Merged revisions 78835-78837,78870 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  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.
........
  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.
........
  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.
........
  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
........

Lib/test/test_sys.py

@@ -395,6 +395,20 @@ class SysModuleTest(unittest.TestCase):
         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):
 

Misc/NEWS

@@ -21,6 +21,10 @@ Core and Builtins
 Library
 -------
 
+- 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
+
 - Issue #1054943: Fix unicodedata.normalize('NFC', text) for the Public Review
   Issue #29
 

Modules/getpath.c

@@ -441,7 +441,7 @@ calculate_path(void)
 	}
 	else
 		progpath[0] = '\0';
-	if (progpath[0] != SEP)
+	if (progpath[0] != SEP && progpath[0] != '\0')
 		absolutize(progpath);
 	strncpy(argv0_path, progpath, MAXPATHLEN);
 	argv0_path[MAXPATHLEN] = '\0';