getoutput wants a string, not a command list

IPython/testing/tools.py

@@ -19,6 +19,7 b' from __future__ import absolute_import'
 #-----------------------------------------------------------------------------
 
 import os
+import pipes
 import re
 import sys
 import tempfile
@@ -187,7 +188,7 b' def ipexec(fname, options=None):'
     _ip = get_ipython()
     test_dir = os.path.dirname(__file__)
 
-    ipython_cmd = [sys.executable, '-m', 'IPython']
+    ipython_cmd = pipes.quote(sys.executable) + " -m IPython"
     # Absolute path for filename
     full_fname = os.path.join(test_dir, fname)
     full_cmd = '%s %s %s' % (ipython_cmd, cmdargs, full_fname)