[Python-checkins] CVS: python/dist/src/Lib/test test_mutants.py,1.3,1.4

[Tim Peters]

Update of /cvsroot/python/python/dist/src/Lib/test
In directory usw-pr-cvs1:/tmp/cvs-serv27849/python/dist/src/Lib/test

Modified Files:
	test_mutants.py 
Log Message:
Coredumpers from Michael Hudson, mutating dicts while printing or
converting to string.
Critical bugfix candidate -- if you take this seriously <wink>.


Index: test_mutants.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/test/test_mutants.py,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -r1.3 -r1.4
*** test_mutants.py	2001/05/10 20:18:30	1.3
--- test_mutants.py	2001/06/02 08:02:56	1.4
***************
*** 1,4 ****
! from test_support import verbose
  import random
  
  # From SF bug #422121:  Insecurities in dict comparison.
--- 1,5 ----
! from test_support import verbose, TESTFN
  import random
+ import os
  
  # From SF bug #422121:  Insecurities in dict comparison.
***************
*** 152,153 ****
--- 153,217 ----
  # See last comment block for clues about good values for n.
  test(100)
+ 
+ ##########################################################################
+ # Another segfault bug, distilled by Micheal Hundson from a c.l.py post.
+ 
+ class Child:
+     def __init__(self, parent):
+         self.__dict__['parent'] = parent
+     def __getattr__(self, attr):
+         self.parent.a = 1
+         self.parent.b = 1
+         self.parent.c = 1
+         self.parent.d = 1
+         self.parent.e = 1
+         self.parent.f = 1
+         self.parent.g = 1
+         self.parent.h = 1
+         self.parent.i = 1
+         return getattr(self.parent, attr)
+ 
+ class Parent:
+     def __init__(self):
+         self.a = Child(self)
+ 
+ # Hard to say what this will print!  May vary from time to time.  But
+ # we're specifically trying to test the tp_print slot here, and this is
+ # the clearest way to do it.  We print the result to a temp file so that
+ # the expected-output file doesn't need to change.
+ 
+ f = open(TESTFN, "w")
+ print >> f, Parent().__dict__
+ f.close()
+ os.unlink(TESTFN)
+ 
+ ##########################################################################
+ # And another core-dumper from Michael Hudson.
+ 
+ dict = {}
+ 
+ # Force dict to malloc its table.
+ for i in range(1, 10):
+     dict[i] = i
+ 
+ f = open(TESTFN, "w")
+ 
+ class Machiavelli:
+     def __repr__(self):
+         dict.clear()
+ 
+         # Michael sez:  "doesn't crash without this.  don't know why."
+         # Tim sez:  "luck of the draw; crashes with or without for me."
+         print >> f
+ 
+         return `"machiavelli"`
+ 
+     def __hash__(self):
+         return 0
+ 
+ dict[Machiavelli()] = Machiavelli()
+ 
+ print >> f, str(dict)
+ f.close()
+ os.unlink(TESTFN)
+ del f, dict