import csv,json
from pathlib import Path
p=Path(__file__).parent
expected=json.loads((p/'bom-input.json').read_bytes().decode('utf-8-sig'))
with (p/'bom-output.csv').open(encoding='utf-8',newline='') as f:actual=list(csv.DictReader(f))
assert actual==expected
assert actual[1]['note']=='inside\ufefffield'
print('Two ordered records match; U+FEFF inside B2 remains unchanged.')