test(starknet_os): add small fft regression test

[dorimedini-starkware]

No description provided.

[reviewable-StarkWare]

This change is 

[dorimedini-starkware]

• feat(starknet_os): use ark_poly FFT implementation #4985
• feat(starknet_os): inline ark_poly bit_reversal algorithm #5110
• test(starknet_os): fft regression #4984
• feat(starknet_os): use BigUint instead of BigInt in KZG area #4922
• refactor(starknet_os): inner_fft implementation without cloning the slices #4896
• test(starknet_os): add small fft regression test #4895 👈 (View in Graphite)
• feat(starknet_os): implement hint store_da_segment #4880
• feat(starknet_os): add the da_segment field to the hint processor #4879
• feat(starknet_os): integrate polynomial_coefficients_to_kzg_commitment #4878
• feat(starknet_os): integrate split_commitment and test #4877
• feat(starknet_os): integrate blob_to_kzg_commitment and add trusted setup data #4876
• feat(starknet_os): integrate polynomial_coefficients_to_blob #4875
• feat(starknet_os): integrate to_bytes and serialize_blob #4874
• feat(starknet_os): integrate the fft function #4873
• feat(starknet_os): integrate the inner_fft function #4872
• feat(starknet_os): split KZG module into implementation and utils #4871
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[aner-starkware]

crates/starknet_os/src/hints/hint_implementation/kzg/test.rs line 29 at r1 (raw file):

    let generator = BigInt::from(3);
    let coeffs: Vec<BigInt> = [0, 1, 2, 3].into_iter().map(BigInt::from).collect();
    let expected_eval: Vec<BigInt> = (if bit_reversed { [6, 15, 9, 4] } else { [6, 9, 15, 4] })

Were these taken from somewhere, or did you compute them?

Code quote:

let expected_eval: Vec<BigInt> = (if bit_reversed { [6, 15, 9, 4] } else { [6, 9, 15, 4] })

[aner-starkware]

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @amosStarkware, @dorimedini-starkware, and @nimrod-starkware)

[dorimedini-starkware]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @amosStarkware, @aner-starkware, and @nimrod-starkware)

---

crates/starknet_os/src/hints/hint_implementation/kzg/test.rs line 29 at r1 (raw file):

Previously, aner-starkware wrote…

Were these taken from somewhere, or did you compute them?

I ran the code before PR 4896 to get the values, then used this test to find the bug in 4896. I assumed that if (a) the logic was copied from moonsong and (b) I didn't refactor yet, the values I get are correct.

[aner-starkware]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @amosStarkware and @nimrod-starkware)

---

crates/starknet_os/src/hints/hint_implementation/kzg/test.rs line 29 at r1 (raw file):

Previously, dorimedini-starkware wrote…

I ran the code before PR 4896 to get the values, then used this test to find the bug in 4896. I assumed that if (a) the logic was copied from moonsong and (b) I didn't refactor yet, the values I get are correct.

Maybe consider copying the naive computation from the test_fft instead? (Or even better, make it a fn and call it).
I can't say I'm a fan of magic numbers that come from nowhere, but unblocking.

[dorimedini-starkware]

Reviewable status: 0 of 1 files reviewed, all discussions resolved (waiting on @amosStarkware, @aner-starkware, and @nimrod-starkware)

---

crates/starknet_os/src/hints/hint_implementation/kzg/test.rs line 29 at r1 (raw file):

Previously, aner-starkware wrote…

Maybe consider copying the naive computation from the test_fft instead? (Or even better, make it a fn and call it).
I can't say I'm a fan of magic numbers that come from nowhere, but unblocking.

the point of the small_fft_regression test is to not copy test_fft, as it generates huge input/output pairs that are unusable for debugging.
test_fft is still a good test for the change I made

[aner-starkware]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @amosStarkware and @nimrod-starkware)