pythoncapi
diff --git a/‎Misc/NEWS.d/next/C API/2018-06-21-17-19-31.bpo-32500.WGCNad.rst‎
Lines changed: 4 additions & 0 deletions b/‎Misc/NEWS.d/next/C API/2018-06-21-17-19-31.bpo-32500.WGCNad.rst‎
Lines changed: 4 additions & 0 deletions
diff --git a/‎Objects/abstract.c‎
Lines changed: 20 additions & 0 deletions b/‎Objects/abstract.c‎
Lines changed: 20 additions & 0 deletions
@@ -0,0 +1,4 @@
+Fixed error messages for :c:func:`PySequence_Size`,
+:c:func:`PySequence_GetItem`, :c:func:`PySequence_SetItem` and
+:c:func:`PySequence_DelItem` called with a mapping and
+:c:func:`PyMapping_Size` called with a sequence.
@@ -1531,6 +1531,10 @@ PySequence_Size(PyObject *s)
         return len;
     }
 
+    if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_length) {
+        type_error("%.200s is not a sequence", s);
+        return -1;
+    }
     type_error("object of type '%.200s' has no len()", s);
     return -1;
 }
@@ -1677,6 +1681,9 @@ PySequence_GetItem(PyObject *s, Py_ssize_t i)
         return m->sq_item(s, i);
     }
 
+    if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_subscript) {
+        return type_error("%.200s is not a sequence", s);
+    }
     return type_error("'%.200s' object does not support indexing", s);
 }
 
@@ -1728,6 +1735,10 @@ PySequence_SetItem(PyObject *s, Py_ssize_t i, PyObject *o)
         return m->sq_ass_item(s, i, o);
     }
 
+    if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_ass_subscript) {
+        type_error("%.200s is not a sequence", s);
+        return -1;
+    }
     type_error("'%.200s' object does not support item assignment", s);
     return -1;
 }
@@ -1757,6 +1768,10 @@ PySequence_DelItem(PyObject *s, Py_ssize_t i)
         return m->sq_ass_item(s, i, (PyObject *)NULL);
     }
 
+    if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_ass_subscript) {
+        type_error("%.200s is not a sequence", s);
+        return -1;
+    }
     type_error("'%.200s' object doesn't support item deletion", s);
     return -1;
 }
@@ -2093,6 +2108,11 @@ PyMapping_Size(PyObject *o)
         return len;
     }
 
+    if (o->ob_type->tp_as_sequence && o->ob_type->tp_as_sequence->sq_length) {
+        type_error("%.200s is not a mapping", o);
+        return -1;
+    }
+    /* PyMapping_Size() can be called from PyObject_Size(). */
     type_error("object of type '%.200s' has no len()", o);
     return -1;
 }
Original file line number	Diff line number	Diff line change
`@@ -1531,6 +1531,10 @@ PySequence_Size(PyObject *s)`
`1531`	`1531`	`return len;`
`1532`	`1532`	`}`
`1533`	`1533`
	`1534`	`+ if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_length) {`
	`1535`	`+ type_error("%.200s is not a sequence", s);`
	`1536`	`+ return -1;`
	`1537`	`+ }`
`1534`	`1538`	`type_error("object of type '%.200s' has no len()", s);`
`1535`	`1539`	`return -1;`
`1536`	`1540`	`}`
`@@ -1677,6 +1681,9 @@ PySequence_GetItem(PyObject *s, Py_ssize_t i)`
`1677`	`1681`	`return m->sq_item(s, i);`
`1678`	`1682`	`}`
`1679`	`1683`
	`1684`	`+ if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_subscript) {`
	`1685`	`+ return type_error("%.200s is not a sequence", s);`
	`1686`	`+ }`
`1680`	`1687`	`return type_error("'%.200s' object does not support indexing", s);`
`1681`	`1688`	`}`
`1682`	`1689`
`@@ -1728,6 +1735,10 @@ PySequence_SetItem(PyObject s, Py_ssize_t i, PyObject o)`
`1728`	`1735`	`return m->sq_ass_item(s, i, o);`
`1729`	`1736`	`}`
`1730`	`1737`
	`1738`	`+ if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_ass_subscript) {`
	`1739`	`+ type_error("%.200s is not a sequence", s);`
	`1740`	`+ return -1;`
	`1741`	`+ }`
`1731`	`1742`	`type_error("'%.200s' object does not support item assignment", s);`
`1732`	`1743`	`return -1;`
`1733`	`1744`	`}`
`@@ -1757,6 +1768,10 @@ PySequence_DelItem(PyObject *s, Py_ssize_t i)`
`1757`	`1768`	`return m->sq_ass_item(s, i, (PyObject *)NULL);`
`1758`	`1769`	`}`
`1759`	`1770`
	`1771`	`+ if (s->ob_type->tp_as_mapping && s->ob_type->tp_as_mapping->mp_ass_subscript) {`
	`1772`	`+ type_error("%.200s is not a sequence", s);`
	`1773`	`+ return -1;`
	`1774`	`+ }`
`1760`	`1775`	`type_error("'%.200s' object doesn't support item deletion", s);`
`1761`	`1776`	`return -1;`
`1762`	`1777`	`}`
`@@ -2093,6 +2108,11 @@ PyMapping_Size(PyObject *o)`
`2093`	`2108`	`return len;`
`2094`	`2109`	`}`
`2095`	`2110`
	`2111`	`+ if (o->ob_type->tp_as_sequence && o->ob_type->tp_as_sequence->sq_length) {`
	`2112`	`+ type_error("%.200s is not a mapping", o);`
	`2113`	`+ return -1;`
	`2114`	`+ }`
	`2115`	`+ /* PyMapping_Size() can be called from PyObject_Size(). */`
`2096`	`2116`	`type_error("object of type '%.200s' has no len()", o);`
`2097`	`2117`	`return -1;`
`2098`	`2118`	`}`