c# - Are there any ways to call database data to provide in Unit Testing

Question

This is the Test that i have:

[Test]
public async Task Late_Test()
{
  var options = new DBContextOptionsBuilder<MyContext>()
  .Options;
  
  using(var context = MyContext(options))
  {
    //Act?
  }
    // Assert?
}

This is the service that I am trying to create a test for:

public async Task<int> LatesInMin(Model1 model1, bool isbool) 
{
 //code here
}

The code int the service also needs the data in the foreign keys attached to Model1. Can i call a data from the database and use it as the parameter when i call the service? Or do i have to manually provide that data as well? I tried and using linq causes an error and I searched that you cant use extension methods such as 'Where()' and 'FirstOrDefault()'

Answer 1

For your tests to be isolated and predictable, you need to make sure that you set up and tear down anything associated with the tests. Therefore, you should be seeding a data source either with data alongside your test code, or with data in an associated file which is loaded in before each test. What I'm basically trying to get at is that I think you should pull all of the data you require out of the database, save that into a file somewhere, and then load it in before you run each test. By "load", you could spin up a real database and save the values, or you could use the InMemoryDatabase feature provided by Entity Framework.