IDL: Support extended attributes on iterable<>, maplike<> and setlike<>

Source/bindings/scripts/v8_interface.py

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 # coding=utf-8
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@@ skipping 324 matching lines @@
     # [Iterable], iterable<>, maplike<> and setlike<>
     iterator_method = None
     # FIXME: support Iterable in partial interfaces. However, we don't
     # need to support iterator overloads between interface and
     # partial interface definitions.
     # http://heycam.github.io/webidl/#idl-overloading
     if (not interface.is_partial
         and (interface.iterable or interface.maplike or interface.setlike
              or 'Iterable' in extended_attributes)):
 
+        use_extended_attributes = {}

[haraken, 2015/01/14 11:38:47]

used_extended_attributes ?

[Jens Widell, 2015/01/14 11:50:45]

Works too. :-)

[Jens Widell, 2015/01/14 12:00:02]

Done.

+
+        if interface.iterable:
+            use_extended_attributes.update(interface.iterable.extended_attributes)
+        elif interface.maplike:

[haraken, 2015/01/14 11:38:47]

elif => if ?

[Jens Widell, 2015/01/14 11:50:45]

Wouldn't change behavior, since there can only be one of iterable, maplike and
setlike. It would give the impression that there could be, though, so I think I
prefer elif here.

[haraken, 2015/01/14 12:53:33]

Makes sense.

+            use_extended_attributes.update(interface.maplike.extended_attributes)
+        elif interface.setlike:

[haraken, 2015/01/14 11:38:47]

elif => if ?

+            use_extended_attributes.update(interface.setlike.extended_attributes)
+
+        if 'RaisesException' not in use_extended_attributes:
+            use_extended_attributes['RaisesException'] = None
+        if 'CallWith' not in use_extended_attributes:
+            use_extended_attributes['CallWith'] = 'ScriptState'

[haraken, 2015/01/14 11:38:47]

This rule looks a bit hacky. Do we need to support other than ScriptState?
(ScriptState is the most general and modern (?) way to pass script information
to the Blink side.)

[Jens Widell, 2015/01/14 11:50:45]

We don't need it right now, for sure, since there's hardly any code that uses
this. And I suppose there's no compelling reason to support it at all given that
ScriptState covers all the other candidates rather well.

I could change this code to just check that RaisesException and CallWith aren't
included in the extended attributes (since they have fixed values) and then
unconditionally override them.

+
         def generated_iterator_method(name):
             return generated_method(
                 return_type=IdlType('Iterator'),
                 name=name,
-                extended_attributes={'RaisesException': None, 'CallWith': 'ScriptState'})
+                extended_attributes=use_extended_attributes)
 
         iterator_method = generated_iterator_method('iterator')
 
         if interface.iterable:
             methods.extend([
                 generated_iterator_method('keys'),
                 generated_iterator_method('values'),
                 generated_iterator_method('entries'),
             ])
 
@@ skipping 927 matching lines @@
         deleter = next(
             method
             for method in interface.operations
             if ('deleter' in method.specials and
                 len(method.arguments) == 1 and
                 str(method.arguments[0].idl_type) == 'DOMString'))
     except StopIteration:
         return None
 
     return property_deleter(deleter)