public void BankAccount_GetByCustomerId() { // Arrange _dbContext.Customers.Add(new Customer { Name = Guid.NewGuid().ToString(), Surname = Guid.NewGuid().ToString(), DateCreated = DateTime.UtcNow }); _dbContext.SaveChanges(); var bankAccountRepository = new BankAccountRepository(_dbContext); _dbContext.BankAccounts.Add(new BankAccount { CustomerId = 1 }); _dbContext.SaveChanges(); // Act var bankAccount = bankAccountRepository.GetByCustomerId(1); // Assert Assert.NotNull(bankAccount); }