# HG changeset patch
# Parent 2ffaac4c8e531de022390e120d5ab35108ed7697
Issue 19176: Inheriting doctype() method is not deprecated usage

diff -r 2ffaac4c8e53 Lib/test/test_xml_etree.py
--- a/Lib/test/test_xml_etree.py	Tue Dec 16 19:43:46 2014 +0200
+++ b/Lib/test/test_xml_etree.py	Tue Mar 31 06:06:25 2015 +0000
@@ -12,6 +12,7 @@
 import sys
 import types
 import unittest
+import warnings
 import weakref
 
 from itertools import product
@@ -2132,6 +2133,16 @@
             ('html', '-//W3C//DTD XHTML 1.0 Transitional//EN',
              'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'))
 
+    def test_inherited_doctype(self):
+        '''Ensure that ordinary usage is not deprecated (Issue 19176)'''
+        with warnings.catch_warnings():
+            warnings.simplefilter('error', DeprecationWarning)
+            class MyParserWithoutDoctype(ET.XMLParser):
+                pass
+            parser = MyParserWithoutDoctype()
+            parser.feed(self.sample2)
+            parser.close()
+
     def test_parse_string(self):
         parser = ET.XMLParser(target=ET.TreeBuilder())
         parser.feed(self.sample3)
diff -r 2ffaac4c8e53 Modules/_elementtree.c
--- a/Modules/_elementtree.c	Tue Dec 16 19:43:46 2014 +0200
+++ b/Modules/_elementtree.c	Tue Mar 31 06:06:25 2015 +0000
@@ -2741,7 +2741,7 @@
 
 } XMLParserObject;
 
-#define XMLParser_CheckExact(op) (Py_TYPE(op) == &XMLParser_Type)
+static PyObject* xmlparser_doctype(XMLParserObject* self, PyObject* args);
 
 /* helpers */
 
@@ -3142,12 +3142,15 @@
     }
 
     /* Now see if the parser itself has a doctype method. If yes and it's
-     * a subclass, call it but warn about deprecation. If it's not a subclass
-     * (i.e. vanilla XMLParser), do nothing.
+     * a custom method, call it but warn about deprecation. If it's only
+     * the vanilla XMLParser method, do nothing.
      */
     parser_doctype = PyObject_GetAttrString(self_pyobj, "doctype");
     if (parser_doctype) {
-        if (!XMLParser_CheckExact(self_pyobj)) {
+        if (!(PyCFunction_Check(parser_doctype) &&
+                PyCFunction_GET_SELF(parser_doctype) == self_pyobj &&
+                PyCFunction_GET_FUNCTION(parser_doctype) ==
+                    (PyCFunction) xmlparser_doctype)) {
             if (PyErr_WarnEx(PyExc_DeprecationWarning,
                             "This method of XMLParser is deprecated.  Define"
                             " doctype() method on the TreeBuilder target.",