IDL: Generate union type containers

Source/bindings/templates/methods.cpp

 {##############################################################################}
 {% macro generate_method(method, world_suffix) %}
 {% filter conditional(method.conditional_string) %}
 static void {{method.name}}{{method.overload_index}}Method{{world_suffix}}(const v8::FunctionCallbackInfo<v8::Value>& info)
 {
     {# Local variables #}
     {% if method.has_exception_state %}
     ExceptionState exceptionState(ExceptionState::ExecutionContext, "{{method.name}}", "{{interface_name}}", info.Holder(), info.GetIsolate());
     {% endif %}
     {# Overloaded methods have length checked during overload resolution #}
@@ skipping 220 matching lines @@
 {{cpp_value}};
 {% elif method.is_implemented_in_private_script %}
 {{method.cpp_type}} result{{method.cpp_type_initializer}};
 if (!{{method.cpp_value}})
     return;
 {% elif method.use_output_parameter_for_result %}
 {{method.cpp_type}} result;
 {{cpp_value}};
 {% elif method.is_constructor %}
 {{method.cpp_type}} impl = {{cpp_value}};
-{% elif method.use_local_result and not method.union_arguments %}
+{% elif method.use_local_result and not method.union_result_members %}
 {{method.cpp_type}} result = {{cpp_value}};
 {% endif %}
 {# Post-call #}
 {% if method.is_raises_exception %}
 if (exceptionState.hadException()) {
     {{throw_from_exception_state(method)}};
     return;
 }
 {% endif %}
 {# Set return value #}
 {% if method.is_constructor %}
 {{generate_constructor_wrapper(method)}}
-{%- elif method.union_arguments %}
+{%- elif method.union_result_members %}
 {{union_type_method_call_and_set_return_value(method)}}
 {%- elif v8_set_return_value %}
 {% if method.is_explicit_nullable %}
 if (result.isNull())
     v8SetReturnValueNull(info);
 else
     {{v8_set_return_value}};
 {% else %}
 {{v8_set_return_value}};
 {% endif %}
 {%- endif %}{# None for void #}
 {# Post-set #}
 {% if interface_name in ('EventTarget', 'MediaQueryList')
     and method.name in ('addEventListener', 'removeEventListener', 'addListener', 'removeListener') %}
 {% set hidden_dependency_action = 'addHiddenValueToArray'
        if method.name in ('addEventListener', 'addListener') else 'removeHiddenValueFromArray' %}
 {% set argument_index = '1' if interface_name == 'EventTarget' else '0' %}
 {# Length check needed to skip action on legacy calls without enough arguments.
    http://crbug.com/353484 #}
 if (info.Length() >= {{argument_index}} + 1 && listener && !impl->toNode())
     {{hidden_dependency_action}}(info.GetIsolate(), info.Holder(), info[{{argument_index}}], {{v8_class}}::eventListenerCacheIndex);
 {% endif %}
 {% endmacro %}
 
 
 {######################################}
 {% macro union_type_method_call_and_set_return_value(method) %}

[Jens Widell, 2014/10/28 11:31:38]

Could the scope of this macro now be reduced to just dealing with the return
value after the call? We already have generic handling of declaring a 'result'
local and passing it as an argument in the call above.

Or, better yet (perhaps), could we simply generate a per-union-type
v8SetReturnValue() method, and completely (?) eliminate the need for any special
code for union return types?

[bashi, 2014/10/29 01:34:32]

Took the later approach, and removed special code for union types from this
template:) Thank you for the suggestion!

-{% for argument in method.union_arguments %}
-{{argument.cpp_type}} {{argument.cpp_value}}{{argument.cpp_type_initializer}};
-{% endfor %}
+{{method.cpp_type}} result;
 {{method.cpp_value}};
 {% if method.is_null_expression %}{# used by getters #}
 if ({{method.is_null_expression}})
     return;
 {% endif %}
-{% for argument in method.union_arguments %}
-if ({{argument.null_check_value}}) {
-    {{argument.v8_set_return_value}};
+{% for member in method.union_result_members %}
+if ({{member.null_check_value}}) {
+    {{member.v8_set_return_value}};
     return;
 }
 {% endfor %}
 {# Fall back to null if none of the union members results are returned #}
 {% if method.is_null_expression %}
 ASSERT_NOT_REACHED();
 {% else %}
 v8SetReturnValueNull(info);
 {% endif %}
 {% endmacro %}
@@ skipping 353 matching lines @@
     {% for method in conditionally_enabled_methods %}
     {% filter per_context_enabled(method.per_context_enabled_function) %}
     {% filter exposed(method.exposed_test) %}
     prototypeObject->Set(v8AtomicString(isolate, "{{method.name}}"), v8::FunctionTemplate::New(isolate, {{cpp_class_or_partial}}V8Internal::{{method.name}}MethodCallback, v8Undefined(), defaultSignature, {{method.number_of_required_arguments}})->GetFunction());
     {% endfilter %}
     {% endfilter %}
     {% endfor %}
     {% endif %}
 }
 {%- endmacro %}