103 lines
4.2 KiB
Python
103 lines
4.2 KiB
Python
"""Patches that are applied at runtime to the virtual environment."""
|
|
|
|
from __future__ import annotations
|
|
|
|
import os
|
|
import sys
|
|
from contextlib import suppress
|
|
|
|
VIRTUALENV_PATCH_FILE = os.path.join(__file__)
|
|
|
|
|
|
def patch_dist(dist):
|
|
"""
|
|
Distutils allows user to configure some arguments via a configuration file:
|
|
https://docs.python.org/3/install/index.html#distutils-configuration-files.
|
|
|
|
Some of this arguments though don't make sense in context of the virtual environment files, let's fix them up.
|
|
""" # noqa: D205
|
|
# we cannot allow some install config as that would get packages installed outside of the virtual environment
|
|
old_parse_config_files = dist.Distribution.parse_config_files
|
|
|
|
def parse_config_files(self, *args, **kwargs):
|
|
result = old_parse_config_files(self, *args, **kwargs)
|
|
install = self.get_option_dict("install")
|
|
|
|
if "prefix" in install: # the prefix governs where to install the libraries
|
|
install["prefix"] = VIRTUALENV_PATCH_FILE, os.path.abspath(sys.prefix)
|
|
for base in ("purelib", "platlib", "headers", "scripts", "data"):
|
|
key = f"install_{base}"
|
|
if key in install: # do not allow global configs to hijack venv paths
|
|
install.pop(key, None)
|
|
return result
|
|
|
|
dist.Distribution.parse_config_files = parse_config_files
|
|
|
|
|
|
# Import hook that patches some modules to ignore configuration values that break package installation in case
|
|
# of virtual environments.
|
|
_DISTUTILS_PATCH = "distutils.dist", "setuptools.dist"
|
|
# https://docs.python.org/3/library/importlib.html#setting-up-an-importer
|
|
|
|
|
|
class _Finder:
|
|
"""A meta path finder that allows patching the imported distutils modules."""
|
|
|
|
fullname = None
|
|
|
|
# lock[0] is threading.Lock(), but initialized lazily to avoid importing threading very early at startup,
|
|
# because there are gevent-based applications that need to be first to import threading by themselves.
|
|
# See https://github.com/pypa/virtualenv/issues/1895 for details.
|
|
lock = [] # noqa: RUF012
|
|
|
|
def find_spec(self, fullname, path, target=None): # noqa: ARG002
|
|
if fullname in _DISTUTILS_PATCH and self.fullname is None:
|
|
# initialize lock[0] lazily
|
|
if len(self.lock) == 0:
|
|
import threading
|
|
|
|
lock = threading.Lock()
|
|
# there is possibility that two threads T1 and T2 are simultaneously running into find_spec,
|
|
# observing .lock as empty, and further going into hereby initialization. However due to the GIL,
|
|
# list.append() operation is atomic and this way only one of the threads will "win" to put the lock
|
|
# - that every thread will use - into .lock[0].
|
|
# https://docs.python.org/3/faq/library.html#what-kinds-of-global-value-mutation-are-thread-safe
|
|
self.lock.append(lock)
|
|
|
|
from functools import partial
|
|
from importlib.util import find_spec
|
|
|
|
with self.lock[0]:
|
|
self.fullname = fullname
|
|
try:
|
|
spec = find_spec(fullname, path)
|
|
if spec is not None:
|
|
# https://www.python.org/dev/peps/pep-0451/#how-loading-will-work
|
|
is_new_api = hasattr(spec.loader, "exec_module")
|
|
func_name = "exec_module" if is_new_api else "load_module"
|
|
old = getattr(spec.loader, func_name)
|
|
func = self.exec_module if is_new_api else self.load_module
|
|
if old is not func:
|
|
with suppress(AttributeError): # C-Extension loaders are r/o such as zipimporter with <3.7
|
|
setattr(spec.loader, func_name, partial(func, old))
|
|
return spec
|
|
finally:
|
|
self.fullname = None
|
|
return None
|
|
|
|
@staticmethod
|
|
def exec_module(old, module):
|
|
old(module)
|
|
if module.__name__ in _DISTUTILS_PATCH:
|
|
patch_dist(module)
|
|
|
|
@staticmethod
|
|
def load_module(old, name):
|
|
module = old(name)
|
|
if module.__name__ in _DISTUTILS_PATCH:
|
|
patch_dist(module)
|
|
return module
|
|
|
|
|
|
sys.meta_path.insert(0, _Finder())
|