public async Task AddRolesToUsers() { // Arrange var userId = 3; var ids = context .Roles .Where(r => r.RoleLevel != RoleLevel.NULL) .ToList() .Select(r => r.Id) .ToList(); var userRoleIds = context .Roles .Where(r => r.Users.Any(ur => ur.UserId == userId)) .ToList() .Select(r => r.Id) .ToList(); ids = ids.RemoveSubList(userRoleIds).ToList(); // Act var result = await sut.AddRoles(userId, ids); // Assert Assert.That(result.Success, Is.True); }