EIP4844: compute_kzg_proof() now takes bytes as input (#3219)

specs/eip4844/polynomial-commitments.md

@@ -35,6 +35,7 @@
     - [`verify_kzg_proof`](#verify_kzg_proof)
     - [`verify_kzg_proof_impl`](#verify_kzg_proof_impl)
     - [`compute_kzg_proof`](#compute_kzg_proof)
+    - [`compute_kzg_proof_impl`](#compute_kzg_proof_impl)
     - [`compute_aggregated_poly_and_commitment`](#compute_aggregated_poly_and_commitment)
     - [`compute_aggregate_kzg_proof`](#compute_aggregate_kzg_proof)
     - [`verify_aggregate_kzg_proof`](#verify_aggregate_kzg_proof)
@@ -370,12 +371,23 @@ def verify_kzg_proof_impl(polynomial_kzg: KZGCommitment,
 #### `compute_kzg_proof`
 
 ```python
-def compute_kzg_proof(polynomial: Polynomial, z: BLSFieldElement) -> KZGProof:
+def compute_kzg_proof(blob: Blob, z: Bytes32) -> KZGProof:
     """
-    Compute KZG proof at point `z` with `polynomial` being in evaluation form.
+    Compute KZG proof at point `z` for the polynomial represented by `blob`.
     Do this by computing the quotient polynomial in evaluation form: q(x) = (p(x) - p(z)) / (x - z).
     Public method.
     """
+    polynomial = blob_to_polynomial(blob)
+    return compute_kzg_proof_impl(polynomial, bytes_to_bls_field(z))
+```
+
+#### `compute_kzg_proof_impl`
+
+```python
+def compute_kzg_proof_impl(polynomial: Polynomial, z: BLSFieldElement) -> KZGProof:
+    """
+    Helper function for compute_kzg_proof() and compute_aggregate_kzg_proof().
+    """
     y = evaluate_polynomial_in_evaluation_form(polynomial, z)
     polynomial_shifted = [BLSFieldElement((int(p) - int(y)) % BLS_MODULUS) for p in polynomial]
 
@@ -430,7 +442,7 @@ def compute_aggregate_kzg_proof(blobs: Sequence[Blob]) -> KZGProof:
         blobs,
         commitments
     )
-    return compute_kzg_proof(aggregated_poly, evaluation_challenge)
+    return compute_kzg_proof_impl(aggregated_poly, evaluation_challenge)
 ```
 
 #### `verify_aggregate_kzg_proof`

tests/core/pyspec/eth2spec/test/eip4844/unittests/polynomial_commitments/test_polynomial_commitments.py

@@ -18,7 +18,7 @@ def test_verify_kzg_proof(spec, state):
     blob = get_sample_blob(spec)
     commitment = spec.blob_to_kzg_commitment(blob)
     polynomial = spec.blob_to_polynomial(blob)
-    proof = spec.compute_kzg_proof(polynomial, x)
+    proof = spec.compute_kzg_proof_impl(polynomial, x)
 
     y = spec.evaluate_polynomial_in_evaluation_form(polynomial, x)
     assert spec.verify_kzg_proof_impl(commitment, x, y, proof)