TESTed - An educational testing framework with language-agnostic test suites for programming exercises.

In educational contexts, automated assessment tools (AAT) are commonly used to provide formative feedback on programming exercises. However, designing exercises for AAT remains a laborious task or imposes limitations on the exercises. Most AAT use either output comparison, where the generated output is compared against an expected output, or unit testing, where the tool has access to the code of the submission under test. While output comparison has the advantage of being programming language independent, the testing capabilities are limited to the output. Conversely, unit testing can generate more granular feedback, but is tightly coupled with the programming language of the submission. In this paper, we introduce TESTed, which enables the best of both worlds: combining the granular feedback of unit testing with the programming language independence of output comparison. Educators can save time by designing exercises that can be used across programming languages. Finally, we report on using TESTed in educational practice.