import torch
from hilbert_mi.scalable import HilbertOperatorClassifier

def test_forward_and_backward():
    m=HilbertOperatorClassifier(width=8,depth=1,modes=4,rank=2)
    x=torch.randn(2,3,16,16); y=m(x)
    assert y.shape==(2,10); y.sum().backward()
    assert all(p.grad is not None for p in m.parameters())