WIP bindings: Expand usage of NativeValueTraits.

third_party/WebKit/Source/bindings/scripts/v8_types.py

Index: third_party/WebKit/Source/bindings/scripts/v8_types.py
diff --git a/third_party/WebKit/Source/bindings/scripts/v8_types.py b/third_party/WebKit/Source/bindings/scripts/v8_types.py
index 1b50fee8e9186d4baacf5ef73debb492495f08b8..2c0b58d8e1802e6d678e7f39b1784ce247ade0e8 100644
--- a/third_party/WebKit/Source/bindings/scripts/v8_types.py
+++ b/third_party/WebKit/Source/bindings/scripts/v8_types.py
@@ -145,15 +145,6 @@ def cpp_type(idl_type, extended_attributes=None, raw_type=False, used_as_rvalue_
             bool, True if the C++ type is used as an element of a container.
             Containers can be an array, a sequence or a dictionary.
     """
-    def string_mode():
-        if idl_type.is_nullable:
-            return 'TreatNullAndUndefinedAsNullString'
-        if extended_attributes.get('TreatNullAs') == 'EmptyString':
-            return 'TreatNullAsEmptyString'
-        if extended_attributes.get('TreatNullAs') == 'NullString':
-            return 'TreatNullAsNullString'
-        return ''
-
     extended_attributes = extended_attributes or {}
     idl_type = idl_type.preprocessed_type
 
@@ -186,7 +177,7 @@ def cpp_type(idl_type, extended_attributes=None, raw_type=False, used_as_rvalue_
     if idl_type.is_string_type:
         if not raw_type:
             return 'String'
-        return 'V8StringResource<%s>' % string_mode()
+        return 'V8StringResource<>'
 
     if base_idl_type == 'ArrayBufferView' and 'FlexibleArrayBufferView' in extended_attributes:
         return 'FlexibleArrayBufferView'
@@ -374,7 +365,7 @@ def includes_for_type(idl_type, extended_attributes=None):
             set(['bindings/%s/v8/V8%s.h' % (component_dir[base_idl_type], base_idl_type)])
         )
     if idl_type.is_basic_type:
-        return set()
+        return set(['bindings/core/v8/IDLTypes.h'])
     if base_idl_type.endswith('ConstructorConstructor'):
         # FIXME: rename to NamedConstructor
         # FIXME: replace with a [NamedConstructorAttribute] extended attribute
@@ -393,7 +384,8 @@ def includes_for_type(idl_type, extended_attributes=None):
     if base_idl_type not in component_dir:
         return set()
     return set(['bindings/%s/v8/V8%s.h' % (component_dir[base_idl_type],
-                                           base_idl_type)])
+                                           base_idl_type),
+                'bindings/core/v8/IDLTypes.h'])
 
 IdlType.includes_for_type = includes_for_type
 
@@ -484,32 +476,9 @@ def set_component_dirs(new_component_dirs):
 ################################################################################
 
 V8_VALUE_TO_CPP_VALUE = {
-    # Basic
-    'Date': 'toCoreDate({isolate}, {v8_value}, exceptionState)',
-    'DOMString': '{v8_value}',
-    'ByteString': 'toByteString({isolate}, {arguments})',
-    'USVString': 'toUSVString({isolate}, {arguments})',
-    'boolean': 'toBoolean({isolate}, {arguments})',
-    'float': 'toRestrictedFloat({isolate}, {arguments})',
-    'unrestricted float': 'toFloat({isolate}, {arguments})',
-    'double': 'toRestrictedDouble({isolate}, {arguments})',
-    'unrestricted double': 'toDouble({isolate}, {arguments})',
-    'byte': 'toInt8({isolate}, {arguments})',
-    'octet': 'toUInt8({isolate}, {arguments})',
-    'short': 'toInt16({isolate}, {arguments})',
-    'unsigned short': 'toUInt16({isolate}, {arguments})',
-    'long': 'toInt32({isolate}, {arguments})',
-    'unsigned long': 'toUInt32({isolate}, {arguments})',
-    'long long': 'toInt64({isolate}, {arguments})',
-    'unsigned long long': 'toUInt64({isolate}, {arguments})',
     # Interface types
-    'Dictionary': 'Dictionary({isolate}, {v8_value}, exceptionState)',
     'FlexibleArrayBufferView': 'toFlexibleArrayBufferView({isolate}, {v8_value}, {variable_name}, allocateFlexibleArrayBufferViewStorage({v8_value}))',
     'NodeFilter': 'toNodeFilter({v8_value}, info.Holder(), ScriptState::current({isolate}))',
-    'Promise': 'ScriptPromise::cast(ScriptState::current({isolate}), {v8_value})',
-    'SerializedScriptValue': 'SerializedScriptValue::serialize({isolate}, {v8_value}, nullptr, nullptr, exceptionState)',
-    'ScriptValue': 'ScriptValue(ScriptState::current({isolate}), {v8_value})',
-    'Window': 'toDOMWindow({isolate}, {v8_value})',
     'XPathNSResolver': 'toXPathNSResolver(ScriptState::current({isolate}), {v8_value})',
 }
 
@@ -518,6 +487,7 @@ def v8_conversion_needs_exception_state(idl_type):
     return (idl_type.is_numeric_type or
             idl_type.is_enum or
             idl_type.is_dictionary or
+            idl_type.is_string_type or
             idl_type.name in ('Boolean', 'ByteString', 'Date', 'Dictionary', 'USVString', 'SerializedScriptValue'))
 
 IdlType.v8_conversion_needs_exception_state = property(v8_conversion_needs_exception_state)
@@ -545,18 +515,38 @@ def v8_conversion_is_trivial(idl_type):
 IdlType.v8_conversion_is_trivial = property(v8_conversion_is_trivial)
 
 
+def idl_type_name(idl_type):
+    idl_type = idl_type.preprocessed_type
+    if idl_type.native_array_element_type:
+        return 'idl::Sequence<%s>' % idl_type_name(idl_type.native_array_element_type)
+    elif idl_type.is_union_type:
+        return idl_type.as_union_type.name
+    elif idl_type.is_basic_type:
+        return 'idl::%s' % idl_type.name
+    elif idl_type.implemented_as is not None:
+        return idl_type.implemented_as
+    return idl_type.name
+
+
 def v8_value_to_cpp_value(idl_type, extended_attributes, v8_value, variable_name, index, isolate):
     if idl_type.name == 'void':
         return ''
 
-    # Array or sequence types
-    native_array_element_type = idl_type.native_array_element_type
-    if native_array_element_type:
-        return v8_value_to_cpp_value_array_or_sequence(native_array_element_type, v8_value, index, isolate)
+    def string_mode(idl_type):
+        if idl_type.is_nullable:
+            return 'TreatNullAndUndefinedAsNullString'
+        if extended_attributes.get('TreatNullAs') == 'EmptyString':
+            return 'TreatNullAsEmptyString'
+        if extended_attributes.get('TreatNullAs') == 'NullString':
+            return 'TreatNullAsNullString'
+        return 'DefaultMode'
 
     # Simple types
     idl_type = idl_type.preprocessed_type
-    base_idl_type = idl_type.as_union_type.name if idl_type.is_union_type else idl_type.base_type
+    if idl_type.is_union_type:
+        base_idl_type = idl_type.as_union_type.name
+    else:
+        base_idl_type = idl_type.base_type
 
     if 'FlexibleArrayBufferView' in extended_attributes:
         if base_idl_type not in TYPED_ARRAY_TYPES.union(set(['ArrayBufferView'])):
@@ -569,53 +559,36 @@ def v8_value_to_cpp_value(idl_type, extended_attributes, v8_value, variable_name
             configuration = 'EnforceRange'
         elif 'Clamp' in extended_attributes:
             configuration = 'Clamp'
-        arguments = ', '.join([v8_value, configuration, 'exceptionState'])
-    elif idl_type.v8_conversion_needs_exception_state:
-        arguments = ', '.join([v8_value, 'exceptionState'])
+        arguments = ', '.join([v8_value, 'exceptionState', configuration])
+    elif idl_type.native_array_element_type:
+        # Index is None for setters, index (starting at 0) for method arguments,
+        # and is used to provide a human-readable exception message
+        if index is None:
+            index = 0  # special case, meaning "setter"
+        else:
+            index += 1  # human-readable index
+        arguments = ', '.join([v8_value, 'exceptionState', str(index)])
     else:
-        arguments = v8_value
+        arguments = ', '.join([v8_value, 'exceptionState'])
+
     if base_idl_type in V8_VALUE_TO_CPP_VALUE:
         cpp_expression_format = V8_VALUE_TO_CPP_VALUE[base_idl_type]
-    elif idl_type.is_array_buffer_or_view:
-        cpp_expression_format = (
-            '{v8_value}->Is{idl_type}() ? '
-            'V8{idl_type}::toImpl(v8::Local<v8::{idl_type}>::Cast({v8_value})) : 0')
-    elif idl_type.is_union_type:
-        nullable = 'UnionTypeConversionMode::Nullable' if idl_type.includes_nullable_type else 'UnionTypeConversionMode::NotNullable'
-        cpp_expression_format = 'V8{idl_type}::toImpl({isolate}, {v8_value}, {variable_name}, %s, exceptionState)' % nullable
-    elif idl_type.use_output_parameter_for_result:
-        cpp_expression_format = 'V8{idl_type}::toImpl({isolate}, {v8_value}, {variable_name}, exceptionState)'
-    elif idl_type.is_callback_function:
-        cpp_expression_format = (
-            '{idl_type}::create(ScriptState::current({isolate}), {v8_value})')
     else:
-        cpp_expression_format = (
-            'V8{idl_type}::toImplWithTypeCheck({isolate}, {v8_value})')
-
-    return cpp_expression_format.format(arguments=arguments, idl_type=base_idl_type, v8_value=v8_value, variable_name=variable_name, isolate=isolate)
+        str_mode = string_mode(idl_type)
 
+        if idl_type.is_nullable:
+            idl_type = idl_type.inner_type
+        base_idl_type = idl_type_name(idl_type)
 
-def v8_value_to_cpp_value_array_or_sequence(native_array_element_type, v8_value, index, isolate='info.GetIsolate()'):
-    # Index is None for setters, index (starting at 0) for method arguments,
-    # and is used to provide a human-readable exception message
-    if index is None:
-        index = 0  # special case, meaning "setter"
-    else:
-        index += 1  # human-readable index
-    if (native_array_element_type.is_interface_type and
-        native_array_element_type.name != 'Dictionary'):
-        this_cpp_type = None
-        expression_format = 'toMemberNativeArray<{native_array_element_type}>({v8_value}, {index}, {isolate}, exceptionState)'
-    else:
-        this_cpp_type = native_array_element_type.cpp_type
-        if native_array_element_type.is_dictionary or native_array_element_type.is_union_type:
-            vector_type = 'HeapVector'
+        if base_idl_type == 'idl::String':
+            nvt_args = '<%s>' % str_mode
         else:
-            vector_type = 'Vector'
-        expression_format = 'toImplArray<%s<{cpp_type}>>({v8_value}, {index}, {isolate}, exceptionState)' % vector_type
-    expression = expression_format.format(native_array_element_type=native_array_element_type.name, cpp_type=this_cpp_type,
-                                          index=index, v8_value=v8_value, isolate=isolate)
-    return expression
+            nvt_args = ''
+
+        cpp_expression_format = (
+            'NativeValueTraits<{idl_type}>::nativeValue%s({isolate}, {arguments})' % nvt_args)
+
+    return cpp_expression_format.format(arguments=arguments, idl_type=base_idl_type, v8_value=v8_value, variable_name=variable_name, isolate=isolate)
 
 
 # FIXME: this function should be refactored, as this takes too many flags.
@@ -638,24 +611,10 @@ def v8_value_to_local_cpp_value(idl_type, extended_attributes, v8_value, variabl
     # meaningful if 'check_expression' is not None.
     return_expression = bailout_return_value
 
-    if idl_type.is_string_type or idl_type.v8_conversion_needs_exception_state:
+    if idl_type.v8_conversion_needs_exception_state:
         # Types for which conversion can fail and that need error handling.
-
         check_expression = 'exceptionState.hadException()'
-
-        if idl_type.is_dictionary or idl_type.is_union_type:
-            set_expression = cpp_value
-        else:
-            assign_expression = cpp_value
-            # Note: 'not idl_type.v8_conversion_needs_exception_state' implies
-            # 'idl_type.is_string_type', but there are types for which both are
-            # true (ByteString and USVString), so using idl_type.is_string_type
-            # as the condition here would be wrong.
-            if not idl_type.v8_conversion_needs_exception_state:
-                if use_exception_state:
-                    check_expression = '!%s.prepare(exceptionState)' % variable_name
-                else:
-                    check_expression = '!%s.prepare()' % variable_name
+        assign_expression = cpp_value
     elif not idl_type.v8_conversion_is_trivial and not idl_type.is_callback_function:
         return {
             'error_message': 'no V8 -> C++ conversion for IDL type: %s' % idl_type.name