From 90e27d38f5ec7c435d32e1eebe0b7a3ad6b60216 Mon Sep 17 00:00:00 2001
From: Georg Brandl <georg@python.org>
Date: Sat, 10 Jun 2006 06:40:50 +0000
Subject: Apply perky's fix for #1503157: "/".join([u"", u""]) raising
 OverflowError. Also improve error message on overflow.

---
 Lib/test/string_tests.py | 2 ++
 Objects/stringobject.c   | 2 +-
 Objects/unicodeobject.c  | 6 +++---
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/Lib/test/string_tests.py b/Lib/test/string_tests.py
index 5a1cc8a..236c529 100644
--- a/Lib/test/string_tests.py
+++ b/Lib/test/string_tests.py
@@ -938,6 +938,8 @@ class MixinStrUnicodeUserStringTest:
         # test.test_string.StringTest.test_join)
         self.checkequal('a b c d', ' ', 'join', ['a', 'b', 'c', 'd'])
         self.checkequal('abcd', '', 'join', ('a', 'b', 'c', 'd'))
+        self.checkequal('bd', '', 'join', ('', 'b', '', 'd'))
+        self.checkequal('ac', '', 'join', ('a', '', 'c', ''))
         self.checkequal('w x y z', ' ', 'join', Sequence())
         self.checkequal('abc', 'a', 'join', ('abc',))
         self.checkequal('z', 'a', 'join', UserList(['z']))
diff --git a/Objects/stringobject.c b/Objects/stringobject.c
index 831d54a..a5c8cc2 100644
--- a/Objects/stringobject.c
+++ b/Objects/stringobject.c
@@ -1788,7 +1788,7 @@ string_join(PyStringObject *self, PyObject *orig)
 			sz += seplen;
 		if (sz < old_sz || sz > PY_SSIZE_T_MAX) {
 			PyErr_SetString(PyExc_OverflowError,
-				"join() is too long for a Python string");
+				"join() result is too long for a Python string");
 			Py_DECREF(seq);
 			return NULL;
 		}
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index bf2425c..064caeb 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -4491,11 +4491,11 @@ PyUnicode_Join(PyObject *separator, PyObject *seq)
         /* Make sure we have enough space for the separator and the item. */
 	itemlen = PyUnicode_GET_SIZE(item);
 	new_res_used = res_used + itemlen;
-	if (new_res_used <= 0)
+	if (new_res_used < 0)
 	    goto Overflow;
 	if (i < seqlen - 1) {
 	    new_res_used += seplen;
-	    if (new_res_used <= 0)
+	    if (new_res_used < 0)
 		goto Overflow;
 	}
 	if (new_res_used > res_alloc) {
@@ -4536,7 +4536,7 @@ PyUnicode_Join(PyObject *separator, PyObject *seq)
 
  Overflow:
     PyErr_SetString(PyExc_OverflowError,
-                    "join() is too long for a Python string");
+                    "join() result is too long for a Python string");
     Py_DECREF(item);
     /* fall through */
 
-- 
cgit v0.12

