An Industrial Case Study on Test Cases as Requirements

Benefits and challenges of using test cases as requirements.

This paper has an interesting history. Based on the interviews from our big alignment case study, we analyzed a subset from the perspective of using test cases as requirements. The paper was first rejected for methodological reasons at a conference, then slightly revised and accepted at the XP conference – and nominated for the best paper award! We also accepted the invitation to extend the paper for a special section in a journal. I blog about the extension in its corresponding post.

Elizabeth Bjarnason, Michael Unterkalmsteiner, Emelie Engström, and Markus Borg. An Industrial Case Study on Test Cases as Requirements, In Proc. of the 6th International Conference on Agile Software Development (XP), Helsinki, Finland, 2015. (link, preprint)


It is a conundrum that agile projects can succeed ‘without requirements’ when weak requirements engineering is a known cause for project failures. While agile development projects often manage well without extensive requirements documentation, test cases are commonly used as requirements. We have investigated this agile practice at three companies in order to understand how test cases can fill the role of requirements. We performed a case study based on twelve interviews performed in a previous study. The findings include a range of benefits and challenges in using test cases for eliciting, validating, verifying, tracing and managing requirements. In addition, we identified three scenarios for applying the practice, namely as a mature practice, as a de facto practice and as part of an agile transition. The findings provide insights into how the role of requirements may be met in agile development including challenges to consider.