bytes should be verboten in sum() (fixes #12654)
diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py
index ce1586f..aa9b4e2 100644
--- a/Lib/test/test_builtin.py
+++ b/Lib/test/test_builtin.py
@@ -1128,6 +1128,9 @@
self.assertRaises(TypeError, sum, 42)
self.assertRaises(TypeError, sum, ['a', 'b', 'c'])
self.assertRaises(TypeError, sum, ['a', 'b', 'c'], '')
+ self.assertRaises(TypeError, sum, [b'a', b'c'], b'')
+ values = [bytearray(b'a'), bytearray(b'b')]
+ self.assertRaises(TypeError, sum, values, bytearray(b''))
self.assertRaises(TypeError, sum, [[1], [2], [3]])
self.assertRaises(TypeError, sum, [{2:3}])
self.assertRaises(TypeError, sum, [{2:3}]*2, {2:3})
diff --git a/Misc/NEWS b/Misc/NEWS
index 5cdcb79..0b205ad 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,8 @@
Core and Builtins
-----------------
+- Forbid summing bytes in sum().
+
- Verify the types of AST strings and identifiers provided by the user before
compiling them.
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 291ef45..82fb9ad 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -1888,6 +1888,11 @@
Py_DECREF(iter);
return NULL;
}
+ if (PyBytes_Check(result)) {
+ PyErr_SetString(PyExc_TypeError,
+ "sum() can't sum bytes [use b''.join(seq) instead]");
+ return NULL;
+ }
if (PyByteArray_Check(result)) {
PyErr_SetString(PyExc_TypeError,
"sum() can't sum bytes [use b''.join(seq) instead]");