mapnik/scons/scons-local-4.1.0/SCons/Platform/virtualenv.py
2021-03-05 10:18:26 +00:00

115 lines
3.8 KiB
Python

# MIT License
#
# Copyright The SCons Foundation
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""'Platform" support for a Python virtualenv."""
import os
import sys
import SCons.Util
virtualenv_enabled_by_default = False
def _enable_virtualenv_default():
return SCons.Util.get_os_env_bool('SCONS_ENABLE_VIRTUALENV', virtualenv_enabled_by_default)
def _ignore_virtualenv_default():
return SCons.Util.get_os_env_bool('SCONS_IGNORE_VIRTUALENV', False)
enable_virtualenv = _enable_virtualenv_default()
ignore_virtualenv = _ignore_virtualenv_default()
virtualenv_variables = ['VIRTUAL_ENV', 'PIPENV_ACTIVE']
def _running_in_virtualenv():
"""Returns True if scons is executed within a virtualenv"""
# see https://stackoverflow.com/a/42580137
return (hasattr(sys, 'real_prefix') or
(hasattr(sys, 'base_prefix') and sys.base_prefix != sys.prefix))
def _is_path_in(path, base):
"""Returns true if **path** is located under the **base** directory."""
if not path or not base: # empty path may happen, base too
return False
rp = os.path.relpath(path, base)
return (not rp.startswith(os.path.pardir)) and (not rp == os.path.curdir)
def _inject_venv_variables(env):
if 'ENV' not in env:
env['ENV'] = {}
ENV = env['ENV']
for name in virtualenv_variables:
try:
ENV[name] = os.environ[name]
except KeyError:
pass
def _inject_venv_path(env, path_list=None):
"""Modify environment such that SCons will take into account its virtualenv
when running external tools."""
if path_list is None:
path_list = os.getenv('PATH')
env.PrependENVPath('PATH', select_paths_in_venv(path_list))
def select_paths_in_venv(path_list):
"""Returns a list of paths from **path_list** which are under virtualenv's
home directory."""
if SCons.Util.is_String(path_list):
path_list = path_list.split(os.path.pathsep)
# Find in path_list the paths under the virtualenv's home
return [path for path in path_list if IsInVirtualenv(path)]
def ImportVirtualenv(env):
"""Copies virtualenv-related environment variables from OS environment
to ``env['ENV']`` and prepends virtualenv's PATH to ``env['ENV']['PATH']``.
"""
_inject_venv_variables(env)
_inject_venv_path(env)
def Virtualenv():
"""Returns path to the virtualenv home if scons is executing within a
virtualenv or None, if not."""
if _running_in_virtualenv():
return sys.prefix
return None
def IsInVirtualenv(path):
"""Returns True, if **path** is under virtualenv's home directory. If not,
or if we don't use virtualenv, returns False."""
return _is_path_in(path, Virtualenv())
# Local Variables:
# tab-width:4
# indent-tabs-mode:nil
# End:
# vim: set expandtab tabstop=4 shiftwidth=4: