What is a specially written routine that generates appropriate test data for testing before module completion called?

The term that refers to a specially written routine designed to generate appropriate test data for testing purposes before a module is completed is known as a driver. In software development, drivers are used to simulate the behavior of components that a particular module interacts with. This is especially useful during early stages of development when the actual modules may not be fully implemented yet.

Drivers facilitate testing by providing necessary inputs and enabling a software module to be executed in isolation. They help ensure that the testing process can continue even when not all parts of the software system are developed, allowing developers to verify individual modules for correctness and functionality. This is crucial for maintaining a robust development workflow, as it enables earlier detection of bugs and issues.

Other terms related to the process of testing include stubs and test cases, but they serve different purposes in the testing cycle. Stubs are used to mimic the operation of modules that the module under test interacts with, whereas test cases are specific conditions or inputs used to evaluate whether the software behaves as expected during testing. Mock-ups typically refer to visual representations or prototypes of the user interface rather than being involved directly in the testing of code functionality.