Adjust sorting from cmp= to key= syntax

src/mio/parser.py

@@ -136,58 +136,6 @@ def xml_escape(s):
         
     return result
 
-class AttrSortWrapper:
-    """Wrapper class for sorting attributes
-
-    [see Node._xml(...)]"""
-    def __init__(self, node, sort):
-        self.node = node
-        self.sort = sort
-
-    def __call__(self, a, b):
-        """
-        Return the sort order between attributes 'a' and 'b'.
-
-        If sort returns None, a standard Python comparison is used.
-        """
-        result = None
-        if self.sort:
-            result = self.sort(self.node, a, b)
-        if result == None:
-            if a < b:
-                result = -1
-            elif a > b:
-                result = 1
-            else:
-                result = 0
-        return result
-    
-class TagSortWrapper:
-    """Wrapper class for sorting tags
-    
-    [see Node._xml(...)]"""
-    def __init__(self, parent, sort):
-        self.parent = parent
-        self.sort = sort
-
-    def __call__(self, a, b):
-        """
-        Return the sort order between tags 'a' and 'b'.
-
-        If sort returns None, a standard Python comparison is used.
-        """
-        result = None
-        if self.sort:
-            result = self.sort(self.parent, a, b)
-        if result == None:
-            if a._tag < b._tag:
-                result = -1
-            elif a._tag > b._tag:
-                result = 1
-            else:
-                result = 0
-        return result
-    
 class ChildAccessor:
     """Helper class for iterating over xml trees
     
@@ -374,14 +322,13 @@ class Node:
         else:
             return AttributeAccessor(self, attr)
     
-    def _xml(self, indent=0, attr_sort=None, tag_sort=None, width=80):
+    def _xml(self, indent=0, attr_key=None, node_key=None, width=80):
         """Generate a prettyprinted xml of the tree rooted in this node"""
         result = ""
         line = "%s<%s" % ("  " * indent, self._tag)
         blanks = " " * len(line)
         for k in sorted(self._attribute.keys(),
-                        key=(attr_sort and AttrSortWrapper(self, attr_sort)
-                             or None)):
+                        key=attr_key and (lambda a: attr_key(self, a))):
             s = " %s='%s'" % (k, xml_escape(self._attribute[k]))
             if len(line) + len(s) > width:
                 result += "%s\n" % line
@@ -396,12 +343,9 @@ class Node:
                 result += '\n'.join(self._char)
                 result += '\n'
                 pass
-            print("YYY", (tag_sort and TagSortWrapper(self, tag_sort)
-                          or None), "\n")
             for c in sorted(self._children,
-                            key=(tag_sort and TagSortWrapper(self, tag_sort)
-                                 or None)):
-                result += c._xml(indent + 1, attr_sort, tag_sort, width)
+                            key=node_key and (lambda c: node_key(self, c))):
+                result += c._xml(indent + 1, attr_key, node_key, width)
             result += "%s</%s>\n" % ("  " * indent, self._tag)
         return result
 
@@ -453,6 +397,9 @@ class Comment:
         self._tag = ''
         self._attribute = { '': content}
 
+    def __lt__(self, other):
+        return self._tag < other._tag
+
     def __copy__(self):
         """Copy self"""
         result = Comment(self._content, self._line)
@@ -462,7 +409,7 @@ class Comment:
         """Copy node and all children"""
         return self.__copy__()
     
-    def _xml(self, indent=0, attr_sort=None, tag_sort=None, width=80):
+    def _xml(self, indent=0, attr_key=None, node_key=None, width=80):
         """Generate a prettyprinted xml of the tree rooted in this node"""
         result = "%s<!--" % ("  " * indent)
         result += self._attribute['']