Bottom-up reuse for multi-level testing

Lifecycle models divide the test process into consecutive test levels that are considered independently. This strict separation obstructs the view on the test process as a whole and fails to reflect the commonalities across test levels. Multi-level testing is an emerging approach that addresses the challenge of integrating test levels, putting particular emphasis on embedded systems. In this paper, we introduce a test level integration strategy based on reuse that is called bottom-up reuse. In addition, we present a test level instrument that seamlessly supports this strategy: multi-level test cases. We also provide a case study that reflects the positive results we have obtained in practice so far and demonstrates the feasibility of our test level integration approach. Bottom-up reuse and multi-level test cases lead to testing earlier on in the development process while reducing the effort required by test specification, test design, and test implementation.