Rename CapacityErrorType to just CapacityError, implement using thiserror

src/error.rs

@@ -52,7 +52,7 @@ pub enum Error {
     /// - When writing: your message is bigger than the configured max message size
     ///   (64MB by default).
     #[error("Space limit exceeded: {0}")]
-    Capacity(CapacityErrorType),
+    Capacity(CapacityError),
     /// Protocol violation.
     #[error("WebSocket protocol error: {0}")]
     Protocol(ProtocolErrorType),
@@ -118,20 +118,23 @@ impl From<http::status::InvalidStatusCode> for Error {
 impl From<httparse::Error> for Error {
     fn from(err: httparse::Error) -> Self {
         match err {
-            httparse::Error::TooManyHeaders => Error::Capacity(CapacityErrorType::TooManyHeaders),
+            httparse::Error::TooManyHeaders => Error::Capacity(CapacityError::TooManyHeaders),
             e => Error::Protocol(ProtocolErrorType::HttparseError(e)),
         }
     }
 }
 
 /// Indicates the specific type/cause of a capacity error.
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
-pub enum CapacityErrorType {
+#[derive(Error, Debug, PartialEq, Eq, Clone, Copy)]
+pub enum CapacityError {
     /// Too many headers provided (see [`httparse::Error::TooManyHeaders`]).
+    #[error("Too many headers")]
     TooManyHeaders,
     /// Received header is too long.
+    #[error("Header too long")]
     HeaderTooLong,
     /// Message is bigger than the maximum allowed size.
+    #[error("Message too long: {size} > {max_size}")]
     MessageTooLong {
         /// The size of the message.
         size: usize,
@@ -139,22 +142,10 @@ pub enum CapacityErrorType {
         max_size: usize,
     },
     /// TCP buffer is full.
+    #[error("Incoming TCP buffer is full")]
     TcpBufferFull,
 }
 
-impl fmt::Display for CapacityErrorType {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            CapacityErrorType::TooManyHeaders => write!(f, "Too many headers"),
-            CapacityErrorType::HeaderTooLong => write!(f, "Header too long"),
-            CapacityErrorType::MessageTooLong { size, max_size } => {
-                write!(f, "Message too long: {} > {}", size, max_size)
-            }
-            CapacityErrorType::TcpBufferFull => write!(f, "Incoming TCP buffer is full"),
-        }
-    }
-}
-
 /// Indicates the specific type/cause of a protocol error.
 #[derive(Debug, PartialEq, Eq, Clone, Copy)]
 pub enum ProtocolErrorType {

src/handshake/machine.rs

@@ -3,7 +3,7 @@ use log::*;
 use std::io::{Cursor, Read, Write};
 
 use crate::{
-    error::{CapacityErrorType, Error, ProtocolErrorType, Result},
+    error::{CapacityError, Error, ProtocolErrorType, Result},
     util::NonBlockingResult,
 };
 use input_buffer::{InputBuffer, MIN_READ};
@@ -46,7 +46,7 @@ impl<Stream: Read + Write> HandshakeMachine<Stream> {
                 let read = buf
                     .prepare_reserve(MIN_READ)
                     .with_limit(usize::max_value()) // TODO limit size
-                    .map_err(|_| Error::Capacity(CapacityErrorType::HeaderTooLong))?
+                    .map_err(|_| Error::Capacity(CapacityError::HeaderTooLong))?
                     .read_from(&mut self.stream)
                     .no_block()?;
                 match read {

src/protocol/frame/mod.rs

@@ -8,7 +8,7 @@ mod mask;
 
 pub use self::frame::{CloseFrame, Frame, FrameHeader};
 
-use crate::error::{CapacityErrorType, Error, Result};
+use crate::error::{CapacityError, Error, Result};
 use input_buffer::{InputBuffer, MIN_READ};
 use log::*;
 use std::io::{Error as IoError, ErrorKind as IoErrorKind, Read, Write};
@@ -133,7 +133,7 @@ impl FrameCodec {
                     // Enforce frame size limit early and make sure `length`
                     // is not too big (fits into `usize`).
                     if length > max_size as u64 {
-                        return Err(Error::Capacity(CapacityErrorType::MessageTooLong {
+                        return Err(Error::Capacity(CapacityError::MessageTooLong {
                             size: length as usize,
                             max_size,
                         }));
@@ -156,7 +156,7 @@ impl FrameCodec {
                 .in_buffer
                 .prepare_reserve(MIN_READ)
                 .with_limit(usize::max_value())
-                .map_err(|_| Error::Capacity(CapacityErrorType::TcpBufferFull))?
+                .map_err(|_| Error::Capacity(CapacityError::TcpBufferFull))?
                 .read_from(stream)?;
             if size == 0 {
                 trace!("no frame received");
@@ -207,7 +207,7 @@ impl FrameCodec {
 #[cfg(test)]
 mod tests {
 
-    use crate::error::{CapacityErrorType, Error};
+    use crate::error::{CapacityError, Error};
 
     use super::{Frame, FrameSocket};
 
@@ -270,7 +270,7 @@ mod tests {
         let raw = Cursor::new(vec![0x82, 0x07, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07]);
         let mut sock = FrameSocket::new(raw);
         match sock.read_frame(Some(5)) {
-            Err(Error::Capacity(CapacityErrorType::MessageTooLong { size: 7, max_size: 5 })) => {}
+            Err(Error::Capacity(CapacityError::MessageTooLong { size: 7, max_size: 5 })) => {}
             _ => panic!(),
         }
     }

src/protocol/message.rs

@@ -6,7 +6,7 @@ use std::{
 };
 
 use super::frame::CloseFrame;
-use crate::error::{CapacityErrorType, Error, Result};
+use crate::error::{CapacityError, Error, Result};
 
 mod string_collect {
     use utf8::DecodeError;
@@ -122,7 +122,7 @@ impl IncompleteMessage {
         let portion_size = tail.as_ref().len();
         // Be careful about integer overflows here.
         if my_size > max_size || portion_size > max_size - my_size {
-            return Err(Error::Capacity(CapacityErrorType::MessageTooLong {
+            return Err(Error::Capacity(CapacityError::MessageTooLong {
                 size: my_size + portion_size,
                 max_size,
             }));

src/protocol/mod.rs

@@ -669,7 +669,7 @@ impl<T> CheckConnectionReset for Result<T> {
 #[cfg(test)]
 mod tests {
     use super::{Message, Role, WebSocket, WebSocketConfig};
-    use crate::error::{CapacityErrorType, Error};
+    use crate::error::{CapacityError, Error};
 
     use std::{io, io::Cursor};
 
@@ -714,7 +714,7 @@ mod tests {
         let mut socket = WebSocket::from_raw_socket(WriteMoc(incoming), Role::Client, Some(limit));
 
         match socket.read_message() {
-            Err(Error::Capacity(CapacityErrorType::MessageTooLong { size: 13, max_size: 10 })) => {}
+            Err(Error::Capacity(CapacityError::MessageTooLong { size: 13, max_size: 10 })) => {}
             _ => panic!(),
         }
     }
@@ -726,7 +726,7 @@ mod tests {
         let mut socket = WebSocket::from_raw_socket(WriteMoc(incoming), Role::Client, Some(limit));
 
         match socket.read_message() {
-            Err(Error::Capacity(CapacityErrorType::MessageTooLong { size: 3, max_size: 2 })) => {}
+            Err(Error::Capacity(CapacityError::MessageTooLong { size: 3, max_size: 2 })) => {}
             _ => panic!(),
         }
     }