Forward-port of r52136,52138: a review of overflow-detecting code.
* unified the way intobject, longobject and mystrtoul handle
values around -sys.maxint-1.
* in general, trying to entierely avoid overflows in any computation
involving signed ints or longs is extremely involved. Fixed a few
simple cases where a compiler might be too clever (but that's all
guesswork).
* more overflow checks against bad data in marshal.c.
* 2.5 specific: fixed a number of places that were still confusing int
and Py_ssize_t. Some of them could potentially have caused
"real-world" breakage.
* list.pop(x): fixing overflow issues on x was messy. I just reverted
to PyArg_ParseTuple("n"), which does the right thing. (An obscure
test was trying to give a Decimal to list.pop()... doesn't make
sense any more IMHO)
* trying to write a few tests...
diff --git a/Lib/test/test_long.py b/Lib/test/test_long.py
index 7b0c7b0..ae132ad 100644
--- a/Lib/test/test_long.py
+++ b/Lib/test/test_long.py
@@ -247,17 +247,23 @@
"long(-sys.maxint-1) != -sys.maxint-1")
# long -> int should not fail for hugepos_aslong or hugeneg_aslong
+ x = int(hugepos_aslong)
try:
- self.assertEqual(int(hugepos_aslong), hugepos,
+ self.assertEqual(x, hugepos,
"converting sys.maxint to long and back to int fails")
except OverflowError:
self.fail("int(long(sys.maxint)) overflowed!")
+ if not isinstance(x, int):
+ raise TestFailed("int(long(sys.maxint)) should have returned int")
+ x = int(hugeneg_aslong)
try:
- self.assertEqual(int(hugeneg_aslong), hugeneg,
+ self.assertEqual(x, hugeneg,
"converting -sys.maxint-1 to long and back to int fails")
except OverflowError:
self.fail("int(long(-sys.maxint-1)) overflowed!")
-
+ if not isinstance(x, int):
+ raise TestFailed("int(long(-sys.maxint-1)) should have "
+ "returned int")
# but long -> int should overflow for hugepos+1 and hugeneg-1
x = hugepos_aslong + 1
try:
@@ -282,6 +288,17 @@
self.assert_(type(y) is long,
"overflowing int conversion must return long not long subtype")
+ # long -> Py_ssize_t conversion
+ class X(object):
+ def __getslice__(self, i, j):
+ return i, j
+
+ self.assertEqual(X()[-5L:7L], (-5, 7))
+ # use the clamping effect to test the smallest and largest longs
+ # that fit a Py_ssize_t
+ slicemin, slicemax = X()[-2L**100:2L**100]
+ self.assertEqual(X()[slicemin:slicemax], (slicemin, slicemax))
+
# ----------------------------------- tests of auto int->long conversion
def test_auto_overflow(self):