message: das.tests: check partial serialization
diff: @@ -20,6 +20,7 @@ namespace symbol
  using elle::das::operator <<;
  +/// A struct without ctor.
  struct DevicePOD
  {
  bool
  @@ -30,6 +31,7 @@ struct DevicePOD
  int id;
  std::string name;
  + int useless_and_not_serialized;
  using Model
  = elle::das::Model<DevicePOD,
  @@ -56,6 +58,7 @@ struct NopeString
  operator =(NopeString const&) = delete;
  };
  +/// A struct with a ctor.
  struct Device
  {
  Device(int id, NopeString name)
  @@ -71,6 +74,7 @@ struct Device
  int id;
  NopeString name;
  + int useless_and_not_serialized;
  using Model = elle::das::Model<Device,
  decltype(elle::meta::list(symbol::id,
  