Files
quant/tests/test_factor_attribution.py

60 lines
2.0 KiB
Python

import tempfile
import unittest
from pathlib import Path
from unittest import mock
import pandas as pd
from factor_attribution import load_external_us_factors
class ExternalFactorLoaderTests(unittest.TestCase):
def test_load_external_us_factors_parses_percent_values_and_dates(self):
csv_text = (
"This line is ignored\n"
",Mkt-RF,SMB,HML,RMW,CMA,RF\n"
"20260102,1.00,0.50,-0.25,0.10,-0.05,0.02\n"
"20260105,-0.20,0.10,0.30,-0.15,0.05,0.02\n"
"\n"
)
with tempfile.TemporaryDirectory() as tmpdir:
with mock.patch(
"factor_attribution._download_kf_zip_bytes",
return_value=csv_text.encode("utf-8"),
):
factors = load_external_us_factors(cache_dir=Path(tmpdir))
self.assertListEqual(
list(factors.columns),
["MKT_RF", "SMB", "HML", "RMW", "CMA", "RF"],
)
self.assertAlmostEqual(factors.iloc[0]["MKT_RF"], 0.01)
self.assertAlmostEqual(factors.iloc[0]["RF"], 0.0002)
self.assertEqual(str(factors.index[0].date()), "2026-01-02")
def test_load_external_us_factors_falls_back_to_cache_when_download_fails(self):
cached = pd.DataFrame(
{
"MKT_RF": [0.01],
"SMB": [0.0],
"HML": [0.0],
"RMW": [0.0],
"CMA": [0.0],
"RF": [0.0001],
},
index=pd.to_datetime(["2026-01-02"]),
)
with tempfile.TemporaryDirectory() as tmpdir:
cache_dir = Path(tmpdir)
cached.to_csv(cache_dir / "ff5_us_daily.csv")
with mock.patch(
"factor_attribution._download_kf_zip_bytes",
side_effect=RuntimeError("boom"),
):
factors = load_external_us_factors(cache_dir=cache_dir)
self.assertEqual(len(factors), 1)
self.assertAlmostEqual(factors.iloc[0]["MKT_RF"], 0.01)