Add a new bindings2/scripts directory for Dart bindings

sky/engine/bindings2/scripts/idlnode.py

+#!/usr/bin/python
+# Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+import os
+import sys
+
+import idl_definitions
+from idl_types import IdlType, IdlUnionType, IdlArrayOrSequenceType
+
+from compute_interfaces_info_overall import interfaces_info
+
+
+new_asts = {}
+
+
+_operation_suffix_map = {
+  '__getter__': "Getter",
+  '__setter__': "Setter",
+  '__delete__': "Deleter",
+}
+
+class IDLNode(object):
+  """Base class for all IDL elements.
+  IDLNode may contain various child nodes, and have properties. Examples
+  of IDLNode are interfaces, interface members, function arguments,
+  etc.
+  """
+
+  def __init__(self, ast):
+    """Initializes an IDLNode from a PegParser AST output."""
+    self.id = self._find_first(ast, 'Id') if ast is not None else None
+
+
+  def __repr__(self):
+    """Generates string of the form <class id extra extra ... 0x12345678>."""
+    extras = self._extra_repr()
+    if isinstance(extras, list):
+      extras = ' '.join([str(e) for e in extras])
+    try:
+      if self.id:
+        return '<%s %s 0x%x>' % (
+            type(self).__name__,
+            ('%s %s' % (self.id, extras)).strip(),
+            hash(self))
+      return '<%s %s 0x%x>' % (
+          type(self).__name__,
+          extras,
+          hash(self))
+    except Exception, e:
+      return "can't convert to string: %s" % e
+
+  def _extra_repr(self):
+    """Returns string of extra info for __repr__()."""
+    return ''
+
+  def __cmp__(self, other):
+    """Override default compare operation.
+    IDLNodes are equal if all their properties are equal."""
+    if other is None or not isinstance(other, IDLNode):
+      return 1
+    return self.__dict__.__cmp__(other.__dict__)
+
+  def reset_id(self, newId):
+    """Reset the id of the Node.  This is typically done during a normalization
+    phase (e.g., "DOMWindow" -> "Window")."""
+    self.id = newId
+
+  def all(self, type_filter=None):
+    """Returns a list containing this node and all it child nodes
+    (recursive).
+
+    Args:
+      type_filter -- can be used to limit the results to a specific
+        node type (e.g. IDLOperation).
+    """
+    res = []
+    if type_filter is None or isinstance(self, type_filter):
+      res.append(self)
+    for v in self._all_subnodes():
+      if isinstance(v, IDLNode):
+        res.extend(v.all(type_filter))
+      elif isinstance(v, list):
+        for item in v:
+          if isinstance(item, IDLNode):
+            res.extend(item.all(type_filter))
+    return res
+
+  def _all_subnodes(self):
+    """Accessor used by all() to find subnodes."""
+    return self.__dict__.values()
+
+  def to_dict(self):
+    """Converts the IDLNode and its children into a dictionary.
+    This method is useful mostly for debugging and pretty printing.
+    """
+    res = {}
+    for (k, v) in self.__dict__.items():
+      if v == None or v == False or v == [] or v == {}:
+        # Skip empty/false members.
+        continue
+      elif isinstance(v, IDLDictNode) and not len(v):
+        # Skip empty dict sub-nodes.
+        continue
+      elif isinstance(v, list):
+        # Convert lists:
+        new_v = []
+        for sub_node in v:
+          if isinstance(sub_node, IDLNode):
+            # Convert sub-node:
+            new_v.append(sub_node.to_dict())
+          else:
+            new_v.append(sub_node)
+        v = new_v
+      elif isinstance(v, IDLNode):
+        # Convert sub-node:
+        v = v.to_dict()
+      res[k] = v
+    return res
+
+  def _find_all(self, ast, label, max_results=sys.maxint):
+    """Searches the AST for tuples with a given label. The PegParser
+    output is composed of lists and tuples, where the tuple 1st argument
+    is a label. If ast root is a list, will search recursively inside each
+    member in the list.
+
+    Args:
+      ast -- the AST to search.
+      label -- the label to look for.
+      res -- results are put into this list.
+      max_results -- maximum number of results.
+    """
+    res = []
+    if max_results <= 0:
+      return res
+
+    if isinstance(ast, list):
+      for childAst in ast:
+        if childAst and \
+           not(isinstance(childAst, dict)) and \
+           not(isinstance(childAst, str)) and \
+           not(isinstance(childAst, tuple)) and \
+           childAst.__module__ == "idl_definitions":
+          field_name = self._convert_label_to_field(label)
+          if hasattr(childAst, field_name):
+            field_value = getattr(childAst, field_name)
+            # It's an IdlType we need the string name of the type.
+            if field_name == 'idl_type':
+              field_value =  getattr(field_value, 'base_type')
+            res.append(field_value)
+        else:
+          sub_res = self._find_all(childAst, label,
+                       max_results - len(res))
+          res.extend(sub_res)
+    elif isinstance(ast, tuple):
+      (nodeLabel, value) = ast
+      if nodeLabel == label:
+        res.append(value)
+    # TODO(terry): Seems bogus to check for so many things probably better to just
+    #              pass in blink_compile and drive it off from that...
+    elif (ast and not(isinstance(ast, dict)) and
+          not(isinstance(ast, str)) and
+          (ast.__module__ == "idl_definitions" or ast.__module__ == "idl_types")):
+      field_name = self._convert_label_to_field(label)
+      if hasattr(ast, field_name):
+        field_value = getattr(ast, field_name)
+        if field_value:
+          if label == 'Interface' or label == 'Enum':
+            for key in field_value:
+              value = field_value[key]
+              res.append(value)
+          elif isinstance(field_value, list):
+            for item in field_value:
+              res.append(item)
+          elif label == 'ParentInterface' or label == 'InterfaceType':
+            # Fetch the AST for the parent interface.
+            parent_idlnode = new_asts[field_value]
+            res.append(parent_idlnode.interfaces[field_value])
+          else:
+            res.append(field_value)
+
+    return res
+
+  def _find_first(self, ast, label):
+    """Convenience method for _find_all(..., max_results=1).
+    Returns a single element instead of a list, or None if nothing
+    is found."""
+    res = self._find_all(ast, label, max_results=1)
+    if len(res):
+      return res[0]
+    return None
+
+  def _has(self, ast, label):
+    """Returns true if an element with the given label is
+    in the AST by searching for it."""
+    return len(self._find_all(ast, label, max_results=1)) == 1
+
+  # Mapping from original AST tuple names to new AST field names idl_definitions.Idl*.
+  def _convert_label_to_field(self, label):
+    label_field = {
+      # Keys old AST names, Values Blink IdlInterface names.
+      'ParentInterface': 'parent',
+      'Id': 'name',
+      'Interface': 'interfaces',
+      'Callback': 'is_callback',
+      'Partial': 'is_partial',
+      'Operation': 'operations',
+      'Attribute': 'attributes',
+      'Const': 'constants',
+      'Type': 'idl_type',
+      'ExtAttrs':  'extended_attributes',
+      'Special': 'specials',
+      'ReturnType': 'idl_type',
+      'Argument': 'arguments',
+      'InterfaceType': 'name',
+      'ConstExpr': 'value',
+      'Static': 'is_static',
+      'ReadOnly': 'is_read_only',
+      'Optional': 'is_optional',
+      'Nullable': 'is_nullable',
+      'Enum': 'enumerations',
+      'Annotation': '',         # TODO(terry): Ignore annotation used for database cache.
+      'TypeDef': '',            # typedef in an IDL are already resolved.
+    }
+    result = label_field.get(label)
+    if result != '' and not(result):
+      print 'FATAL ERROR: AST mapping name not found %s.' % label
+    return result if result else ''
+
+  def _convert_all(self, ast, label, idlnode_ctor):
+    """Converts AST elements into IDLNode elements.
+    Uses _find_all to find elements with a given label and converts
+    them into IDLNodes with a given constructor.
+    Returns:
+      A list of the converted nodes.
+    Args:
+      ast -- the ast element to start a search at.
+      label -- the element label to look for.
+      idlnode_ctor -- a constructor function of one of the IDLNode
+        sub-classes.
+    """
+    res = []
+    found = self._find_all(ast, label)
+    if not found:
+      return res
+    if not isinstance(found, list):
+      raise RuntimeError("Expected list but %s found" % type(found))
+    for childAst in found:
+      converted = idlnode_ctor(childAst)
+      res.append(converted)
+    return res
+
+  def _convert_first(self, ast, label, idlnode_ctor):
+    """Like _convert_all, but only converts the first found results."""
+    childAst = self._find_first(ast, label)
+    if not childAst:
+      return None
+    return idlnode_ctor(childAst)
+
+  def _convert_ext_attrs(self, ast):
+    """Helper method for uniform conversion of extended attributes."""
+    self.ext_attrs = IDLExtAttrs(ast)
+
+  def _convert_annotations(self, ast):
+    """Helper method for uniform conversion of annotations."""
+    self.annotations = IDLAnnotations(ast)
+
+
+class IDLDictNode(IDLNode):
+  """Base class for dictionary-like IDL nodes such as extended attributes
+  and annotations. The base class implements various dict interfaces."""
+
+  def __init__(self, ast):
+    IDLNode.__init__(self, None)
+    if ast is not None and isinstance(ast, dict):
+      self.__map = ast
+    else:
+      self.__map = {}
+
+  def __len__(self):
+    return len(self.__map)
+
+  def __getitem__(self, key):
+    return self.__map[key]
+
+  def __setitem__(self, key, value):
+    self.__map[key] = value
+
+  def __delitem__(self, key):
+    del self.__map[key]
+
+  def __contains__(self, key):
+    return key in self.__map
+
+  def __iter__(self):
+    return self.__map.__iter__()
+
+  def get(self, key, default=None):
+    return self.__map.get(key, default)
+
+  def setdefault(self, key, value=None):
+    return self.__map.setdefault(key, value)
+
+  def items(self):
+    return self.__map.items()
+
+  def keys(self):
+    return self.__map.keys()
+
+  def values(self):
+    return self.__map.values()
+
+  def clear(self):
+    self.__map = {}
+
+  def to_dict(self):
+    """Overrides the default IDLNode.to_dict behavior.
+    The IDLDictNode members are copied into a new dictionary, and
+    IDLNode members are recursively converted into dicts as well.
+    """
+    res = {}
+    for (k, v) in self.__map.items():
+      if isinstance(v, IDLNode):
+        v = v.to_dict()
+      res[k] = v
+    return res
+
+  def _all_subnodes(self):
+    # Usually an IDLDictNode does not contain further IDLNodes.
+    return []
+
+
+class IDLFile(IDLNode):
+  """IDLFile is the top-level node in each IDL file. It may contain interfaces."""
+
+  DART_IDL = 'dart.idl'
+
+  def __init__(self, ast, filename=None):
+    IDLNode.__init__(self, ast)
+    self.filename = filename
+
+    filename_basename = os.path.basename(filename)
+
+    self.interfaces = self._convert_all(ast, 'Interface', IDLInterface)
+
+    is_blink = not(isinstance(ast, list)) and ast.__module__ == 'idl_definitions'
+
+    if is_blink:
+      # implements is handled by the interface merging step (see the function
+      # merge_interface_dependencies).
+      for interface in self.interfaces:
+        blink_interface = ast.interfaces.get(interface.id)
+        if filename_basename == self.DART_IDL:
+          # Special handling for dart.idl we need to remember the interface,
+          # since we could have many (not one interface / file). Then build up
+          # the IDLImplementsStatement for any implements in dart.idl.
+          interface_info = interfaces_info['__dart_idl___'];
+
+          self.implementsStatements = []
+
+          implement_pairs = interface_info['implement_pairs']
+          for implement_pair in implement_pairs:
+            interface_name = implement_pair[0]
+            implemented_name = implement_pair[1]
+
+            implementor = new_asts[interface_name].interfaces.get(interface_name)
+            implement_statement = self._createImplementsStatement(implementor,
+                                                                  implemented_name)
+
+            self.implementsStatements.append(implement_statement)
+        else:
+          interface_info = interfaces_info[interface.id]
+
+          implements = interface_info['implements_interfaces']
+          if not(blink_interface.is_partial) and len(implements) > 0:
+            implementor = new_asts[interface.id].interfaces.get(interface.id)
+
+            self.implementsStatements = []
+
+            # TODO(terry): Need to handle more than one implements.
+            for implemented_name in implements:
+              implement_statement = self._createImplementsStatement(implementor,
+                                                                    implemented_name)
+              self.implementsStatements.append(implement_statement)
+          else:
+            self.implementsStatements = []
+    else:
+      self.implementsStatements = self._convert_all(ast, 'ImplStmt',
+        IDLImplementsStatement)
+
+    # No reason to handle typedef they're already aliased in Blink's AST.
+    self.typeDefs = [] if is_blink else self._convert_all(ast, 'TypeDef', IDLTypeDef)
+
+    self.enums = self._convert_all(ast, 'Enum', IDLEnum)
+
+  def _createImplementsStatement(self, implementor, implemented_name):
+    implemented = new_asts[implemented_name].interfaces.get(implemented_name)
+
+    implement_statement = IDLImplementsStatement(implemented)
+
+    implement_statement.implementor = IDLType(implementor)
+    implement_statement.implemented = IDLType(implemented)
+
+    return implement_statement
+
+
+class IDLModule(IDLNode):
+  """IDLModule has an id, and may contain interfaces, type defs and
+  implements statements."""
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+    self._convert_ext_attrs(ast)
+    self._convert_annotations(ast)
+    self.interfaces = self._convert_all(ast, 'Interface', IDLInterface)
+
+    is_blink = ast.__module__ == 'idl_definitions'
+
+    # No reason to handle typedef they're already aliased in Blink's AST.
+    self.typeDefs = [] if is_blink else self._convert_all(ast, 'TypeDef', IDLTypeDef)
+
+    self.enums = self._convert_all(ast, 'Enum', IDLNode)
+
+    if is_blink:
+      # implements is handled by the interface merging step (see the function
+      # merge_interface_dependencies).
+      for interface in self.interfaces:
+        interface_info = interfaces_info[interface.id]
+        # TODO(terry): Same handling for implementsStatements as in IDLFile?
+        self.implementsStatements = interface_info['implements_interfaces']
+    else:
+      self.implementsStatements = self._convert_all(ast, 'ImplStmt',
+        IDLImplementsStatement)
+
+
+class IDLExtAttrs(IDLDictNode):
+  """IDLExtAttrs is an IDLDictNode that stores IDL Extended Attributes.
+  Modules, interfaces, members and arguments can all own IDLExtAttrs."""
+  def __init__(self, ast=None):
+    IDLDictNode.__init__(self, None)
+    if not ast:
+      return
+    if not(isinstance(ast, list)) and ast.__module__ == "idl_definitions":
+      # Pull out extended attributes from Blink AST.
+      for name, value in ast.extended_attributes.items():
+        # TODO(terry): Handle constructors...
+        if name == 'NamedConstructor' or name == 'Constructor':
+          for constructor in ast.constructors:
+            if constructor.name == 'NamedConstructor':
+              constructor_name = ast.extended_attributes['NamedConstructor']
+            else:
+              constructor_name = None
+            func_value = IDLExtAttrFunctionValue(constructor_name, constructor.arguments, True)
+            if name == 'Constructor':
+              self.setdefault('Constructor', []).append(func_value)
+            else:
+              self[name] = func_value
+        else:
+          self[name] = value
+    else:
+      ext_attrs_ast = self._find_first(ast, 'ExtAttrs')
+      if not ext_attrs_ast:
+        return
+      for ext_attr in self._find_all(ext_attrs_ast, 'ExtAttr'):
+        name = self._find_first(ext_attr, 'Id')
+        value = self._find_first(ext_attr, 'ExtAttrValue')
+
+        if name == 'Constructor':
+          # There might be multiple constructor attributes, collect them
+          # as a list.  Represent plain Constructor attribute
+          # (without any signature) as None.
+          assert value is None
+          func_value = None
+          ctor_args = self._find_first(ext_attr, 'ExtAttrArgList')
+          if ctor_args:
+            func_value = IDLExtAttrFunctionValue(None, ctor_args)
+          self.setdefault('Constructor', []).append(func_value)
+          continue
+
+        func_value = self._find_first(value, 'ExtAttrFunctionValue')
+        if func_value:
+          # E.g. NamedConstructor=Audio(optional DOMString src)
+          self[name] = IDLExtAttrFunctionValue(
+              func_value,
+              self._find_first(func_value, 'ExtAttrArgList'))
+          continue
+
+        self[name] = value
+
+  def _all_subnodes(self):
+    # Extended attributes may contain IDLNodes, e.g. IDLExtAttrFunctionValue
+    return self.values()
+
+
+class IDLExtAttrFunctionValue(IDLNode):
+  """IDLExtAttrFunctionValue."""
+  def __init__(self, func_value_ast, arg_list_ast, is_blink=False):
+    IDLNode.__init__(self, func_value_ast)
+    if is_blink:
+      # Blink path
+      self.id = func_value_ast   # func_value_ast is the function name for Blink.
+      self.arguments = []
+      for argument in arg_list_ast:
+        self.arguments.append(IDLArgument(argument))
+    else:
+      self.arguments = self._convert_all(arg_list_ast, 'Argument', IDLArgument)
+
+
+class IDLType(IDLNode):
+  """IDLType is used to describe constants, attributes and operations'
+  return and input types. IDLType matches AST labels such as ScopedName,
+  StringType, VoidType, IntegerType, etc."""
+
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+
+    self.nullable = self._has(ast, 'Nullable')
+    # Search for a 'ScopedName' or any label ending with 'Type'.
+    if isinstance(ast, list):
+      self.id = self._find_first(ast, 'ScopedName')
+      if not self.id:
+        # FIXME: use regexp search instead
+        def findType(ast):
+          for label, childAst in ast:
+            if label.endswith('Type'):
+              type = self._label_to_type(label, ast)
+              if type != 'sequence':
+                return type
+              type_ast = self._find_first(childAst, 'Type')
+              if not type_ast:
+                return type
+              return 'sequence<%s>' % findType(type_ast)
+          raise Exception('No type declaration found in %s' % ast)
+        self.id = findType(ast)
+      # TODO(terry): Remove array_modifiers id has [] appended, keep for old
+      #              parsing.
+      array_modifiers = self._find_first(ast, 'ArrayModifiers')
+      if array_modifiers:
+        self.id += array_modifiers
+    elif isinstance(ast, tuple):
+      (label, value) = ast
+      if label == 'ScopedName':
+        self.id = value
+      else:
+        self.id = self._label_to_type(label, ast)
+    elif isinstance(ast, str):
+      self.id = ast
+    # New blink handling.
+    elif ast.__module__ == "idl_types":
+      if isinstance(ast, IdlType) or isinstance(ast, IdlArrayOrSequenceType):
+        type_name = str(ast)
+
+        # TODO(terry): For now don't handle unrestricted types see
+        #              https://code.google.com/p/chromium/issues/detail?id=354298
+        type_name = type_name.replace('unrestricted ', '', 1);
+
+        # TODO(terry): Handled ScalarValueString as a DOMString.
+        type_name = type_name.replace('ScalarValueString', 'DOMString', 1)
+
+        self.id = type_name
+      else:
+        # IdlUnionType
+        if ast.is_union_type:
+          print 'WARNING type %s is union mapped to \'any\'' % self.id
+        # TODO(terry): For union types use any otherwise type is unionType is
+        #              not found and is removed during merging.
+        self.id = 'any'
+        # TODO(terry): Any union type e.g. 'type1 or type2 or type2',
+        #                            'typedef (Type1 or Type2) UnionType'
+        # Is a problem we need to extend IDLType and IDLTypeDef to handle more
+        # than one type.
+        #
+        # Also for typedef's e.g.,
+        #                 typedef (Type1 or Type2) UnionType
+        # should consider synthesizing a new interface (e.g., UnionType) that's
+        # both Type1 and Type2.
+    if not self.id:
+      print '>>>> __module__ %s' % ast.__module__
+      raise SyntaxError('Could not parse type %s' % (ast))
+
+  def _label_to_type(self, label, ast):
+    if label == 'LongLongType':
+      label = 'long long'
+    elif label.endswith('Type'):
+      # Omit 'Type' suffix and lowercase the rest.
+      label = '%s%s' % (label[0].lower(), label[1:-4])
+
+    # Add unsigned qualifier.
+    if self._has(ast, 'Unsigned'):
+      label = 'unsigned %s' % label
+    return label
+
+
+class IDLEnum(IDLNode):
+  """IDLNode for 'enum [id] { [string]+ }'"""
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+    self._convert_annotations(ast)
+    if not(isinstance(ast, list)) and ast.__module__ == "idl_definitions":
+      # Blink AST
+      self.values = ast.values
+    else:
+      self.values = self._find_all(ast, 'StringLiteral')
+
+    # TODO(terry): Need to handle emitting of enums for dart:html
+
+
+class IDLTypeDef(IDLNode):
+  """IDLNode for 'typedef [type] [id]' declarations."""
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+    self._convert_annotations(ast)
+    self.type = self._convert_first(ast, 'Type', IDLType)
+
+
+class IDLInterface(IDLNode):
+  """IDLInterface node contains operations, attributes, constants,
+  as well as parent references."""
+
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+    self._convert_ext_attrs(ast)
+    self._convert_annotations(ast)
+
+    self.parents = self._convert_all(ast, 'ParentInterface',
+      IDLParentInterface)
+
+    javascript_interface_name = self.ext_attrs.get('InterfaceName', self.id)
+    self.javascript_binding_name = javascript_interface_name
+    self.doc_js_name = javascript_interface_name
+
+    if not (self._find_first(ast, 'Callback') is None):
+      self.ext_attrs['Callback'] = None
+    if not (self._find_first(ast, 'Partial') is None):
+      self.is_supplemental = True
+      self.ext_attrs['DartSupplemental'] = None
+
+    self.operations = self._convert_all(ast, 'Operation',
+      lambda ast: IDLOperation(ast, self.doc_js_name))
+    self.attributes = self._convert_all(ast, 'Attribute',
+      lambda ast: IDLAttribute(ast, self.doc_js_name))
+    self.constants = self._convert_all(ast, 'Const',
+      lambda ast: IDLConstant(ast, self.doc_js_name))
+    self.is_supplemental = 'DartSupplemental' in self.ext_attrs
+    self.is_no_interface_object = 'NoInterfaceObject' in self.ext_attrs
+
+
+  def reset_id(self, new_id):
+    """Reset the id of the Interface and corresponding the JS names."""
+    if self.id != new_id:
+      self.id = new_id
+      self.doc_js_name = new_id
+      self.javascript_binding_name = new_id
+      for member in self.operations:
+        member.doc_js_interface_name = new_id
+      for member in self.attributes:
+        member.doc_js_interface_name = new_id
+      for member in self.constants:
+        member.doc_js_interface_name = new_id
+
+  def has_attribute(self, candidate):
+    for attribute in self.attributes:
+      if (attribute.id == candidate.id and
+          attribute.is_read_only == candidate.is_read_only):
+        return True
+    return False
+
+
+class IDLParentInterface(IDLNode):
+  """This IDLNode specialization is for 'Interface Child : Parent {}'
+  declarations."""
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+    self._convert_annotations(ast)
+    self.type = self._convert_first(ast, 'InterfaceType', IDLType)
+
+
+class IDLMember(IDLNode):
+  """A base class for constants, attributes and operations."""
+
+  def __init__(self, ast, doc_js_interface_name):
+    IDLNode.__init__(self, ast)
+
+    self.type = self._convert_first(ast, 'Type', IDLType)
+    self._convert_ext_attrs(ast)
+    self._convert_annotations(ast)
+    self.doc_js_interface_name = doc_js_interface_name
+    self.is_static = self._has(ast, 'Static')
+
+
+class IDLOperation(IDLMember):
+  """IDLNode specialization for 'type name(args)' declarations."""
+  def __init__(self, ast, doc_js_interface_name):
+    IDLMember.__init__(self, ast, doc_js_interface_name)
+
+    self.type = self._convert_first(ast, 'ReturnType', IDLType)
+    self.arguments = self._convert_all(ast, 'Argument', IDLArgument)
+    self.specials = self._find_all(ast, 'Special')
+    # Special case: there are getters of the form
+    # getter <ReturnType>(args).  For now force the name to be __getter__,
+    # but it should be operator[] later.
+    if self.id is None:
+      if self.specials == ['getter']:
+        if self.ext_attrs.get('Custom') == 'PropertyQuery':
+          # Handling __propertyQuery__ the extended attribute is:
+          # [Custom=PropertyQuery] getter boolean (DOMString name);
+          self.id = '__propertyQuery__'
+        else:
+          self.id = '__getter__'
+      elif self.specials == ['setter']:
+        self.id = '__setter__'
+        # Special case: if it's a setter, ignore 'declared' return type
+        self.type = IDLType([('VoidType', None)])
+      elif self.specials == ['deleter']:
+        self.id = '__delete__'
+      else:
+        raise Exception('Cannot handle %s: operation has no id' % ast)
+
+      if len(self.arguments) >= 1 and (self.id in _operation_suffix_map) and not self.ext_attrs.get('ImplementedAs'):
+        arg = self.arguments[0]
+        operation_category = 'Named' if arg.type.id == 'DOMString' else 'Indexed'
+        self.ext_attrs.setdefault('ImplementedAs', 'anonymous%s%s' % (operation_category, _operation_suffix_map[self.id]))
+
+  def _extra_repr(self):
+    return [self.arguments]
+
+  def SameSignatureAs(self, operation):
+    if self.type != operation.type:
+      return False
+    return [a.type for a in self.arguments] == [a.type for a in operation.arguments]
+
+class IDLAttribute(IDLMember):
+  """IDLNode specialization for 'attribute type name' declarations."""
+  def __init__(self, ast, doc_js_interface_name):
+    IDLMember.__init__(self, ast, doc_js_interface_name)
+    self.is_read_only = self._has(ast, 'ReadOnly')
+    # There are various ways to define exceptions for attributes:
+
+  def _extra_repr(self):
+    extra = []
+    if self.is_read_only: extra.append('readonly')
+    return extra
+
+
+class IDLConstant(IDLMember):
+  """IDLNode specialization for 'const type name = value' declarations."""
+  def __init__(self, ast, doc_js_interface_name):
+    IDLMember.__init__(self, ast, doc_js_interface_name)
+    self.value = self._find_first(ast, 'ConstExpr')
+
+
+class IDLArgument(IDLNode):
+  """IDLNode specialization for operation arguments."""
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+
+    self.default_value = None
+    self.default_value_is_null = False
+    # Handle the 'argType arg = default'. IDL syntax changed from
+    # [default=NullString].
+    if not isinstance(ast, list):
+      if isinstance(ast.default_value, idl_definitions.IdlLiteral) and ast.default_value:
+        self.default_value = ast.default_value.value
+        self.default_value_is_null = ast.default_value.is_null
+      elif 'Default' in ast.extended_attributes:
+        # Work around [Default=Undefined] for arguments - only look in the model's
+        # default_value
+        self.default_value = ast.extended_attributes.get('Default')
+        self.default_value_is_null = False
+
+    self.type = self._convert_first(ast, 'Type', IDLType)
+    self.optional = self._has(ast, 'Optional')
+    self._convert_ext_attrs(ast)
+    # TODO(vsm): Recover this from the type instead.
+    if 'Callback' in self.type.id:
+      self.ext_attrs['Callback'] = None
+
+  def __repr__(self):
+    return '<IDLArgument(type = %s, id = %s)>' % (self.type, self.id)
+
+
+class IDLImplementsStatement(IDLNode):
+  """IDLNode specialization for 'IMPLEMENTOR implements IMPLEMENTED' declarations."""
+  def __init__(self, ast):
+    IDLNode.__init__(self, ast)
+    if isinstance(ast, list) or ast.__module__ != 'idl_definitions':
+      self.implementor = self._convert_first(ast, 'ImplStmtImplementor', IDLType)
+      self.implemented = self._convert_first(ast, 'ImplStmtImplemented', IDLType)
+
+
+class IDLAnnotations(IDLDictNode):
+  """IDLDictNode specialization for a list of FremontCut annotations."""
+  def __init__(self, ast=None):
+    IDLDictNode.__init__(self, ast)
+    self.id = None
+    if not ast:
+      return
+    for annotation in self._find_all(ast, 'Annotation'):
+      name = self._find_first(annotation, 'Id')
+      value = IDLAnnotation(annotation)
+      self[name] = value
+
+
+class IDLAnnotation(IDLDictNode):
+  """IDLDictNode specialization for one annotation."""
+  def __init__(self, ast=None):
+    IDLDictNode.__init__(self, ast)
+    self.id = None
+    if not ast:
+      return
+    for arg in self._find_all(ast, 'AnnotationArg'):
+      name = self._find_first(arg, 'Id')
+      value = self._find_first(arg, 'AnnotationArgValue')
+      self[name] = value