using Moq to mock a Repository and test a user create operation

CreateUserHandlerTests.cs

using Xunit;
using Moq;

public class CreateUserHandlerTests
{
  [Fact]
  public async Task should_create_user_when_command_valid()
  {
      var command = new CreateUser(id: Guid.NewGuid(), username: "loremipsum", email: "lorem@ipsum.com", firstname: "lorem", lastname:"ipsum");

      var mockRepo = new Mock<IRepository<Infrastructure.Entities.User>>();

      var mockDbContext = new Mock<IDbContext>();
      mockDbContext.Setup(db => db.Users).Returns(mockRepo.Object);

      var sut = new CreateUserHandler(mockDbContext.Object);
      await sut.Handle(command);

      mockRepo.Verify(m => m.InsertOneAsync(It.IsAny<Infrastructure.Entities.User>()), Times.Once());
   }
}