Correctly defuse cancellation on simple requests

src/message.rs

@@ -454,6 +454,8 @@ impl RespEnc {
 		let msg_len = reader.read_u32().await?;
 		let msg = reader.read_exact(msg_len as usize).await?;
 
+		reader.fill_buffer().await;
+
 		Ok(Self {
 			msg,
 			stream: Some(reader.into_stream()),

src/stream.rs

@@ -95,6 +95,26 @@ impl ByteStreamReader {
 	fn try_get(&mut self, read_len: usize) -> Option<Bytes> {
 		self.buf.take_exact(read_len)
 	}
+
+	fn add_stream_next(&mut self, packet: Option<Packet>) {
+		match packet {
+			Some(Ok(slice)) => {
+				self.buf.extend(slice);
+			}
+			Some(Err(e)) => {
+				self.err = Some(e);
+				self.eos = true;
+			}
+			None => {
+				self.eos = true;
+			}
+		}
+	}
+
+	pub async fn fill_buffer(&mut self) {
+		let packet = self.stream.next().await;
+		self.add_stream_next(packet);
+	}
 }
 
 pub enum ReadExactError {
@@ -132,18 +152,8 @@ impl<'a> Future for ByteStreamReadExact<'a> {
 				}
 			}
 
-			match futures::ready!(this.reader.stream.as_mut().poll_next(cx)) {
+			let next_packet = futures::ready!(this.reader.stream.as_mut().poll_next(cx));
-				Some(Ok(slice)) => {
+			this.reader.add_stream_next(next_packet);
-					this.reader.buf.extend(slice);
-				}
-				Some(Err(e)) => {
-					this.reader.err = Some(e);
-					this.reader.eos = true;
-				}
-				None => {
-					this.reader.eos = true;
-				}
-			}
 		}
 	}
 }