The endless 460020 bug.
Disable t[:], t*0, t*1 optimizations when t is of a tuple subclass type.
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 7095f0b..5c4db30 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -1417,9 +1417,18 @@
a = madtuple((1,2,3,4,5))
verify(tuple(a) == (1,2,3,4,5))
verify(tuple(a).__class__ is tuple)
+ verify(a[:].__class__ is tuple)
+ verify((a * 1).__class__ is tuple)
+ verify((a * 0).__class__ is tuple)
+ verify((a + ()).__class__ is tuple)
a = madtuple(())
verify(tuple(a) == ())
verify(tuple(a).__class__ is tuple)
+ verify((a + a).__class__ is tuple)
+ verify((a * 0).__class__ is tuple)
+ verify((a * 1).__class__ is tuple)
+ verify((a * 2).__class__ is tuple)
+ verify(a[:].__class__ is tuple)
class madstring(str):
_rev = None
diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index b07eb74..f371e1e 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -298,8 +298,7 @@
ihigh = a->ob_size;
if (ihigh < ilow)
ihigh = ilow;
- if (ilow == 0 && ihigh == a->ob_size) {
- /* XXX can only do this if tuples are immutable! */
+ if (ilow == 0 && ihigh == a->ob_size && PyTuple_CheckExact(a)) {
Py_INCREF(a);
return (PyObject *)a;
}
@@ -366,10 +365,14 @@
if (n < 0)
n = 0;
if (a->ob_size == 0 || n == 1) {
- /* Since tuples are immutable, we can return a shared
- copy in this case */
- Py_INCREF(a);
- return (PyObject *)a;
+ if (PyTuple_CheckExact(a)) {
+ /* Since tuples are immutable, we can return a shared
+ copy in this case */
+ Py_INCREF(a);
+ return (PyObject *)a;
+ }
+ if (a->ob_size == 0)
+ return PyTuple_New(0);
}
size = a->ob_size * n;
if (size/a->ob_size != n)