105 lines
3.4 KiB
Python
105 lines
3.4 KiB
Python
import logging
|
|
import os
|
|
import re
|
|
import site
|
|
import sys
|
|
from typing import List, Optional
|
|
|
|
logger = logging.getLogger(__name__)
|
|
_INCLUDE_SYSTEM_SITE_PACKAGES_REGEX = re.compile(
|
|
r"include-system-site-packages\s*=\s*(?P<value>true|false)"
|
|
)
|
|
|
|
|
|
def _running_under_venv() -> bool:
|
|
"""Checks if sys.base_prefix and sys.prefix match.
|
|
|
|
This handles PEP 405 compliant virtual environments.
|
|
"""
|
|
return sys.prefix != getattr(sys, "base_prefix", sys.prefix)
|
|
|
|
|
|
def _running_under_regular_virtualenv() -> bool:
|
|
"""Checks if sys.real_prefix is set.
|
|
|
|
This handles virtual environments created with pypa's virtualenv.
|
|
"""
|
|
# pypa/virtualenv case
|
|
return hasattr(sys, "real_prefix")
|
|
|
|
|
|
def running_under_virtualenv() -> bool:
|
|
"""Return True if we're running inside a virtualenv, False otherwise."""
|
|
return _running_under_venv() or _running_under_regular_virtualenv()
|
|
|
|
|
|
def _get_pyvenv_cfg_lines() -> Optional[List[str]]:
|
|
"""Reads {sys.prefix}/pyvenv.cfg and returns its contents as list of lines
|
|
|
|
Returns None, if it could not read/access the file.
|
|
"""
|
|
pyvenv_cfg_file = os.path.join(sys.prefix, "pyvenv.cfg")
|
|
try:
|
|
# Although PEP 405 does not specify, the built-in venv module always
|
|
# writes with UTF-8. (pypa/pip#8717)
|
|
with open(pyvenv_cfg_file, encoding="utf-8") as f:
|
|
return f.read().splitlines() # avoids trailing newlines
|
|
except OSError:
|
|
return None
|
|
|
|
|
|
def _no_global_under_venv() -> bool:
|
|
"""Check `{sys.prefix}/pyvenv.cfg` for system site-packages inclusion
|
|
|
|
PEP 405 specifies that when system site-packages are not supposed to be
|
|
visible from a virtual environment, `pyvenv.cfg` must contain the following
|
|
line:
|
|
|
|
include-system-site-packages = false
|
|
|
|
Additionally, log a warning if accessing the file fails.
|
|
"""
|
|
cfg_lines = _get_pyvenv_cfg_lines()
|
|
if cfg_lines is None:
|
|
# We're not in a "sane" venv, so assume there is no system
|
|
# site-packages access (since that's PEP 405's default state).
|
|
logger.warning(
|
|
"Could not access 'pyvenv.cfg' despite a virtual environment "
|
|
"being active. Assuming global site-packages is not accessible "
|
|
"in this environment."
|
|
)
|
|
return True
|
|
|
|
for line in cfg_lines:
|
|
match = _INCLUDE_SYSTEM_SITE_PACKAGES_REGEX.match(line)
|
|
if match is not None and match.group("value") == "false":
|
|
return True
|
|
return False
|
|
|
|
|
|
def _no_global_under_regular_virtualenv() -> bool:
|
|
"""Check if "no-global-site-packages.txt" exists beside site.py
|
|
|
|
This mirrors logic in pypa/virtualenv for determining whether system
|
|
site-packages are visible in the virtual environment.
|
|
"""
|
|
site_mod_dir = os.path.dirname(os.path.abspath(site.__file__))
|
|
no_global_site_packages_file = os.path.join(
|
|
site_mod_dir,
|
|
"no-global-site-packages.txt",
|
|
)
|
|
return os.path.exists(no_global_site_packages_file)
|
|
|
|
|
|
def virtualenv_no_global() -> bool:
|
|
"""Returns a boolean, whether running in venv with no system site-packages."""
|
|
# PEP 405 compliance needs to be checked first since virtualenv >=20 would
|
|
# return True for both checks, but is only able to use the PEP 405 config.
|
|
if _running_under_venv():
|
|
return _no_global_under_venv()
|
|
|
|
if _running_under_regular_virtualenv():
|
|
return _no_global_under_regular_virtualenv()
|
|
|
|
return False
|