Merge remote-tracking branch 'upstream/master' into features

_pytest/runner.py

@@ -7,6 +7,7 @@ import sys
 from time import time
 
 import py
+from _pytest.compat import _PY2
 from _pytest._code.code import TerminalRepr, ExceptionInfo
 from _pytest.outcomes import skip, Skipped, TEST_OUTCOME
 
@@ -134,7 +135,11 @@ def _update_current_test_var(item, when):
     """
     var_name = 'PYTEST_CURRENT_TEST'
     if when:
-        os.environ[var_name] = '{0} ({1})'.format(item.nodeid, when)
+        value = '{0} ({1})'.format(item.nodeid, when)
+        if _PY2:
+            # python 2 doesn't like null bytes on environment variables (see #2644)
+            value = value.replace('\x00', '(null)')
+        os.environ[var_name] = value
     else:
         os.environ.pop(var_name)