refactor(bbb): migrate to MorganGenerator API; consolidate test imports

src/pipelines/bbb_pipeline.py

@@ -59,7 +59,8 @@ def compute_morgan_fingerprint(
             `is_valid_smiles` first if the source is untrusted.
         n_bits: Length of the bit vector. 2048 is the de-facto default
             for downstream scikit-learn classifiers.
-        radius: Morgan radius (2 ≈ ECFP4).
+        radius: Morgan radius (2 ≈ ECFP4). Passed to RDKit's modern
+            MorganGenerator API.
 
     Returns:
         A 1-D `np.ndarray` of length `n_bits` and dtype `uint8`, where
@@ -72,7 +73,8 @@ def compute_morgan_fingerprint(
     if mol is None:
         raise ValueError(f"invalid SMILES: {smiles!r}")
 
-    bit_vect = AllChem.GetMorganFingerprintAsBitVect(mol, radius=radius, nBits=n_bits)
+    generator = AllChem.GetMorganGenerator(radius=radius, fpSize=n_bits)
+    bit_vect = generator.GetFingerprint(mol)
     arr = np.zeros((n_bits,), dtype=np.uint8)
     ConvertToNumpyArray(bit_vect, arr)
     return arr

tests/pipelines/test_bbb_pipeline.py

@@ -3,10 +3,14 @@ from __future__ import annotations
 
 from pathlib import Path
 
+import numpy as np
 import pandas as pd
 import pytest
 
-from src.pipelines.bbb_pipeline import is_valid_smiles
+from src.pipelines.bbb_pipeline import (
+    compute_morgan_fingerprint,
+    is_valid_smiles,
+)
 
 
 FIXTURE = Path(__file__).parent.parent / "fixtures" / "bbbp_sample.csv"
@@ -33,11 +37,6 @@ class TestIsValidSmiles:
         assert is_valid_smiles(math.nan) is False
 
 
-import numpy as np
-
-from src.pipelines.bbb_pipeline import compute_morgan_fingerprint
-
-
 class TestComputeMorganFingerprint:
     def test_returns_numpy_array_of_correct_length(self) -> None:
         fp = compute_morgan_fingerprint("CCCO", n_bits=2048, radius=2)