Merged revisions 78835-78837,78870 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r78835 | victor.stinner | 2010-03-11 13:34:39 +0100 (jeu., 11 mars 2010) | 7 lines

  Issue #7774: Set sys.executable to an empty string if argv[0] has been
  set to an non existent program name and Python is unable to retrieve the real
  program name.

  Fix also sysconfig: if sys.executable is an empty string, use the current
  working directory.
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  r78836 | victor.stinner | 2010-03-11 14:27:35 +0100 (jeu., 11 mars 2010) | 4 lines

  Fix test_executable introduce in previous commit (r78835): Windows is able to
  retrieve the absolute Python path even if argv[0] has been set to a non
  existent program name.
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  r78837 | victor.stinner | 2010-03-11 14:46:06 +0100 (jeu., 11 mars 2010) | 3 lines

  Another fix to test_executable() of test_sys: set the current working to avoid
  the #7774 bug.
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  r78870 | victor.stinner | 2010-03-12 15:30:26 +0100 (ven., 12 mars 2010) | 1 line

  NEWS: issue #7774 is related to Library (sys), not Core and Builtins
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diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index 149f473..5c18006 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -395,6 +395,20 @@
         self.assertEqual(sys.call_tracing(str, (2,)), "2")
         self.assertRaises(TypeError, sys.call_tracing, str, 2)
 
+    def test_executable(self):
+        # Issue #7774: Ensure that sys.executable is an empty string if argv[0]
+        # has been set to an non existent program name and Python is unable to
+        # retrieve the real program name
+        import subprocess
+        # For a normal installation, it should work without 'cwd'
+        # argument. For test runs in the build directory, see #7774.
+        python_dir = os.path.dirname(os.path.realpath(sys.executable))
+        p = subprocess.Popen(
+            ["nonexistent", "-c", 'import sys; print repr(sys.executable)'],
+            executable=sys.executable, stdout=subprocess.PIPE, cwd=python_dir)
+        executable = p.communicate()[0].strip()
+        p.wait()
+        self.assert_(executable in ["''", repr(sys.executable)], executable)
 
 class SizeofTest(unittest.TestCase):