From ee1ae7ccb76b9ae81ae2c4e9c04ce71d7b605038 Mon Sep 17 00:00:00 2001 From: Benjamin Peterson Date: Sun, 8 Feb 2009 21:07:20 +0000 Subject: [PATCH] fix len() when __len__() returns a non number type #5137 --- Lib/test/test_builtin.py | 12 ++++++++++++ Misc/NEWS | 3 +++ Objects/typeobject.c | 2 +- 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py index 0aa0d527a2..a62e1244c2 100644 --- a/Lib/test/test_builtin.py +++ b/Lib/test/test_builtin.py @@ -611,6 +611,18 @@ class BuiltinTest(unittest.TestCase): def __len__(self): raise ValueError self.assertRaises(ValueError, len, BadSeq()) + class InvalidLen: + def __len__(self): + return None + self.assertRaises(TypeError, len, InvalidLen()) + class FloatLen: + def __len__(self): + return 4.5 + self.assertRaises(TypeError, len, FloatLen()) + class HugeLen: + def __len__(self): + return sys.maxsize + 1 + self.assertRaises(OverflowError, len, HugeLen()) def test_map(self): self.assertEqual( diff --git a/Misc/NEWS b/Misc/NEWS index a0a8d1fab7..5a3b4adad1 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -12,6 +12,9 @@ What's New in Python 3.1 alpha 0 Core and Builtins ----------------- +- Issue #5137: Make len() correctly raise a TypeError when a __len__ method + returns a non-number type. + - Issue #5182: Removed memoryview.__str__. - Issue #1717: Removed builtin cmp() function, dropped tp_compare diff --git a/Objects/typeobject.c b/Objects/typeobject.c index 47e425cab1..a362b8457d 100644 --- a/Objects/typeobject.c +++ b/Objects/typeobject.c @@ -4618,7 +4618,7 @@ slot_sq_length(PyObject *self) if (res == NULL) return -1; - len = PyLong_AsSsize_t(res); + len = PyNumber_AsSsize_t(res, PyExc_OverflowError); Py_DECREF(res); if (len < 0) { if (!PyErr_Occurred()) -- 2.40.0