message: [lang] Fix a bug that codegen for deploy handlers with no arguments failed
diff: @@ -82,8 +82,13 @@ fn codegen_for_instantiate(tokens: &mut TokenStream, contract: &hir::Contract) {
  }
  deploy_call_args
  };
  + let deploy_fn_args_toks = if deploy_fn_args.iter().count() > 0 {
  + deploy_fn_args.into_token_stream()
  + } else {
  + quote! {()}
  + };
  quote! {
  - .on_deploy(|env, #deploy_fn_args| {
  + .on_deploy(|env, #deploy_fn_args_toks| {
  let (handler, state) = env.split_mut();
  state.deploy(handler, #deploy_call_args)
  })
  