SP/lib/python3.7/site-packages/pip-10.0.1-py3.7.egg/pip/_internal/build_env.py
Saturneic 064f602b1a Add.
2018-10-25 23:33:13 +08:00

93 lines
2.6 KiB
Python

"""Build Environment used for isolation during sdist building
"""
import os
from distutils.sysconfig import get_python_lib
from sysconfig import get_paths
from pip._internal.utils.temp_dir import TempDirectory
class BuildEnvironment(object):
"""Creates and manages an isolated environment to install build deps
"""
def __init__(self, no_clean):
self._temp_dir = TempDirectory(kind="build-env")
self._no_clean = no_clean
@property
def path(self):
return self._temp_dir.path
def __enter__(self):
self._temp_dir.create()
self.save_path = os.environ.get('PATH', None)
self.save_pythonpath = os.environ.get('PYTHONPATH', None)
self.save_nousersite = os.environ.get('PYTHONNOUSERSITE', None)
install_scheme = 'nt' if (os.name == 'nt') else 'posix_prefix'
install_dirs = get_paths(install_scheme, vars={
'base': self.path,
'platbase': self.path,
})
scripts = install_dirs['scripts']
if self.save_path:
os.environ['PATH'] = scripts + os.pathsep + self.save_path
else:
os.environ['PATH'] = scripts + os.pathsep + os.defpath
# Note: prefer distutils' sysconfig to get the
# library paths so PyPy is correctly supported.
purelib = get_python_lib(plat_specific=0, prefix=self.path)
platlib = get_python_lib(plat_specific=1, prefix=self.path)
if purelib == platlib:
lib_dirs = purelib
else:
lib_dirs = purelib + os.pathsep + platlib
if self.save_pythonpath:
os.environ['PYTHONPATH'] = lib_dirs + os.pathsep + \
self.save_pythonpath
else:
os.environ['PYTHONPATH'] = lib_dirs
os.environ['PYTHONNOUSERSITE'] = '1'
return self.path
def __exit__(self, exc_type, exc_val, exc_tb):
if not self._no_clean:
self._temp_dir.cleanup()
def restore_var(varname, old_value):
if old_value is None:
os.environ.pop(varname, None)
else:
os.environ[varname] = old_value
restore_var('PATH', self.save_path)
restore_var('PYTHONPATH', self.save_pythonpath)
restore_var('PYTHONNOUSERSITE', self.save_nousersite)
def cleanup(self):
self._temp_dir.cleanup()
class NoOpBuildEnvironment(BuildEnvironment):
"""A no-op drop-in replacement for BuildEnvironment
"""
def __init__(self, no_clean):
pass
def __enter__(self):
pass
def __exit__(self, exc_type, exc_val, exc_tb):
pass
def cleanup(self):
pass