Fixed #37023 -- Made XML serializer put each ManyToManyField object on its own line.

Author: timgraham

django/core/serializers/xml_serializer.py

@@ -199,6 +199,8 @@ def queryset_iterator(obj, field):
             else:
 
                 def handle_m2m(value):
+                    # Put each object on its own line.
+                    self.indent(self.indent_level + 1)
                     self.xml.addQuickElement("object", attrs={"pk": str(value.pk)})
 
                 def queryset_iterator(obj, field):
@@ -217,9 +219,13 @@ def queryset_iterator(obj, field):
                 field.name,
                 queryset_iterator(obj, field),
             )
+            relobj = None
             for relobj in m2m_iter:
                 handle_m2m(relobj)
-
+            if relobj:
+                # If there are related objects (which appear each on their own
+                # line), put the closing </field> on the next line.
+                self.indent(self.indent_level)
             self.xml.endElement("field")
             self.indent_level -= 1
 

tests/serializers/test_xml.py

@@ -24,7 +24,10 @@ class XmlSerializerTestCase(SerializersTestBase, TestCase):
     <field name="author" rel="ManyToOneRel" to="serializers.author">%(author_pk)s</field>
     <field name="headline" type="CharField">Poker has no place on ESPN</field>
     <field name="pub_date" type="DateTimeField">2006-06-16T11:00:00</field>
-    <field name="categories" rel="ManyToManyRel" to="serializers.category"><object pk="%(first_category_pk)s"></object><object pk="%(second_category_pk)s"></object></field>
+    <field name="categories" rel="ManyToManyRel" to="serializers.category">
+      <object pk="%(first_category_pk)s"></object>
+      <object pk="%(second_category_pk)s"></object>
+    </field>
     <field name="meta_data" rel="ManyToManyRel" to="serializers.categorymetadata"></field>
     <field name="topics" rel="ManyToManyRel" to="serializers.topic"></field>
   </object>