public void AddChiefEmployee_ShouldReturnFalse(string login, decimal salary, decimal bonus)
{
//arrange
ChiefEmployee employee = new ChiefEmployee(login, salary, bonus);
var employeeRepositoryMock = new Mock <IEmployeeRepository>();
employeeRepositoryMock.Setup(x
=> x.AddChief(It.Is <ChiefEmployee>(y
=> y == employee)));
var service = new EmployeeService(employeeRepositoryMock.Object);
//act
var result = service.AddChiefEmployee(employee);
//assert
employeeRepositoryMock.Verify(x
=> x.AddChief(employee), Times.Never);
Assert.IsFalse(result);
}