IDL: Generate union type containers

Source/bindings/scripts/v8_types.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 174 matching lines @@
         return idl_type.implemented_as + '*'
     if idl_type.is_interface_type:
         implemented_as_class = idl_type.implemented_as
         if raw_type:
             return implemented_as_class + '*'
         new_type = 'Member' if used_in_cpp_sequence else 'RawPtr'
         ptr_type = cpp_ptr_type(('PassRefPtr' if used_as_rvalue_type else 'RefPtr'), new_type, idl_type.gc_type)
         return cpp_template_type(ptr_type, implemented_as_class)
     if idl_type.is_dictionary:
         return base_idl_type
+    if idl_type.is_union_type:
+        return idl_type.name
+
     # Default, assume native type is a pointer with same type name as idl type
     return base_idl_type + '*'
 
 
 def cpp_type_initializer(idl_type):
     """Returns a string containing a C++ initialization statement for the
     corresponding type.
 
     |idl_type| argument is of type IdlType.
     """
 
     base_idl_type = idl_type.base_type
 
     if idl_type.native_array_element_type:
         return ''
     if idl_type.is_numeric_type:
         return ' = 0'
     if base_idl_type == 'boolean':
         return ' = false'
     if (base_idl_type in NON_WRAPPER_TYPES or
         base_idl_type in CPP_SPECIAL_CONVERSION_RULES or
         base_idl_type == 'any' or
         idl_type.is_string_type or
         idl_type.is_enum):
         return ''
     return ' = nullptr'
 
 
-def cpp_type_union(idl_type, extended_attributes=None, raw_type=False):
-    # FIXME: Need to revisit the design of union support.
-    # http://crbug.com/240176
-    return None
-
-
-def cpp_type_initializer_union(idl_type):
-    return (member_type.cpp_type_initializer for member_type in idl_type.member_types)
-
-
 # Allow access as idl_type.cpp_type if no arguments
 IdlTypeBase.cpp_type = property(cpp_type)
 IdlTypeBase.cpp_type_initializer = property(cpp_type_initializer)
 IdlTypeBase.cpp_type_args = cpp_type
-IdlUnionType.cpp_type = property(cpp_type_union)
-IdlUnionType.cpp_type_initializer = property(cpp_type_initializer_union)
-IdlUnionType.cpp_type_args = cpp_type_union
+IdlUnionType.cpp_type_initializer = ''
 
 
 IdlArrayOrSequenceType.native_array_element_type = property(
     lambda self: self.element_type)
 
 
 def cpp_template_type(template, inner_type):
     """Returns C++ template specialized to type, with space added if needed."""
     if inner_type.endswith('>'):
         format_string = '{template}<{inner_type} >'
@@ skipping 227 matching lines @@
 }
 
 
 def v8_conversion_needs_exception_state(idl_type):
     return (idl_type.is_numeric_type or
             idl_type.is_dictionary or
             idl_type.name in ('ByteString', 'USVString', 'SerializedScriptValue'))
 
 IdlType.v8_conversion_needs_exception_state = property(v8_conversion_needs_exception_state)
 IdlArrayOrSequenceType.v8_conversion_needs_exception_state = True
+IdlUnionType.v8_conversion_needs_exception_state = True
 
 
 TRIVIAL_CONVERSIONS = frozenset([
     'any',
     'boolean',
     'Date',
     'Dictionary',
     'NodeFilter',
     'XPathNSResolver',
     'Promise'
@@ skipping 64 matching lines @@
         expression_format = '(to{ref_ptr_type}NativeArray<{native_array_element_type}, V8{native_array_element_type}>({v8_value}, {index}, {isolate}, exceptionState))'
         add_includes_for_type(native_array_element_type)
     else:
         ref_ptr_type = None
         this_cpp_type = native_array_element_type.cpp_type
         expression_format = 'toImplArray<{cpp_type}>({v8_value}, {index}, {isolate}, exceptionState)'
     expression = expression_format.format(native_array_element_type=native_array_element_type.name, cpp_type=this_cpp_type, index=index, ref_ptr_type=ref_ptr_type, v8_value=v8_value, isolate=isolate)
     return expression
 
 
-def v8_value_to_local_cpp_value(idl_type, extended_attributes, v8_value, variable_name=None, needs_type_check=True, index=None, declare_variable=True, isolate='info.GetIsolate()', used_in_private_script=False, return_promise=False):
+# FIXME: this function should be refactored, as this takes too many flags.
+def v8_value_to_local_cpp_value(idl_type, extended_attributes, v8_value, variable_name=None, needs_type_check=True, index=None, declare_variable=True, isolate='info.GetIsolate()', used_in_private_script=False, return_promise=False, needs_exception_state_for_string=False):
     """Returns an expression that converts a V8 value to a C++ value and stores it as a local value."""
 
     # FIXME: Support union type.
     if idl_type.is_union_type:
         return '/* no V8 -> C++ conversion for IDL union type: %s */' % idl_type.name
 
     this_cpp_type = idl_type.cpp_type_args(extended_attributes=extended_attributes, raw_type=True)
     idl_type = idl_type.preprocessed_type
 
     if idl_type.base_type in ('void', 'object', 'EventHandler', 'EventListener'):
         return '/* no V8 -> C++ conversion for IDL type: %s */' % idl_type.name
 
     cpp_value = v8_value_to_cpp_value(idl_type, extended_attributes, v8_value, variable_name, needs_type_check, index, isolate)
 
     if idl_type.is_dictionary:
         return 'TONATIVE_VOID_EXCEPTIONSTATE_ARGINTERNAL(%s, exceptionState)' % cpp_value
 
     if idl_type.is_string_type or idl_type.v8_conversion_needs_exception_state:
         # Types that need error handling and use one of a group of (C++) macros
         # to take care of this.
 
         args = [variable_name, cpp_value]
 
         if idl_type.v8_conversion_needs_exception_state:
             macro = 'TONATIVE_DEFAULT_EXCEPTIONSTATE' if used_in_private_script else 'TONATIVE_VOID_EXCEPTIONSTATE'
-        elif return_promise:
+        elif return_promise or needs_exception_state_for_string:
             macro = 'TOSTRING_VOID_EXCEPTIONSTATE'
         else:
             macro = 'TOSTRING_DEFAULT' if used_in_private_script else 'TOSTRING_VOID'
 
         if macro.endswith('_EXCEPTIONSTATE'):
             args.append('exceptionState')
 
         if used_in_private_script:
             args.append('false')
 
@@ skipping 69 matching lines @@
 
 def v8_conversion_type(idl_type, extended_attributes):
     """Returns V8 conversion type, adding any additional includes.
 
     The V8 conversion type is used to select the C++ -> V8 conversion function
     or v8SetReturnValue* function; it can be an idl_type, a cpp_type, or a
     separate name for the type of conversion (e.g., 'DOMWrapper').
     """
     extended_attributes = extended_attributes or {}
 
-    # FIXME: Support union type.
-    if idl_type.is_union_type:
-        return ''
-
-    if idl_type.is_dictionary:
-        return 'IDLDictionary'
+    if idl_type.is_dictionary or idl_type.is_union_type:
+        return 'DictionaryOrUnion'
 
     # Array or sequence types
     native_array_element_type = idl_type.native_array_element_type
     if native_array_element_type:
         if native_array_element_type.is_interface_type:
             add_includes_for_type(native_array_element_type)
         return 'array'
 
     # Simple types
     base_idl_type = idl_type.base_type
@@ skipping 47 matching lines @@
     # and then use general v8SetReturnValue.
     'array': 'v8SetReturnValue(info, {cpp_value})',
     'Date': 'v8SetReturnValue(info, {cpp_value})',
     'EventHandler': 'v8SetReturnValue(info, {cpp_value})',
     'ScriptValue': 'v8SetReturnValue(info, {cpp_value})',
     'SerializedScriptValue': 'v8SetReturnValue(info, {cpp_value})',
     # DOMWrapper
     'DOMWrapperForMainWorld': 'v8SetReturnValueForMainWorld(info, WTF::getPtr({cpp_value}))',
     'DOMWrapperFast': 'v8SetReturnValueFast(info, WTF::getPtr({cpp_value}), {script_wrappable})',
     'DOMWrapperDefault': 'v8SetReturnValue(info, {cpp_value})',
-    'IDLDictionary': 'v8SetReturnValue(info, result)',
+    # Union types or dictionaries
+    'DictionaryOrUnion': 'v8SetReturnValue(info, result)',
 }
 
 
 def v8_set_return_value(idl_type, cpp_value, extended_attributes=None, script_wrappable='', release=False, for_main_world=False):
     """Returns a statement that converts a C++ value to a V8 value and sets it as a return value.
 
     """
     def dom_wrapper_conversion_type():
         if not script_wrappable:
             return 'DOMWrapperDefault'
@@ skipping 11 matching lines @@
         this_v8_conversion_type = dom_wrapper_conversion_type()
 
     format_string = V8_SET_RETURN_VALUE[this_v8_conversion_type]
     # FIXME: oilpan: Remove .release() once we remove all RefPtrs from generated code.
     if release:
         cpp_value = '%s.release()' % cpp_value
     statement = format_string.format(cpp_value=cpp_value, script_wrappable=script_wrappable)
     return statement
 
 
-def v8_set_return_value_union(idl_type, cpp_value, extended_attributes=None, script_wrappable='', release=False, for_main_world=False):
-    # FIXME: Need to revisit the design of union support.
-    # http://crbug.com/240176
-    return None
-
-
 IdlTypeBase.v8_set_return_value = v8_set_return_value
-IdlUnionType.v8_set_return_value = v8_set_return_value_union
 
 IdlType.release = property(lambda self: self.is_interface_type)
-IdlUnionType.release = property(
-    lambda self: [member_type.is_interface_type
-                  for member_type in self.member_types])
+IdlUnionType.release = False
 
 
 CPP_VALUE_TO_V8_VALUE = {
     # Built-in types
     'Date': 'v8DateOrNaN({cpp_value}, {isolate})',
     'DOMString': 'v8String({isolate}, {cpp_value})',
     'ByteString': 'v8String({isolate}, {cpp_value})',
     'USVString': 'v8String({isolate}, {cpp_value})',
     'boolean': 'v8Boolean({cpp_value}, {isolate})',
     'int': 'v8::Integer::New({isolate}, {cpp_value})',
     'unsigned': 'v8::Integer::NewFromUnsigned({isolate}, {cpp_value})',
     'float': 'v8::Number::New({isolate}, {cpp_value})',
     'unrestricted float': 'v8::Number::New({isolate}, {cpp_value})',
     'double': 'v8::Number::New({isolate}, {cpp_value})',
     'unrestricted double': 'v8::Number::New({isolate}, {cpp_value})',
     'void': 'v8Undefined()',
     # [TreatReturnedNullStringAs]
     'StringOrNull': '{cpp_value}.isNull() ? v8::Handle<v8::Value>(v8::Null({isolate})) : v8String({isolate}, {cpp_value})',
     'StringOrUndefined': '{cpp_value}.isNull() ? v8Undefined() : v8String({isolate}, {cpp_value})',
     # Special cases
     'EventHandler': '{cpp_value} ? v8::Handle<v8::Value>(V8AbstractEventListener::cast({cpp_value})->getListenerObject(impl->executionContext())) : v8::Handle<v8::Value>(v8::Null({isolate}))',
     'ScriptValue': '{cpp_value}.v8Value()',
     'SerializedScriptValue': '{cpp_value} ? {cpp_value}->deserialize() : v8::Handle<v8::Value>(v8::Null({isolate}))',
     # General
     'array': 'v8Array({cpp_value}, {creation_context}, {isolate})',
     'DOMWrapper': 'toV8({cpp_value}, {creation_context}, {isolate})',
-    'IDLDictionary': 'toV8({cpp_value}, {creation_context}, {isolate})',
+    # Union types or dictionaries
+    'DictionaryOrUnion': 'toV8({cpp_value}, {creation_context}, {isolate})',
 }
 
 
 def cpp_value_to_v8_value(idl_type, cpp_value, isolate='info.GetIsolate()', creation_context='info.Holder()', extended_attributes=None):
     """Returns an expression that converts a C++ value to a V8 value."""
     # the isolate parameter is needed for callback interfaces
     idl_type, cpp_value = preprocess_idl_type_and_value(idl_type, cpp_value, extended_attributes)
     this_v8_conversion_type = idl_type.v8_conversion_type(extended_attributes)
     format_string = CPP_VALUE_TO_V8_VALUE[this_v8_conversion_type]
     statement = format_string.format(cpp_value=cpp_value, isolate=isolate, creation_context=creation_context)
@@ skipping 37 matching lines @@
 
 
 def is_explicit_nullable(idl_type):
     # Nullable type that isn't implicit nullable (see above.) For such types,
     # we use Nullable<T> or similar explicit ways to represent a null value.
     return idl_type.is_nullable and not idl_type.is_implicit_nullable
 
 IdlTypeBase.is_implicit_nullable = property(is_implicit_nullable)
 IdlUnionType.is_implicit_nullable = False
 IdlTypeBase.is_explicit_nullable = property(is_explicit_nullable)