ProgramBuddy

Unit test is executed in less than half of the second. When we have an integration test which is using a repository that is connected to a database it will be executed in several seconds. With a repository, that has an implementation in-memory, tests will be executed faster. There are also other benefits.

Can entities have only attributes that are data values and aren’t collections? What is alternative?

You have a test coverage 90% or more but not 100%. You have tests that cover all exceptional cases. What about code that is not covered with tests?