TDDHQ: Achieving Higher Quality Testing in Test Driven Development

Test driven development (TDD) appears not to be immune to positive test bias effects, as we observed in several empirical studies. In these studies, developers created a significantly larger set of positive tests, but at the same time the number of defects detected with negative tests is significantly higher than those detected by positive ones. In this paper we propose the concept of TDDHQ which is aimed at achieving higher quality of testing in TDD by augmenting the standard TDD with suitable test design techniques. To exemplify this concept, we present combining equivalence partitioning test design technique together with the TDD, for the purpose of improving design of test cases. Initial evaluation of this approach showed a noticeable improvement in the quality of test cases created by developers utilising TDDHQ approach.