Replace ConnectionError in public API with io::Error

CHANGELOG.md

@@ -1,3 +1,9 @@
+# 0.11.0
+
+- Remove `ConnectionError` from public API in favor `std::io::Error`. See [PR 135].
+
+[PR 135]: https://github.com/libp2p/rust-yamux/pull/135
+
 # 0.10.1
 
 - Update `parking_lot` dependency. See [PR 126].

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "yamux"
-version = "0.10.1"
+version = "0.11.0"
 authors = ["Parity Technologies <[email protected]>"]
 license = "Apache-2.0 OR MIT"
 description = "Multiplexer over reliable, ordered connections"

src/connection/control.rs

@@ -9,19 +9,19 @@
 // at https://opensource.org/licenses/MIT.
 
 use super::ControlCommand;
-use crate::{error::ConnectionError, Stream};
+use crate::error::{into_io_error, ConnectionError};
+use crate::Stream;
 use futures::{
     channel::{mpsc, oneshot},
     prelude::*,
     ready,
 };
 use std::{
+    io,
     pin::Pin,
     task::{Context, Poll},
 };
 
-type Result<T> = std::result::Result<T, ConnectionError>;
-
 /// The Yamux `Connection` controller.
 ///
 /// While a Yamux connection makes progress via its `next_stream` method,
@@ -36,7 +36,7 @@ pub struct Control {
     /// Command channel to `Connection`.
     sender: mpsc::Sender<ControlCommand>,
     /// Pending state of `poll_open_stream`.
-    pending_open: Option<oneshot::Receiver<Result<Stream>>>,
+    pending_open: Option<oneshot::Receiver<Result<Stream, ConnectionError>>>,
     /// Pending state of `poll_close`.
     pending_close: Option<oneshot::Receiver<()>>,
 }
@@ -61,14 +61,19 @@ impl Control {
     }
 
     /// Open a new stream to the remote.
-    pub async fn open_stream(&mut self) -> Result<Stream> {
+    pub async fn open_stream(&mut self) -> io::Result<Stream> {
         let (tx, rx) = oneshot::channel();
-        self.sender.send(ControlCommand::OpenStream(tx)).await?;
-        rx.await?
+        self.sender
+            .send(ControlCommand::OpenStream(tx))
+            .await
+            .map_err(into_io_error)?;
+        let stream = rx.await.map_err(into_io_error)?.map_err(into_io_error)?;
+
+        Ok(stream)
     }
 
     /// Close the connection.
-    pub async fn close(&mut self) -> Result<()> {
+    pub async fn close(&mut self) -> io::Result<()> {
         let (tx, rx) = oneshot::channel();
         if self
             .sender
@@ -86,17 +91,22 @@ impl Control {
     }
 
     /// [`Poll`] based alternative to [`Control::open_stream`].
-    pub fn poll_open_stream(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<Stream>> {
+    pub fn poll_open_stream(
+        mut self: Pin<&mut Self>,
+        cx: &mut Context,
+    ) -> Poll<io::Result<Stream>> {
         loop {
             match self.pending_open.take() {
                 None => {
-                    ready!(self.sender.poll_ready(cx)?);
+                    ready!(self.sender.poll_ready(cx).map_err(into_io_error)?);
                     let (tx, rx) = oneshot::channel();
-                    self.sender.start_send(ControlCommand::OpenStream(tx))?;
+                    self.sender
+                        .start_send(ControlCommand::OpenStream(tx))
+                        .map_err(into_io_error)?;
                     self.pending_open = Some(rx)
                 }
-                Some(mut rx) => match rx.poll_unpin(cx)? {
-                    Poll::Ready(result) => return Poll::Ready(result),
+                Some(mut rx) => match rx.poll_unpin(cx).map_err(into_io_error)? {
+                    Poll::Ready(result) => return Poll::Ready(result.map_err(into_io_error)),
                     Poll::Pending => {
                         self.pending_open = Some(rx);
                         return Poll::Pending;
@@ -112,7 +122,7 @@ impl Control {
     }
 
     /// [`Poll`] based alternative to [`Control::close`].
-    pub fn poll_close(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<()>> {
+    pub fn poll_close(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<io::Result<()>> {
         loop {
             match self.pending_close.take() {
                 None => {

src/error.rs

@@ -9,6 +9,7 @@
 // at https://opensource.org/licenses/MIT.
 
 use crate::frame::FrameDecodeError;
+use std::io;
 
 /// The various error cases a connection may encounter.
 #[non_exhaustive]
@@ -63,6 +64,15 @@ impl std::error::Error for ConnectionError {
     }
 }
 
+pub fn into_io_error<E: Into<ConnectionError>>(error: E) -> std::io::Error {
+    let connection_error = error.into();
+
+    match connection_error {
+        ConnectionError::Io(io) => io,
+        other => io::Error::new(io::ErrorKind::Other, other),
+    }
+}
+
 impl From<std::io::Error> for ConnectionError {
     fn from(e: std::io::Error) -> Self {
         ConnectionError::Io(e)

src/lib.rs

@@ -35,7 +35,6 @@ mod tests;
 pub(crate) mod connection;
 
 pub use crate::connection::{into_stream, Connection, Control, Mode, Packet, Stream};
-pub use crate::error::ConnectionError;
 pub use crate::frame::{
     header::{HeaderDecodeError, StreamId},
     FrameDecodeError,

src/tests.rs

@@ -9,7 +9,7 @@
 // at https://opensource.org/licenses/MIT.
 
 use crate::WindowUpdateMode;
-use crate::{connection::State, Config, Connection, ConnectionError, Control, Mode};
+use crate::{connection::State, error::ConnectionError, Config, Connection, Control, Mode};
 use futures::channel::mpsc::{unbounded, UnboundedReceiver, UnboundedSender};
 use futures::executor::LocalPool;
 use futures::future::join;
@@ -164,7 +164,12 @@ fn prop_max_streams() {
             for _ in 0..max_streams {
                 v.push(control.open_stream().await.expect("open_stream"))
             }
-            if let Err(ConnectionError::TooManyStreams) = control.open_stream().await {
+            if let Err(Some(Ok(ConnectionError::TooManyStreams))) =
+                control.open_stream().await.map_err(|e| {
+                    e.into_inner()
+                        .map(|inner| inner.downcast::<ConnectionError>().map(|b| *b))
+                })
+            {
                 true
             } else {
                 false

tests/concurrent.rs

@@ -11,6 +11,7 @@
 use futures::{channel::mpsc, prelude::*};
 use quickcheck::{Arbitrary, Gen, QuickCheck};
 use std::{
+    io,
     net::{Ipv4Addr, SocketAddr, SocketAddrV4},
     sync::Arc,
 };
@@ -106,7 +107,7 @@ async fn roundtrip(
             log::debug!("C: {}: read {} bytes", stream.id(), frame.len());
             assert_eq!(&data[..], &frame[..]);
             tx.unbounded_send(1).expect("unbounded_send");
-            Ok::<(), yamux::ConnectionError>(())
+            Ok::<(), io::Error>(())
         });
     }
     let n = rx