Fixed console encoding issue

The issue occured with python 3.3 on windows with dependencies needing to be
compiled (e.g. markupsafe)

2 files changed, 7 insertions, 6 deletions

diff --git a/tests/test_venv.py b/tests/test_venv.py
index 6482e09..f6a2f32 100644
--- a/tests/test_venv.py
+++ b/tests/test_venv.py
@@ -552,8 +552,6 @@ def test_run_install_command(newmocksession):
     assert 'install' in l[0].args
     env = l[0].env
     assert env is not None
-    assert 'PYTHONIOENCODING' in env
-    assert env['PYTHONIOENCODING'] == 'utf_8'
 
 def test_run_custom_install_command(newmocksession):
     mocksession = newmocksession([], """
diff --git a/tox/_venv.py b/tox/_venv.py
index 7e9f45f..d5df526 100644
--- a/tox/_venv.py
+++ b/tox/_venv.py
@@ -1,5 +1,6 @@
 from __future__ import with_statement
 import sys, os
+import codecs
 import py
 import tox
 from tox._config import DepConfig
@@ -276,11 +277,13 @@ class VirtualEnv(object):
                 del os.environ[x]
             except KeyError:
                 pass
-        env = dict(PYTHONIOENCODING='utf_8')
-        if extraenv is not None:
-            env.update(extraenv)
+        old_stdout = sys.stdout
+        sys.stdout = codecs.getwriter('utf8')(sys.stdout)
+        if extraenv is None:
+            extraenv = {}
         self._pcall(argv, cwd=self.envconfig.config.toxinidir,
-                    extraenv=env, action=action)
+                    extraenv=extraenv, action=action)
+        sys.stdout = old_stdout
 
     def _install(self, deps, extraopts=None, action=None):
         if not deps: