Reapply Futureification.

tools/dom/scripts/htmldartgenerator.py

 #!/usr/bin/python
 # Copyright (c) 2012, 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.
 
 """This module provides shared functionality for the system to generate
 dart:html APIs from the IDL database."""
 
 import emitter
 from generator import AnalyzeOperation, ConstantOutputOrder, \
     DartDomNameOfAttribute, FindMatchingAttribute, IsDartCollectionType, \
     IsPureInterface, TypeOrNothing, GetAnnotationsAndComments, \
-    FormatAnnotationsAndComments
+    FormatAnnotationsAndComments, ConvertToFuture, GetCallbackInfo
+from htmlrenamer import convert_to_future_members
 
 # Types that are accessible cross-frame in a limited fashion.
 # In these cases, the base type (e.g., WindowBase) provides restricted access
 # while the subtype (e.g., Window) provides full access to the
 # corresponding objects if there are from the same frame.
 _secure_base_types = {
   'Window': 'WindowBase',
   'Location': 'LocationBase',
   'History': 'HistoryBase',
 }
@@ skipping 58 matching lines @@
     for operation in interface.operations:
       if operation.id not in operationsById:
         operationsById[operation.id] = []
       operationsById[operation.id].append(operation)
 
     # Generate operations.
     for id in sorted(operationsById.keys()):
       operations = operationsById[id]
       info = AnalyzeOperation(interface, operations)
       self.AddOperation(info, declare_only)
+      if ('%s.%s' % (interface.id, info.declared_name) in
+          convert_to_future_members):
+        self.AddOperation(ConvertToFuture(info), declare_only)
 
   def AddSecondaryMembers(self, interface):
     # With multiple inheritance, attributes and operations of non-first
     # interfaces need to be added.  Sometimes the attribute or operation is
     # defined in the current interface as well as a parent.  In that case we
     # avoid making a duplicate definition and pray that the signatures match.
     secondary_parents = self._TransitiveSecondaryParents(interface)
     for parent_interface in sorted(secondary_parents):
       if isinstance(parent_interface, str):
         continue
@@ skipping 345 matching lines @@
           constructor_info.idl_args,
           False,
           [info.name for info in constructor_info.param_infos],
           emitter.Format('$(ANNOTATIONS)factory $CTOR($PARAMS)',
             CTOR=constructor_info._ConstructorFullName(self._DartType),
             ANNOTATIONS=annotations,
             PARAMS=constructor_info.ParametersDeclaration(self._DartType)),
           GenerateCall,
           IsOptional)
 
+  def _AddFutureifiedOperation(self, info, html_name):
+    """Given a API function that uses callbacks, convert it to using Futures.
+
+    This conversion assumes the success callback is always provided before the
+    error callback (and so far in the DOM API, this is the case)."""
+    callback_info = GetCallbackInfo(
+        self._database.GetInterface(info.callback_args[0].type_id))
+
+    param_list = info.ParametersAsArgumentList()
+    annotations = ''
+    if '_RenamingAnnotation' in dir(self):
+      annotations = (self._RenamingAnnotation(info.declared_name, html_name) +
+          self._Annotations(info.type_name, info.declared_name))
+    self._members_emitter.Emit(
+        '\n'
+        '  $ANNOTATIONS$MODIFIERS$TYPE$FUTURE_GENERIC $NAME($PARAMS) {\n'
+        '    var completer = new Completer$(FUTURE_GENERIC)();\n'
+        '    $ORIGINAL_FUNCTION($PARAMS_LIST\n'
+        '        $NAMED_PARAM($VARIABLE_NAME) { '
+        'completer.complete($VARIABLE_NAME); }'
+        '$ERROR_CALLBACK);\n'
+        '    return completer.future;\n'
+        '  }\n',
+        ANNOTATIONS=annotations,
+        MODIFIERS='static ' if info.IsStatic() else '',
+        TYPE=self.SecureOutputType(info.type_name),
+        NAME=html_name[1:],
+        PARAMS=info.ParametersDeclaration(self._NarrowInputType
+            if '_NarrowInputType' in dir(self) else self._DartType),
+        PARAMS_LIST='' if param_list == '' else param_list + ',',
+        NAMED_PARAM=('%s : ' % info.callback_args[0].name
+            if info.requires_named_arguments and
+              info.callback_args[0].is_optional else ''),
+        VARIABLE_NAME= '' if len(callback_info.param_infos) == 0 else 'value',
+        ERROR_CALLBACK=('' if len(info.callback_args) == 1 else
+            (',\n        %s(error) { completer.completeError(error); }' %
+            ('%s : ' % info.callback_args[1].name
+            if info.requires_named_arguments and
+                info.callback_args[1].is_optional else ''))),
+        FUTURE_GENERIC = ('' if len(callback_info.param_infos) == 0 or
+            not callback_info.param_infos[0].type_id else
+            '<%s>' % self._DartType(callback_info.param_infos[0].type_id)),
+        ORIGINAL_FUNCTION = html_name)
+
   def EmitHelpers(self, base_class):
     pass
 
   def DeclareAttribute(self, attribute, type_name, attr_name, read_only):
     """ Declares an attribute but does not include the code to invoke it.
     """
     if read_only:
       template = '\n  $TYPE get $NAME;\n'
     else:
       template = '\n  $TYPE $NAME;\n'
@@ skipping 88 matching lines @@
         walk(interface.parents)
       else:
         walk(interface.parents[1:])
     return result
 
   def _DartType(self, type_name):
     return self._type_registry.DartType(type_name)
 
   def _IsPrivate(self, name):
     return name.startswith('_')