Fix SF bug #667147, Segmentation fault printing str subclass
Fix infinite recursion which occurred when printing an object
whose __str__() returned self.
Will backport
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 023fcc8..da4bd03 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -1,6 +1,6 @@
# Test enhancements related to descriptors and new-style classes
-from test.test_support import verify, vereq, verbose, TestFailed, TESTFN
+from test.test_support import verify, vereq, verbose, TestFailed, TESTFN, get_original_stdout
from copy import deepcopy
import warnings
@@ -1821,6 +1821,29 @@
unsafecmp(1, 1L)
unsafecmp(1L, 1)
+ class Letter(str):
+ def __new__(cls, letter):
+ if letter == 'EPS':
+ return str.__new__(cls)
+ return str.__new__(cls, letter)
+ def __str__(self):
+ if not self:
+ return 'EPS'
+ return self
+
+ # sys.stdout needs to be the original to trigger the recursion bug
+ import sys
+ test_stdout = sys.stdout
+ sys.stdout = get_original_stdout()
+ try:
+ # nothing should actually be printed, this should raise an exception
+ print Letter('w')
+ except RuntimeError:
+ pass
+ else:
+ raise TestFailed, "expected a RuntimeError for print recursion"
+ sys.stdout = test_stdout
+
def weakrefs():
if verbose: print "Testing weak references..."
import weakref