Make DOM treebuilder's AttrList return a MutableMapping

Author: gsnedders

html5lib/treebuilders/dom.py

@@ -1,6 +1,7 @@
 from __future__ import absolute_import, division, unicode_literals
 
 
+from collections import MutableMapping
 from xml.dom import minidom, Node
 import weakref
 
@@ -13,34 +14,41 @@
 def getDomBuilder(DomImplementation):
     Dom = DomImplementation
 
-    class AttrList(object):
+    class AttrList(MutableMapping):
         def __init__(self, element):
             self.element = element
 
         def __iter__(self):
-            return list(self.element.attributes.items()).__iter__()
+            return iter(self.element.attributes.keys())
 
         def __setitem__(self, name, value):
-            self.element.setAttribute(name, value)
+            if isinstance(name, tuple):
+                raise NotImplementedError
+            else:
+                attr = self.element.ownerDocument.createAttribute(name)
+                attr.value = value
+                self.element.attributes[name] = attr
 
         def __len__(self):
-            return len(list(self.element.attributes.items()))
+            return len(self.element.attributes)
 
         def items(self):
-            return [(item[0], item[1]) for item in
-                    list(self.element.attributes.items())]
+            return list(self.element.attributes.items())
 
-        def keys(self):
-            return list(self.element.attributes.keys())
+        def values(self):
+            return list(self.element.attributes.values())
 
         def __getitem__(self, name):
-            return self.element.getAttribute(name)
+            if isinstance(name, tuple):
+                raise NotImplementedError
+            else:
+                return self.element.attributes[name].value
 
-        def __contains__(self, name):
+        def __delitem__(self, name):
             if isinstance(name, tuple):
                 raise NotImplementedError
             else:
-                return self.element.hasAttribute(name)
+                del self.element.attributes[name]
 
     class NodeBuilder(_base.Node):
         def __init__(self, element):