implement Error for BodyLimitExceeded

actix-http/src/body/utils.rs

@@ -3,6 +3,7 @@ use std::task::Poll;
 use actix_rt::pin;
 use actix_utils::future::poll_fn;
 use bytes::{Bytes, BytesMut};
+use derive_more::{Display, Error};
 use futures_core::ready;
 
 use super::{BodySize, MessageBody};
@@ -36,7 +37,8 @@ pub async fn to_bytes<B: MessageBody>(body: B) -> Result<Bytes, B::Error> {
 }
 
 /// Error type returned from [`to_bytes_limited`] when body produced exceeds limit.
-#[derive(Debug)]
+#[derive(Debug, Display, Error)]
+#[display(fmt = "limit exceeded while collecting body bytes")]
 #[non_exhaustive]
 pub struct BodyLimitExceeded;