IDL: Generate union type containers

Source/bindings/templates/union.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// FIXME: Implement
+// This file has been auto-generated by {{code_generator}}. DO NOT MODIFY!
+
+#include "config.h"
+#include "{{header_filename}}"
+
+{% for filename in cpp_includes %}
+#include "{{filename}}"
+{% endfor %}
+
+namespace blink {
+
+{% for container in containers %}
+{{container.cpp_class}}::{{container.cpp_class}}()
+    : m_specificType(SpecificTypeNone)
+{
+}
+
+{% for member in container.members %}
+{{member.rvalue_cpp_type}} {{container.cpp_class}}::getAs{{member.type_name}}()
+{
+    ASSERT(is{{member.type_name}}());
+    return m_{{member.cpp_name}};
+}
+
+void {{container.cpp_class}}::set{{member.type_name}}({{member.rvalue_cpp_type}} value)
+{
+    ASSERT(isNull());
+    m_{{member.cpp_name}} = value;
+    m_specificType = {{member.specific_type_enum}};
+}
+
+{% endfor %}
+void V8{{container.cpp_class}}::toImpl(v8::Isolate* isolate, v8::Handle<v8::Value> v8Value, {{container.cpp_class}}& impl, ExceptionState& exceptionState)
+{
+    {# FIXME: We doesn't follow the spec on handling null and undefined at this

[Jens Widell, 2014/10/29 07:18:51]

"We don't" :-)

[bashi, 2014/10/29 09:57:36]

Done. Thank you for always correcting my poor English :)

+       moment. Should be fixed once we implement all necessary conversion steps
+       below. #}
+    if (v8Value.IsEmpty() || isUndefinedOrNull(v8Value))
+        return;
+
+    {# The numbers in the following comments refer the steps described in
+       http://heycam.github.io/webidl/#es-union
+       FIXME: Implement all necessary steps #}
+    {# 3. Platform objects (interfaces) #}
+    {% for interface in container.interface_types %}
+    if (V8{{interface.type_name}}::hasInstance(v8Value, isolate)) {
+        {{interface.cpp_type}} cppValue = V8{{interface.type_name}}::toImpl(v8::Handle<v8::Object>::Cast(v8Value));
+        impl.set{{interface.type_name}}(cppValue);
+        return;
+    }
+
+    {% endfor %}
+    {% if container.dictionary_type %}
+    {# 12. Dictionaries #}
+    {# FIXME: This should be "object but not Date or RegExp". Adds checks when
+       we implement conversions for Date and RegExp. #}
+    if (v8Value->IsObject()) {
+        {{container.dictionary_type.cpp_type}} cppValue = V8{{container.dictionary_type.type_name}}::toImpl(isolate, v8Value, exceptionState);
+        if (!exceptionState.hadException())
+            impl.set{{container.dictionary_type.type_name}}(cppValue);
+        return;
+    }
+
+    {% endif %}
+    {% if container.boolean_type %}
+    {# 14. Boolean #}
+    if (v8Value->IsBoolean()) {
+        impl.setBoolean(v8Value->ToBoolean()->Value());
+        return;
+    }
+
+    {% endif %}
+    {% if container.numeric_type %}
+    {# 15. Number #}
+    if (v8Value->IsNumber()) {
+        {{container.numeric_type.v8_value_to_local_cpp_value}};
+        impl.set{{container.numeric_type.type_name}}(cppValue);
+        return;
+    }
+
+    {% endif %}
+    {% if container.string_type %}
+    {# 16. String #}
+    {
+        {{container.string_type.v8_value_to_local_cpp_value}};
+        impl.set{{container.string_type.type_name}}(cppValue);
+        return;
+    }
+
+    {% endif %}
+    {# 17. Number (fallback) #}
+    {% if container.numeric_type %}

[Jens Widell, 2014/10/29 07:18:51]

Use "elif" instead here (and for boolean)? We only need the unconditional
fallback code for one of string, number and boolean.

The C++ compiler would of course eliminate the extra (dead) code, but since we
don't need any complicated logic here to only generate one of the fallbacks, we
might as well do it.

(We could also skip the IsBoolean()/IsNumber() checks above when we'd fall back
to that type anyway, but that of course takes a little bit more logic to do.)

[bashi, 2014/10/29 09:57:36]

Done. I'd like to keep fallback logic at this time for simplicity.

+    {
+        {{container.numeric_type.v8_value_to_local_cpp_value}};
+        return;
+    }
+
+    {% endif %}
+    {# 18. Boolean (fallback) #}
+    {% if container.boolean_type %}
+    {
+        impl.setBoolean(v8Value->ToBoolean()->Value());
+        return;
+    }
+
+    {% endif %}
+    {# 19. TypeError #}
+    exceptionState.throwTypeError("Not a valid union member.");
+}
+
+v8::Handle<v8::Value> toV8({{container.cpp_class}}& impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
+{
+    if (impl.isNull())
+        return v8::Null(isolate);
+
+    {% for member in container.members %}
+    if (impl.is{{member.type_name}}())
+        return {{member.cpp_value_to_v8_value}};
+
+    {% endfor %}
+    ASSERT_NOT_REACHED();
+    return v8::Null(isolate);
+}
+
+{% endfor %}
+} // namespace blink