  In order to properly test software, test data of a certain quality is needed.
However, useful test data is often unavailable: Existing or hand-crafted data
might not be diverse enough to enable desired test cases. Furthermore, using
production data might be prohibited due to security or privacy concerns or
other regulations. At the same time, existing tools for test data generation
are often limited. In this paper, we evaluate to what extent constraint logic
programming can be used to generate test data, focussing on strings in
particular. To do so, we introduce a prototypical CLP solver over string
constraints. As case studies, we use it to generate IBAN numbers and calender
dates.
