scikit-learn/sklearn/conftest.py

47 lines
1.3 KiB
Python

import os
import pytest
from threadpoolctl import threadpool_limits
from sklearn.utils._openmp_helpers import _openmp_effective_n_threads
@pytest.fixture(scope='function')
def pyplot():
"""Setup and teardown fixture for matplotlib.
This fixture checks if we can import matplotlib. If not, the tests will be
skipped. Otherwise, we setup matplotlib backend and close the figures
after running the functions.
Returns
-------
pyplot : module
The ``matplotlib.pyplot`` module.
"""
matplotlib = pytest.importorskip('matplotlib')
matplotlib.use('agg')
pyplot = pytest.importorskip('matplotlib.pyplot')
yield pyplot
pyplot.close('all')
def pytest_runtest_setup(item):
"""Set the number of openmp threads based on the number of workers
xdist is using to prevent oversubscription.
Parameters
----------
item : pytest item
item to be processed
"""
try:
xdist_worker_count = int(os.environ['PYTEST_XDIST_WORKER_COUNT'])
except KeyError:
# raises when pytest-xdist is not installed
return
openmp_threads = _openmp_effective_n_threads()
threads_per_worker = max(openmp_threads // xdist_worker_count, 1)
threadpool_limits(threads_per_worker, user_api='openmp')