Input to holomorphic_grad is not complex

[zhengqigao]

Hi, I have a test case for the holomorphic_grad() function.

def trial_func(x):
    return (x + 1.0j) * (x + 1.0j)

my_grad  = holomorphic_grad(trial_func)
print("grad 1 is:", my_grad(1.))
print("grad 2 is:", my_grad(-(1.j)**2))

It prints out

grad 1 is: 2.0
grad 2 is: (2+2j)

with a warning 'Input to holomorphic_grad is not complex' for the first case. I am a bit confused about the logic here. Intuitively, I think they should return the same results? Does this mean we need to make a pure real number written in the format of a complex number?

Thanks.