Enable the WebIDL [Exposed] annotation on an interface's members.

Source/bindings/scripts/v8_utilities.py

Index: Source/bindings/scripts/v8_utilities.py
diff --git a/Source/bindings/scripts/v8_utilities.py b/Source/bindings/scripts/v8_utilities.py
index 674a1b8d9969b08a53404147c1c7e289db1f73f4..4c2dbbb32652f574ef04ab49c065e124f59494a5 100644
--- a/Source/bindings/scripts/v8_utilities.py
+++ b/Source/bindings/scripts/v8_utilities.py
@@ -74,6 +74,15 @@ def has_extended_attribute_value(definition_or_member, name, value):
             extended_attribute_value_contains(extended_attributes[name], value))
 
 
+def sorted_extended_attribute_list(definition_or_member, name):
+    extended_attributes = definition_or_member.extended_attributes
+    if name not in extended_attributes:
+        return []
+
+    attribute_values = re.split('[|&]', extended_attributes[name])
+    return sorted(attribute_values)
+
+
 ################################################################################
 # String handling
 ################################################################################
@@ -225,6 +234,48 @@ def deprecate_as(member):
     return extended_attributes['DeprecateAs']
 
 
+# [Exposed]
+EXPOSED_EXECUTION_CONTEXT_METHOD = {
+    'DedicatedWorker': 'isDedicatedWorkerGlobalScope',
+    'ServiceWorker': 'isServiceWorkerGlobalScope',
+    'SharedWorker': 'isSharedWorkerGlobalScope',
+    'Window': 'isDocument',
+    'Worker': 'isWorkerGlobalScope',
+}
+
+def exposed(definition_or_member, interface):
+    extended_attributes = definition_or_member.extended_attributes

[Jens Widell, 2014/07/30 16:48:45]

This local is only used once, on the line below, and is thus rather unnecessary.
And the check below could be done on 'exposure_list' instead:

  if not exposure_list:
    return None

[Peter Beverloo, 2014/07/31 19:02:21]

Done.

+    if 'Exposed' not in extended_attributes:
+        return None
+
+    exposure_list = sorted_extended_attribute_list(definition_or_member, 'Exposed')

[Jens Widell, 2014/07/30 16:48:45]

I think you could have stuck with 'exposure_set' here; it's still logically a
set of something, even if we use a Python list to represent it.

The suffix switch indicates that the suffix was actually just an explicit record
of the type of the stored value, and such are rarely useful IMO, in particular
not for something with a scope this limited.

We could also just call it 'exposure'.

This comment could also just be considered as noise. :-)

[Peter Beverloo, 2014/07/31 19:02:21]

I'm in dubio. It would indeed describe the contents accurately (a sorted set),
but it could cause some confusion since the Python data type in fact is a list.

Let's go with following the contents -- thanks!

+    interface_exposure_list = expanded_exposure_list_for_interface(interface)
+
+    # Methods must not be exposed to a broader scope than their interface.
+    if not set(exposure_list).issubset(interface_exposure_list):
+        raise Exception('Interface members\' exposure sets must be a subset of the interface\'s.')

[haraken, 2014/07/30 16:32:03]

Nit: We normally use ValueError instead of Exception.

[Peter Beverloo, 2014/07/31 19:02:22]

Done.

+
+    exposure_checks = []
+    for environment in exposure_list:
+        # Methods must be exposed on one of the scopes known to Blink.
+        if environment not in EXPOSED_EXECUTION_CONTEXT_METHOD:
+            raise Exception('Values for the [Exposed] annotation must reflect to a valid exposure scope.')

[haraken, 2014/07/30 16:32:03]

Ditto.

[Peter Beverloo, 2014/07/31 19:02:22]

Done.

+
+        exposure_checks.append('context->%s()' % EXPOSED_EXECUTION_CONTEXT_METHOD[environment])
+
+    return ' || '.join(exposure_checks)
+
+
+def expanded_exposure_list_for_interface(interface):
+    exposure_list = sorted_extended_attribute_list(interface, 'Exposed')
+
+    # "Worker" is an aggregation for the different kinds of workers.
+    if 'Worker' in exposure_list:
+        exposure_list.extend(('DedicatedWorker', 'SharedWorker', 'ServiceWorker'))
+
+    return sorted(set(exposure_list))
+
+
 # [GarbageCollected], [WillBeGarbageCollected]
 def gc_type(definition):
     extended_attributes = definition.extended_attributes