class Google::Protobuf::Descriptor

fields.
names e.g. `dup` or `class` which are perfectly valid for proto
self.setup_accessors! in order to avoid conflicts with bad field
Accessor for field by name. Does not delegate to methods setup by

def index_internal(name)
  field_descriptor = self.class.descriptor.lookup(name)
  get_field field_descriptor unless field_descriptor.nil?
end