from __future__ import absolute_import import os import subprocess import virtualenv as _virtualenv from .path import Path # On Python < 3.3 we don't have subprocess.DEVNULL try: DEVNULL = subprocess.DEVNULL except AttributeError: DEVNULL = open(os.devnull, "wb") class VirtualEnvironment(object): """ An abstraction around virtual environments, currently it only uses virtualenv but in the future it could use pyvenv. """ def __init__(self, location, *args, **kwargs): self.location = Path(location) self.pip_source_dir = kwargs.pop("pip_source_dir") self._system_site_packages = kwargs.pop("system_site_packages", False) home, lib, inc, bin = _virtualenv.path_locations(self.location) self.lib = Path(lib) self.bin = Path(bin) super(VirtualEnvironment, self).__init__(*args, **kwargs) def __repr__(self): return "".format(self.location) @classmethod def create(cls, location, clear=False, pip_source_dir=None): obj = cls(location, pip_source_dir=pip_source_dir) obj._create(clear=clear) return obj def _create(self, clear=False): # Create the actual virtual environment _virtualenv.create_environment( self.location, clear=clear, never_download=True, no_pip=True, ) # Install our development version of pip install the virtual # environment cmd = [self.bin.join("python"), "setup.py", "develop"] p = subprocess.Popen( cmd, cwd=self.pip_source_dir, stderr=subprocess.STDOUT, stdout=DEVNULL, ) p.communicate() if p.returncode != 0: raise subprocess.CalledProcessError(p.returncode, cmd[0], output=p.stdout, ) def clear(self): self._create(clear=True) @property def system_site_packages(self): return self._system_site_packages @system_site_packages.setter def system_site_packages(self, value): marker = self.lib.join("no-global-site-packages.txt") if value: marker.rm() else: marker.touch() self._system_site_packages = value