IDL: Add forEach() method to iterable<>/maplike<>/setlike<> interfaces

Source/bindings/scripts/v8_utilities.py

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@@ skipping 183 matching lines @@
 
 
 # [CallWith]
 CALL_WITH_ARGUMENTS = {
     'ScriptState': 'scriptState',
     'ExecutionContext': 'executionContext',
     'ScriptArguments': 'scriptArguments.release()',
     'ActiveWindow': 'callingDOMWindow(info.GetIsolate())',
     'FirstWindow': 'enteredDOMWindow(info.GetIsolate())',
     'Document': 'document',
+    'ThisValue': 'ScriptValue(scriptState, info.This())',

[haraken, 2015/01/27 01:56:30]

Just to confirm: Are you sure that we should use info.This(), not info.Holder()?

[Jens Widell, 2015/01/27 07:19:23]

No, I'm not sure. What's the difference between the two, exactly?

Technically, we could do without this altogether. Iterable<> would just need a
way to "find itself," since it's a mixin class and not a ScriptWrappable.
Something like

  virtual v8::Local<v8::Object> getThis() = 0;

or such would work. I figured this [CallWith=ThisValue] approach would be
simpler.

[haraken, 2015/01/27 08:47:11]

info.Holder() points to a reciever, and info.This() points to an object on which
the DOM attribute/method exists. For example, in a case of div.appendChild(),
info.Holder() points to the div, and info.This() points to
div.__proto__.__proto__.__proto__.__proto__, on which the appendChild is
defined.

 }
 # List because key order matters, as we want arguments in deterministic order
 CALL_WITH_VALUES = [
     'ScriptState',
     'ExecutionContext',
     'ScriptArguments',
     'ActiveWindow',
     'FirstWindow',
     'Document',
+    'ThisValue',
 ]
 
 
 def call_with_arguments(call_with_values):
     if not call_with_values:
         return []
     return [CALL_WITH_ARGUMENTS[value]
             for value in CALL_WITH_VALUES
             if extended_attribute_value_contains(call_with_values, value)]
 
@@ skipping 167 matching lines @@
 
     The returned function checks if a method/attribute is enabled.
     Given extended attribute RuntimeEnabled=FeatureName, return:
         RuntimeEnabledFeatures::{featureName}Enabled
     """
     extended_attributes = definition_or_member.extended_attributes
     if 'RuntimeEnabled' not in extended_attributes:
         return None
     feature_name = extended_attributes['RuntimeEnabled']
     return 'RuntimeEnabledFeatures::%sEnabled' % uncapitalize(feature_name)