message: [lang] Add an initial POC empty contract input test
diff: @@ -59,4 +59,9 @@ fn contract_gen_impl2(input: proc_macro2::TokenStream) -> Result<proc_macro2::To
  let tokens = gen::codegen(&hir_contract);
  Ok(tokens.into())
  }
  +
  +#[test]
  +fn empty_contract_input() {
  + use quote::quote;
  + assert!(contract_gen_impl2(quote!{}).is_err());
  }
  