Source Code for Module SCons.Platform.virtualenv

  1  """SCons.Platform.virtualenv 
  2   
  3  Support for virtualenv. 
  4  """ 
  5   
  6  # 
  7  # Copyright (c) 2001 - 2019 The SCons Foundation 
  8  # 
  9  # Permission is hereby granted, free of charge, to any person obtaining 
 10  # a copy of this software and associated documentation files (the 
 11  # "Software"), to deal in the Software without restriction, including 
 12  # without limitation the rights to use, copy, modify, merge, publish, 
 13  # distribute, sublicense, and/or sell copies of the Software, and to 
 14  # permit persons to whom the Software is furnished to do so, subject to 
 15  # the following conditions: 
 16  # 
 17  # The above copyright notice and this permission notice shall be included 
 18  # in all copies or substantial portions of the Software. 
 19  # 
 20  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY 
 21  # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE 
 22  # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 23  # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 
 24  # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 
 25  # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
 26  # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 
 27  # 
 28   
 29  __revision__ = "src/engine/SCons/Platform/virtualenv.py 3a41ed6b288cee8d085373ad7fa02894e1903864 2019-01-23 17:30:35 bdeegan" 
 30   
 31  import os 
 32  import sys 
 33  import SCons.Util 
 34   
 35   
 36  virtualenv_enabled_by_default = False 
 37   
 38   
 39 -def _enable_virtualenv_default(): 
 40      return SCons.Util.get_os_env_bool('SCONS_ENABLE_VIRTUALENV', virtualenv_enabled_by_default) 
 41   
 42   
 43 -def _ignore_virtualenv_default(): 
 44      return SCons.Util.get_os_env_bool('SCONS_IGNORE_VIRTUALENV', False) 
 45   
 46   
 47  enable_virtualenv = _enable_virtualenv_default() 
 48  ignore_virtualenv = _ignore_virtualenv_default() 
 49  virtualenv_variables = ['VIRTUAL_ENV', 'PIPENV_ACTIVE'] 
 50   
 51   
 52 -def _running_in_virtualenv(): 
 53      """Returns True, if scons is executed within a virtualenv""" 
 54      # see https://stackoverflow.com/a/42580137 
 55      return (hasattr(sys, 'real_prefix') or 
 56              (hasattr(sys, 'base_prefix') and sys.base_prefix != sys.prefix)) 
 57   
 58   
 59 -def _is_path_in(path, base): 
 60      """Returns true, if **path** is located under the **base** directory.""" 
 61      if not path or not base: # empty path may happen, base too 
 62          return False 
 63      rp = os.path.relpath(path, base) 
 64      return ((not rp.startswith(os.path.pardir)) and (not rp == os.path.curdir)) 
 65   
 66   
 67 -def _inject_venv_variables(env): 
 68      if 'ENV' not in env: 
 69          env['ENV'] = {} 
 70      ENV = env['ENV'] 
 71      for name in virtualenv_variables: 
 72          try: 
 73              ENV[name] = os.environ[name] 
 74          except KeyError: 
 75              pass 
 76   
 77 -def _inject_venv_path(env, path_list=None): 
 78      """Modify environment such that SCons will take into account its virtualenv 
 79      when running external tools.""" 
 80      if path_list is None: 
 81          path_list = os.getenv('PATH') 
 82      env.PrependENVPath('PATH', select_paths_in_venv(path_list)) 
 83   
 84   
 85 -def select_paths_in_venv(path_list): 
 86      """Returns a list of paths from **path_list** which are under virtualenv's 
 87      home directory.""" 
 88      if SCons.Util.is_String(path_list): 
 89          path_list = path_list.split(os.path.pathsep) 
 90      # Find in path_list the paths under the virtualenv's home 
 91      return [path for path in path_list if IsInVirtualenv(path)] 
 92   
 93   
 94 -def ImportVirtualenv(env): 
 95      """Copies virtualenv-related environment variables from OS environment 
 96      to ``env['ENV']`` and prepends virtualenv's PATH to ``env['ENV']['PATH']``. 
 97      """ 
 98      _inject_venv_variables(env) 
 99      _inject_venv_path(env) 
100   
101   
102 -def Virtualenv(): 
103      """Returns path to the virtualenv home if scons is executing within a 
104      virtualenv or None, if not.""" 
105      if _running_in_virtualenv(): 
106          return sys.prefix 
107      return None 
108   
109   
110 -def IsInVirtualenv(path): 
111      """Returns True, if **path** is under virtualenv's home directory. If not, 
112      or if we don't use virtualenv, returns False.""" 
113      return _is_path_in(path, Virtualenv()) 
114   
115   
116  # Local Variables: 
117  # tab-width:4 
118  # indent-tabs-mode:nil 
119  # End: 
120  # vim: set expandtab tabstop=4 shiftwidth=4: 
121