EXPECT_EQ(std::string("Function 'MyFunc' has no attr named 'foo_attr'."),
            std::string(TF_Message(s_)));
  TF_DeleteBuffer(attr_buf);

  // Set attr
  tensorflow::AttrValue attr;
  attr.set_s("test_attr_value");
  std::string bytes;
  attr.SerializeToString(&bytes);
  TF_FunctionSetAttrValueProto(func_, "test_attr_name", bytes.data(),
                               bytes.size(), s_);