Summary

Tree structures are useful for organizing test cases so that the proper set of tests can easily be selected for a given set of changes to the game code. Each downstream node represents a set of tests with a more specific purpose and scope than the nodes above.

Additionally, tests can reflect tree-like relationships that exist between game functions and elements. The behavior of these structures is tested by exercising the values along the various possible paths from the start of the tree to each of the terminal nodes.

Finally, test trees can be designed to improve understanding of a complex game feature and bring order to a potentially chaotic function, especially regarding interactions with other game rules, elements, and functions. The tree is constructed by progressively decomposing the feature until the bottom nodes identify specific actions to perform or elements to use during testing.