Many improvement are done in Microsoft Dynamics 365 for Finance and Operations, Enterprise edition to help developer or test engineer author automated test cases. Developers can write unit test code using SysTest Framework and catch error early on the development process and improve quality. A custom unit test adapter is available in Visual Studio. This adapter lets test authors use the standard Test Explorer window in Visual Studio to schedule X++ tests and analyze test results. Developers can author tests by using SysTestAdaptor. You can also generate test code from task recorder recordings. These test cases can then be added to build systems for validations. For details steps on how to author unit test follow the Microsoft documentation link stated which is as follows:

https://docs.microsoft.com/en-us/dynamics365/unified-operations/dev-itpro/perf-test/testing-validation