[Python-3000-checkins] r65341 - in python/branches/py3k: Lib/test/test_exceptions.py Python/errors.c

[amaury.forgeotdarc]

Author: amaury.forgeotdarc
Date: Fri Aug  1 00:56:02 2008
New Revision: 65341

Log:
Correct one of the "MemoryError oddities": 
the traceback would grow each time a MemoryError is raised.


Modified:
   python/branches/py3k/Lib/test/test_exceptions.py
   python/branches/py3k/Python/errors.c

Modified: python/branches/py3k/Lib/test/test_exceptions.py
==============================================================================
--- python/branches/py3k/Lib/test/test_exceptions.py	(original)
+++ python/branches/py3k/Lib/test/test_exceptions.py	Fri Aug  1 00:56:02 2008
@@ -596,6 +596,24 @@
                          "Exception ValueError: ValueError() "
                          "in <class 'KeyError'> ignored\n")
 
+
+    def test_MemoryError(self):
+        # PyErr_NoMemory always raises the same exception instance.
+        # Check that the traceback is not doubled.
+        import traceback
+        def raiseMemError():
+            try:
+                "a" * (sys.maxsize // 2)
+            except MemoryError as e:
+                tb = e.__traceback__
+            else:
+                self.fail("Should have raises a MemoryError")
+            return traceback.format_tb(tb)
+
+        tb1 = raiseMemError()
+        tb2 = raiseMemError()
+        self.assertEqual(tb1, tb2)
+
 def test_main():
     run_unittest(ExceptionTests)
 

Modified: python/branches/py3k/Python/errors.c
==============================================================================
--- python/branches/py3k/Python/errors.c	(original)
+++ python/branches/py3k/Python/errors.c	Fri Aug  1 00:56:02 2008
@@ -321,7 +321,17 @@
 
 	/* raise the pre-allocated instance if it still exists */
 	if (PyExc_MemoryErrorInst)
+	{
+		/* Clear the previous traceback, otherwise it will be appended
+		 * to the current one.
+		 *
+		 * The following statement is not likely to raise any error;
+		 * if it does, we simply discard it.
+		 */
+		PyException_SetTraceback(PyExc_MemoryErrorInst, Py_None);
+
 		PyErr_SetObject(PyExc_MemoryError, PyExc_MemoryErrorInst);
+	}
 	else
 		/* this will probably fail since there's no memory and hee,
 		   hee, we have to instantiate this class