model library. From the library a tester can choose a number of model components to be composed into a test model. This way, tests can be generated from a model which best corresponds to current testing needs. This thesis focuses on the design, implementation and use of a model library for GUI (graphical user interface) testing of smartphone applications. Modern smartphones can run complex applications which interact with each other; moreover, different phones communicate with each other, adding a further level of concurrency. As such, smartphone applications present a challenging domain for testing. We present the special considerations to be taken into account when creating model components intended to become a part of a model library, and our technical and methodological solutions to them. Flexibility is especially important: the model components have to be usable in different combinations according to the testing needs. This way features irrelevant to the tests to be generated can be left out of the model. Conversely, it is possible to create complex test models to test a variety of applications concurrently, or to test several devices and the communication between them. Furthermore, properly designed model components can be used in many different products, which can greatly reduce the effort needed for the creation of the models. Our experiences and case studies show that a well-designed model library can fulfill these needs.