FakeXrmEasy is an invaluable tool for development of Dynamics CRM/365/Dataverse software and using it will make your life as a developer much easier and will undoubtedly help you write more robust, maintainable code. FakeXrmEasy implements an in-memory version of the XRM database and provides mocked version of most of the main methods provided by the IOrganisation service. You may, however, occasionally come across a method which has not been implemented in the library. When you test code which calls one of these methods, your test will fail with a message like this: The organization request type 'Microsoft.Crm.Sdk.Messages.NameOfTheUnimplementedRequest' is not yet supported... but we DO love pull requests so please feel free to submit one! :). This functionality is not available yet. Please consider contributing to the following Git project https://github.com/jordimontana82/fake-xrm-easy by cloning the repository and issuing a pull request."
If you are using EasyRepro to perform automated tests against your Dynamics 365 instance and the account you are using is protected with Multi-Factor Authentication (MFA) you will need to generate an MFA Secret Key in order for your tests to be able to log in.
When writing Unit tests one can focus on two different aspects of the code under test. We can call these two types of test ‘State-based’ and ‘Interaction-based’. The first of these concentrates on the end result achieved by the code under test – ie, what was the result of the code being run, whereas the second focuses on how that result was achieved.