Fix onion_message functional_tests `no-std` build

diff --git a/lightning/src/onion_message/functional_tests.rs b/lightning/src/onion_message/functional_tests.rs
index aee7f562defc5915517d696cf032353deee4e3d6..a2f045c3691df5b534121a60c2495c4254a5b415 100644 (file)
--- a/lightning/src/onion_message/functional_tests.rs
+++ b/lightning/src/onion_message/functional_tests.rs
@@ -20,6 +20,7 @@ use bitcoin::network::constants::Network;
 use bitcoin::secp256k1::{PublicKey, Secp256k1};
 
 use crate::io;
+use crate::io_extras::read_to_end;
 use crate::sync::Arc;
 
 struct MessengerNode {
@@ -59,8 +60,7 @@ impl CustomOnionMessageHandler for TestCustomMessageHandler {
        fn handle_custom_message(&self, _msg: Self::CustomMessage) {}
        fn read_custom_message<R: io::Read>(&self, message_type: u64, buffer: &mut R) -> Result<Option<Self::CustomMessage>, DecodeError> where Self: Sized {
                if message_type == CUSTOM_MESSAGE_TYPE {
-                       let mut buf = Vec::new();
-                       buffer.read_to_end(&mut buf)?;
+                       let buf = read_to_end(buffer)?;
                        assert_eq!(buf, CUSTOM_MESSAGE_CONTENTS);
                        return Ok(Some(TestCustomMessage {}))
                }