bpo-43399: Fix ElementTree.extend not working on iterators (GH-24751)

(cherry picked from commit 51a85dd) Co-authored-by: Alex Prengère <2138730+alexprengere@users.noreply.github.com>
python · miss-islington · Mar 30, 2021 · Mar 30, 2021 · Mar 30, 2021 · 5375551a7b3afa1de09899ff432c61138bab4190
commit 5375551a7b3afa1de09899ff432c61138bab4190
diff --git a/Lib/test/test_xml_etree.py b/Lib/test/test_xml_etree.py
@@ -312,6 +312,9 @@ def test_simpleops(self):
         elem.extend([e])
         self.serialize_check(elem, '<body><tag /><tag2 /></body>')
         elem.remove(e)
+        elem.extend(iter([e]))
+    <
8000
span class='blob-code-inner blob-code-marker ' data-code-marker="+">        self.serialize_check(elem, '<body><tag /><tag2 /></body>')
+        elem.remove(e)
 
         element = ET.Element("tag", key="value")
         self.serialize_check(element, '<tag key="value" />') # 1

diff --git a/Lib/xml/etree/ElementTree.py b/Lib/xml/etree/ElementTree.py
@@ -252,7 +252,7 @@ def extend(self, elements):
         """
         for element in elements:
             self._assert_is_element(element)
-        self._children.extend(elements)
+            self._children.append(element)
 
     def insert(self, index, subelement):
         """Insert *subelement* at position *index*."""

diff --git a/Misc/ACKS b/Misc/ACKS
@@ -1363,6 +1363,7 @@ Matheus Vieira Portela
 Davin Potts
 Guillaume Pratte
 Florian Preinstorfer
+Alex Prengère
 Amrit Prem
 Paul Prescod
 Donovan Preston

diff --git a/Misc/NEWS.d/next/Library/2021-03-04-17-53-46.bpo-43399.Wn95u-.rst b/Misc/NEWS.d/next/Library/2021-03-04-17-53-46.bpo-43399.Wn95u-.rst
@@ -0,0 +1,2 @@
+Fix ``ElementTree.extend`` not working on iterators when using the
+Python implementation
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		Fix ``ElementTree.extend`` not working on iterators when using the
		Python implementation