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# mypy: allow-untyped-defs
import logging
import os
import shutil
import site
import sys
import sysconfig
from shutil import which
# The `pkg_resources` module is provided by `setuptools`, which is itself a
# dependency of `virtualenv`. Tolerate its absence so that this module may be
# evaluated when that module is not available. Because users may not recognize
# the `pkg_resources` module by name, raise a more descriptive error if it is
# referenced during execution.
try:
import pkg_resources as _pkg_resources
get_pkg_resources = lambda: _pkg_resources
except ImportError:
def get_pkg_resources():
raise ValueError("The Python module `virtualenv` is not installed.")
from tools.wpt.utils import call
logger = logging.getLogger(__name__)
class Virtualenv:
def __init__(self, path, skip_virtualenv_setup):
self.path = path
self.skip_virtualenv_setup = skip_virtualenv_setup
if not skip_virtualenv_setup:
self.virtualenv = [sys.executable, "-m", "venv"]
self._working_set = None
@property
def exists(self):
# We need to check also for lib_path because different python versions
# create different library paths.
return os.path.isdir(self.path) and os.path.isdir(self.lib_path)
@property
def broken_link(self):
python_link = os.path.join(self.path, ".Python")
return os.path.lexists(python_link) and not os.path.exists(python_link)
def create(self):
if os.path.exists(self.path):
shutil.rmtree(self.path, ignore_errors=True)
self._working_set = None
call(*self.virtualenv, self.path)
def get_paths(self):
"""Wrapper around sysconfig.get_paths(), returning the appropriate paths for the env."""
if "venv" in sysconfig.get_scheme_names():
# This should always be used on Python 3.11 and above.
scheme = "venv"
elif os.name == "nt":
# This matches nt_venv, unless sysconfig has been modified.
scheme = "nt"
elif os.name == "posix":
# This matches posix_venv, unless sysconfig has been modified.
scheme = "posix_prefix"
elif sys.version_info >= (3, 10):
# Using the default scheme is somewhat fragile, as various Python
# distributors (e.g., what Debian and Fedora package, and what Xcode
# includes) change the default scheme away from the upstream
# defaults, but it's about as good as we can do.
scheme = sysconfig.get_default_scheme()
else:
# This is explicitly documented as having previously existed in the 3.10
# docs, and has existed since CPython 2.7 and 3.1 (but not 3.0).
scheme = sysconfig._get_default_scheme()
vars = {
"base": self.path,
"platbase": self.path,
"installed_base": self.path,
"installed_platbase": self.path,
}
return sysconfig.get_paths(scheme, vars)
@property
def bin_path(self):
return self.get_paths()["scripts"]
@property
def pip_path(self):
path = which("pip3", path=self.bin_path)
if path is None:
path = which("pip", path=self.bin_path)
if path is None:
raise ValueError("pip3 or pip not found")
return path
@property
def lib_path(self):
# We always return platlib here, even if it differs to purelib, because we can
# always install pure-Python code into the platlib safely too. It's also very
# unlikely to differ for a venv.
return self.get_paths()["platlib"]
@property
def working_set(self):
if not self.exists:
raise ValueError("trying to read working_set when venv doesn't exist")
if self._working_set is None:
self._working_set = get_pkg_resources().WorkingSet((self.lib_path,))
return self._working_set
def activate(self):
if sys.platform == "darwin":
# The default Python on macOS sets a __PYVENV_LAUNCHER__ environment
# variable which affects invocation of python (e.g. via pip) in a
# virtualenv. Unset it if present to avoid this. More background:
os.environ.pop("__PYVENV_LAUNCHER__", None)
paths = self.get_paths()
# Setup the path and site packages as if we'd launched with the virtualenv active
bin_dir = paths["scripts"]
os.environ["PATH"] = os.pathsep.join([bin_dir] + os.environ.get("PATH", "").split(os.pathsep))
# While not required (`./venv/bin/python3` won't set it, but
# `source ./venv/bin/activate && python3` will), we have historically set this.
os.environ["VIRTUAL_ENV"] = self.path
prev_length = len(sys.path)
# Add the venv library paths as sitedirs.
for key in ["purelib", "platlib"]:
site.addsitedir(paths[key])
# Rearrange the path
sys.path[:] = sys.path[prev_length:] + sys.path[0:prev_length]
# Change prefixes, similar to what initconfig/site does for venvs.
sys.exec_prefix = self.path
sys.prefix = self.path
def start(self):
if not self.exists or self.broken_link:
self.create()
self.activate()
def install(self, *requirements):
try:
self.working_set.require(*requirements)
except Exception:
pass
else:
return
# `--prefer-binary` guards against race conditions when installation
# occurs while packages are in the process of being published.
call(self.pip_path, "install", "--prefer-binary", *requirements)
def install_requirements(self, *requirements_paths):
install = []
# Check which requirements are already satisfied, to skip calling pip
# at all in the case that we've already installed everything, and to
# minimise the installs in other cases.
for requirements_path in requirements_paths:
with open(requirements_path) as f:
try:
self.working_set.require(f.read())
except Exception:
install.append(requirements_path)
if install:
# `--prefer-binary` guards against race conditions when installation
# occurs while packages are in the process of being published.
cmd = [self.pip_path, "install", "--prefer-binary"]
for path in install:
cmd.extend(["-r", path])
call(*cmd)