Mojo C++ bindings: inline struct data view field getters.

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

Index: mojo/public/tools/bindings/generators/cpp_templates/struct_data_view_declaration.tmpl
diff --git a/mojo/public/tools/bindings/generators/cpp_templates/struct_data_view_declaration.tmpl b/mojo/public/tools/bindings/generators/cpp_templates/struct_data_view_declaration.tmpl
index 7ba07147ba79bb3b33b5f00355c8e5b41656a42b..575a331769a8c2078b2490b93b99b9023505d602 100644
--- a/mojo/public/tools/bindings/generators/cpp_templates/struct_data_view_declaration.tmpl
+++ b/mojo/public/tools/bindings/generators/cpp_templates/struct_data_view_declaration.tmpl
@@ -4,33 +4,48 @@ class {{struct.name}}DataView {
 
   {{struct.name}}DataView(
       internal::{{struct.name}}_Data* data,
-      mojo::internal::SerializationContext* context);
+      mojo::internal::SerializationContext* context)
+{%- if struct|requires_context_for_data_view %}
+      : data_(data), context_(context) {}
+{%- else %}
+      : data_(data) {}
+{%- endif %}
 
   bool is_null() const { return !data_; }
 
 {%- for pf in struct.packed.packed_fields_in_ordinal_order %}
 {%-   set kind = pf.field.kind %}
 {%-   set name = pf.field.name %}
-{%-   if kind|is_object_kind %}
+{%-   if kind|is_union_kind %}
   void Get{{name|under_to_camel}}DataView(
       {{kind|cpp_data_view_type}}* output);
 
-{%-     if kind|is_union_kind %}
-  bool Read{{name|under_to_camel}}({{kind|cpp_wrapper_type}}* output);
-
+  bool Read{{name|under_to_camel}}({{kind|cpp_wrapper_type}}* output) {
+{%-     if pf.min_version != 0 %}
+    auto pointer = data_->header_.version >= {{pf.min_version}}
+                   ? &data_->{{name}} : nullptr;
 {%-     else %}
+    auto pointer = &data_->{{name}};
+{%-     endif %}
+    return mojo::internal::Deserialize<{{kind|unmapped_type_for_serializer}}>(
+        pointer, output, context_);
+}
+
+{%-   elif kind|is_object_kind %}
+  void Get{{name|under_to_camel}}DataView(
+      {{kind|cpp_data_view_type}}* output);
+
   template <typename UserType>
   bool Read{{name|under_to_camel}}(UserType* output) {
-{%-       if pf.min_version != 0 %}
+{%-     if pf.min_version != 0 %}
     auto pointer = data_->header_.version >= {{pf.min_version}}
                    ? data_->{{name}}.Get() : nullptr;
-{%-       else %}
+{%-     else %}
     auto pointer = data_->{{name}}.Get();
-{%-       endif %}
+{%-     endif %}
     return mojo::internal::Deserialize<{{kind|unmapped_type_for_serializer}}>(
         pointer, output, context_);
   }
-{%-     endif %}
 
 {%-   elif kind|is_enum_kind %}
   template <typename UserType>
@@ -45,17 +60,43 @@ class {{struct.name}}DataView {
         data_value, output);
   }
 
-  {{kind|get_qualified_name_for_kind}} {{name}}() const;
+  {{kind|get_qualified_name_for_kind}} {{name}}() const {
+{%-     if pf.min_version != 0 %}
+    if (data_->header_.version < {{pf.min_version}})
+      return {{kind|get_qualified_name_for_kind}}{};
+{%-     endif %}
+    return static_cast<{{kind|get_qualified_name_for_kind}}>(data_->{{name}});
+  }
 
 {%-   elif kind|is_any_handle_or_interface_kind %}
-  {{kind|cpp_wrapper_type}} Take{{name|under_to_camel}}();
+  {{kind|cpp_wrapper_type}} Take{{name|under_to_camel}}() {
+    {{kind|cpp_wrapper_type}} result;
+{%-     if pf.min_version != 0 %}
+    if (data_->header_.version < {{pf.min_version}})
+      return result;
+{%-     endif %}
+    bool ret =
+        mojo::internal::Deserialize<{{kind|unmapped_type_for_serializer}}>(
+            &data_->{{name}}, &result, context_);
+    DCHECK(ret);
+    return result;
+  }
 
 {%-   else %}
-  {{kind|cpp_wrapper_type}} {{name}}() const;
+  {{kind|cpp_wrapper_type}} {{name}}() const {
+{%-     if pf.min_version != 0 %}
+    if (data_->header_.version < {{pf.min_version}})
+      return {{kind|cpp_wrapper_type}}{};
+{%-     endif %}
+    return data_->{{name}};
+  }
+
 {%-   endif %}
 {%- endfor %}
  private:
   internal::{{struct.name}}_Data* data_ = nullptr;
+{%- if struct|requires_context_for_data_view %}
   mojo::internal::SerializationContext* context_ = nullptr;
+{%- endif %}
 };