Make more native DOM array-like objects known to compiler.

lib/dom/scripts/systemhtml.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
 
@@ skipping 788 matching lines @@
 
     native_spec = MakeNativeSpec(interface.javascript_binding_name)
 
     extends = ' extends ' + base if base else ''
 
     # TODO: Include all implemented interfaces, including other Lists.
     implements = [self._html_interface_name]
     element_type = MaybeTypedArrayElementType(self._interface)
     if element_type:
       implements.append('List<%s>' % self._DartType(element_type))
+
+    if self._HasJavaScriptIndexingBehaviour():
       implements.append('JavaScriptIndexingBehavior')
 
     template_file = 'impl_%s.darttemplate' % self._html_interface_name
     template = (self._system._templates.TryLoad(template_file) or
                 self._system._templates.Load('dart2js_impl.darttemplate'))
     self._members_emitter = self._dart_code.Emit(
         template,
         #class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
         #$!MEMBERS
         #}
@@ skipping 173 matching lines @@
           '  $TYPE $NAME($PARAMS) native;\n',
           TYPE=self._NarrowOutputType(info.type_name),
           NAME=info.name,
           PARAMS=info.ParametersImplementationDeclaration(
               lambda type_name: self._NarrowInputType(type_name)))
 
   def _HasCustomImplementation(self, member_name):
     member_name = '%s.%s' % (self._html_interface_name, member_name)
     return member_name in _js_custom_members
 
+  def _HasJavaScriptIndexingBehaviour(self):
+    """Returns True if the native object has an indexer and length property."""
+    (element_type, requires_indexer) = ListImplementationInfo(
+      self._interface, self._database)

[kasperl, 2012/08/02 10:03:06]

4 space indent here?

[sra1, 2012/08/02 10:26:51]

Done.

+    if element_type and requires_indexer: return True
+    return False
+
 # ------------------------------------------------------------------------------
 
 class HtmlDart2JSSystem(System):
 
   def __init__(self, options):
     super(HtmlDart2JSSystem, self).__init__(options)
 
   def ImplementationGenerator(self, interface):
     return HtmlDart2JSClassGenerator(self, interface)
 
   def GenerateLibraries(self, dart_files):
     self._GenerateLibFile(
         'html_dart2js.darttemplate',
         os.path.join(self._output_dir, 'html_dart2js.dart'),
         dart_files)
 
   def Finish(self):
     pass