From 7b07a41e9f078065b966a2414a24c0e5b7889ef7 Mon Sep 17 00:00:00 2001 From: Tim Peters Date: Tue, 11 Sep 2001 19:48:03 +0000 Subject: The endless 460020 bug. Disable t[:], t*0, t*1 optimizations when t is of a tuple subclass type. --- Lib/test/test_descr.py | 9 +++++++++ Objects/tupleobject.c | 15 +++++++++------ 2 files changed, 18 insertions(+), 6 deletions(-) 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 @@ def inherits(): 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 @@ tupleslice(register PyTupleObject *a, register int ilow, register int ihigh) 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 @@ tuplerepeat(PyTupleObject *a, int n) 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) -- cgit v0.12