trying out isolating env variables

3 files changed, 17 insertions, 2 deletions

diff --git a/tox/__init__.py b/tox/__init__.py
index c206441..95f2dfb 100644
--- a/tox/__init__.py
+++ b/tox/__init__.py
@@ -1,5 +1,5 @@
 #
-__version__ = '1.9.3.dev1'
+__version__ = '2.0.0.dev1'
 
 class exception:
     class Error(Exception):
diff --git a/tox/_config.py b/tox/_config.py
index b9ffc62..2fae46a 100644
--- a/tox/_config.py
+++ b/tox/_config.py
@@ -1,6 +1,7 @@
 import argparse
 import os
 import random
+from fnmatch import fnmatchcase
 import sys
 import re
 import shlex
@@ -366,6 +367,17 @@ class parseini:
         if config.hashseed is not None:
             setenv['PYTHONHASHSEED'] = config.hashseed
         setenv.update(reader.getdict(section, 'setenv'))
+
+        # read passenv
+        vc.passenv = set(["PATH"])
+        if sys.platform == "win32":
+            vc.passenv.add("SYSTEMROOT")  # needed for python's crypto module
+            vc.passenv.add("PATHEXT")     # needed for discovering executables
+        for spec in reader.getlist(section, "passenv", sep=" "):
+            for name in os.environ:
+                if fnmatchcase(name, spec):
+                    vc.passenv.add(name)
+
         vc.setenv = setenv
         if not vc.setenv:
             vc.setenv = None
diff --git a/tox/_venv.py b/tox/_venv.py
index eff932d..8666785 100644
--- a/tox/_venv.py
+++ b/tox/_venv.py
@@ -326,7 +326,10 @@ class VirtualEnv(object):
                                      action=action, extraenv=extraenv)
 
     def _getenv(self, extraenv={}):
-        env = os.environ.copy()
+        env = {}
+        for envname in self.envconfig.passenv:
+            if envname in os.environ:
+                env[envname] = os.environ[envname]
         setenv = self.envconfig.setenv
         if setenv:
             env.update(setenv)