TDGD: Test Driven Game Development

Ludii is a General Game System for playing, analyzing, and designing board games through its Game Description Language. This language is based on over 700 ludemes, which are high-level constructs representing boards, pieces, and rules. While ludemes provide a comprehensive vocabulary for describing games, they also pose a steep learning curve, particularly for Ludii’s many non-technical users such as historians interested in traditional and ancient games. The absence of a dedicated testing framework further increases the difficulty of encoding new games, as validation currently relies only on limited syntax checks or game trials, which provide few guarantees of correctness and robustness. To address these challenges, this work explores the adaptation of the well-established Test-Driven Development methodology to game design, introducing a Test-Driven Game Development approach. A prototype testing framework was developed as a dashboard integrated into the Ludii interface, supported by a database of generic tests to evaluate its effectiveness. The framework follows a Model-View-Controller architecture, ensuring both reliability and extensibility. Tests were classified into two categories: static tests, executed once when a game is loaded, and dynamic tests, executed during gameplay to validate rules, states, and outcomes. The framework was validated on 1,127 games with 7,889 test executions across seven static test types. It achieved a success rate of 36.68%, with 83.29% of failures attributable to deliberately excluded features, confirming the soundness of the test logic. These results demonstrate the robustness of the dashboard and the generality of the test suite. They establish a foundation for reliable, automated validation within Ludii, bridging formal software engineering practices with game design and enabling the development of more robust, maintainable, and accessible board games.