fix test_popen when the path to python has spaces #7671
diff --git a/Lib/test/test_popen.py b/Lib/test/test_popen.py
index cb65fdf..454ba17 100644
--- a/Lib/test/test_popen.py
+++ b/Lib/test/test_popen.py
@@ -14,12 +14,10 @@
 # This results in Python being spawned and printing the sys.argv list.
 # We can then eval() the result of this, and see what each argv was.
 python = sys.executable
-if ' ' in python:
-    python = '"' + python + '"'     # quote embedded space for cmdline
 
 class PopenTest(unittest.TestCase):
     def _do_test_commandline(self, cmdline, expected):
-        cmd = '%s -c "import sys;print sys.argv" %s' % (python, cmdline)
+        cmd = '%r -c "import sys;print sys.argv" %s' % (python, cmdline)
         data = os.popen(cmd).read()
         got = eval(data)[1:] # strip off argv[0]
         self.assertEqual(got, expected)