Mojo C++ bindings: switch union to use the new serialization interface.

mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl

 {#  TODO(yzshen): Make these templates more readable. #}
 
 {#  Computes the serialized size for the specified struct.
     |struct| is the struct definition.
     |input_field_pattern| should be a pattern that contains one string
     placeholder, for example, "input->%s", "p_%s". The placeholder will be
     substituted with struct field names to refer to the input fields.
     |context| is the name of the serialization context.
     |input_may_be_temp| indicates whether any input may be temporary obejcts.
     We need to assign temporary objects to local variables before passing it to
@@ skipping 11 matching lines @@
 {%-   for pf in struct.packed.packed_fields_in_ordinal_order if pf.field.kind|is_object_kind %}
 {%-     set name = pf.field.name -%}
 {%-     set kind = pf.field.kind -%}
 {%-     set original_input_field = input_field_pattern|format(name) %}
 {%-     set input_field = "in_%s"|format(name) if input_may_be_temp
                                                else original_input_field %}
 {%-     if input_may_be_temp %}
   decltype({{original_input_field}}) in_{{name}} = {{original_input_field}};
 {%-     endif %}
 
-{%-     if kind|is_struct_kind or kind|is_string_kind or kind|is_array_kind or
-           kind|is_map_kind %}
-{%-       set serializer_type = kind|unmapped_type_for_serializer %}
+{%-     set serializer_type = kind|unmapped_type_for_serializer %}
+{%-     if kind|is_union_kind %}
+  size += mojo::internal::PrepareToSerialize<{{serializer_type}}>(
+      {{input_field}}, true, {{context}});
+{%-     else %}
   size += mojo::internal::PrepareToSerialize<{{serializer_type}}>(
       {{input_field}}, {{context}});
-{%-     elif kind|is_union_kind %}
-  size += GetSerializedSize_({{input_field}}, true, {{context}});
-{%-     else %}
-  size += GetSerializedSize_({{input_field}}, {{context}});
 {%-     endif %}
 {%-   endfor %}
 {%- endmacro -%}
 
 {#  Serializes the specified struct.
     |struct| is the struct definition.
     |struct_display_name| is the display name for the struct that can be showed
     in error/log messages, for example, "FooStruct", "FooMethod request".
     |input_field_pattern| should be a pattern that contains one string
     placeholder, for example, "input->%s", "p_%s". The placeholder will be
@@ skipping 21 matching lines @@
 {%-     set input_field = "in_%s"|format(name) if input_may_be_temp
                                                else original_input_field %}
 {%-     if input_may_be_temp %}
   decltype({{original_input_field}}) in_{{name}} = {{original_input_field}};
 {%-     endif %}
 
 {%-     if kind|is_array_kind or kind|is_map_kind %}
   const mojo::internal::ArrayValidateParams {{name}}_validate_params(
       {{kind|get_array_validate_params_ctor_args|indent(10)}});
   mojo::internal::Serialize<{{serializer_type}}>(
-          {{input_field}}, {{buffer}}, &{{output}}->{{name}}.ptr,
-          &{{name}}_validate_params, {{context}});
-{%-     elif kind|is_struct_kind or kind|is_string_kind %}
+      {{input_field}}, {{buffer}}, &{{output}}->{{name}}.ptr,
+      &{{name}}_validate_params, {{context}});
+{%-     elif kind|is_union_kind %}
+  auto {{name}}_ptr = &{{output}}->{{name}};
+  mojo::internal::Serialize<{{serializer_type}}>(
+      {{input_field}}, {{buffer}}, &{{name}}_ptr, true, {{context}});
+{%-     else %}
   mojo::internal::Serialize<{{serializer_type}}>(
       {{input_field}}, {{buffer}}, &{{output}}->{{name}}.ptr, {{context}});
-{%-     elif kind|is_union_kind %}
-  auto {{name}}_ptr = &{{output}}->{{name}};
-  SerializeUnion_(std::move({{input_field}}), {{buffer}}, &{{name}}_ptr, true,
-                  {{context}});
-{%-     else %}
-  Serialize_(std::move({{input_field}}), {{buffer}}, &{{output}}->{{name}}.ptr,
-             {{context}});
 {%-     endif %}
 {%-     if not kind|is_nullable_kind %}
   MOJO_INTERNAL_DLOG_SERIALIZATION_WARNING(
 {%-       if kind|is_union_kind %}
       {{output}}->{{name}}.is_null(),
 {%-       else %}
       !{{output}}->{{name}}.ptr,
 {%-       endif %}
       mojo::internal::VALIDATION_ERROR_UNEXPECTED_NULL_POINTER,
       "null {{name}} in {{struct_display_name}}");
@@ skipping 58 matching lines @@
 {%-   set last_checked_version = 0 %}
 {%-   for pf in struct.packed.packed_fields_in_ordinal_order %}
 {%-     set output_field = output_field_pattern|format(pf.field.name) %}
 {%-     set name = pf.field.name %}
 {%-     set kind = pf.field.kind %}
 {%-     if pf.min_version > last_checked_version %}
 {%-       set last_checked_version = pf.min_version %}
     if ({{input}}->header_.version < {{pf.min_version}})
       break;
 {%-     endif %}
-{%-     if kind|is_struct_kind or kind|is_string_kind or kind|is_array_kind or
-           kind|is_map_kind %}
-{%-       set serializer_type = kind|unmapped_type_for_serializer %}
+{%-     set serializer_type = kind|unmapped_type_for_serializer %}
+{%-     if kind|is_union_kind %}
+    if (!mojo::internal::Deserialize<{{serializer_type}}>(
+            &{{input}}->{{name}}, &{{output_field}}, {{context}})) {
+      {{success}} = false;
+    }
+{%-     elif kind|is_object_kind %}
     if (!mojo::internal::Deserialize<{{serializer_type}}>(
             {{input}}->{{name}}.ptr, &{{output_field}}, {{context}})) {
       {{success}} = false;
     }
-{%-     elif kind|is_union_kind %}
-    if (!Deserialize_(&{{input}}->{{name}}, &{{output_field}}, {{context}}))
-      {{success}} = false;
-{%-     elif kind|is_object_kind %}
-    if (!Deserialize_({{input}}->{{name}}.ptr, &{{output_field}}, {{context}}))
-      {{success}} = false;
 {%-     elif kind|is_interface_kind %}
     mojo::internal::InterfaceDataToPointer(
         &{{input}}->{{name}}, &{{output_field}}, {{context}});
 {%-     elif kind|is_interface_request_kind %}
     {{output_field}}.Bind(
         ({{context}})->handles.TakeHandleAs<mojo::MessagePipeHandle>(
             {{input}}->{{name}}));
 {%-     elif kind|is_any_handle_kind %}
     {{output_field}} = ({{context}})->handles.TakeHandleAs<
         typename decltype({{output_field}})::RawHandleType>(
             {{input}}->{{name}});
 {%-   elif kind|is_associated_interface_kind %}
     mojo::internal::AssociatedInterfaceDataToPtrInfo(&{{input}}->{{name}}, &{{output_field}}, ({{context}})->router.get());
 {%-   elif kind|is_associated_interface_request_kind %}
     mojo::internal::AssociatedInterfaceRequestHelper::SetHandle(
         &{{output_field}},
         ({{context}})->router->CreateLocalEndpointHandle(mojo::internal::FetchAndReset(&{{input}}->{{name}})));
 {%-     elif kind|is_enum_kind %}
     {{output_field}} = static_cast<{{kind|get_qualified_name_for_kind}}>({{input}}->{{name}});
 {%-     else %}
     {{output_field}} = {{input}}->{{name}};
 {%-     endif %}
 {%-   endfor %}
   } while (false);
 {%- endmacro %}