3 files changed, 16 insertions, 19 deletions

diff --git a/crates/gen_lsp_server/src/lib.rs b/crates/gen_lsp_server/src/lib.rs
index 1cd5a3a7c..7ecef83cb 100644
--- a/crates/gen_lsp_server/src/lib.rs
+++ b/crates/gen_lsp_server/src/lib.rs
@@ -5,11 +5,12 @@
 //! Run with `RUST_LOG=gen_lsp_server=debug` to see all the messages.
 //!
 //! ```no_run
+//! use std::error::Error;
 //! use crossbeam_channel::{Sender, Receiver};
 //! use lsp_types::{ServerCapabilities, InitializeParams, request::{GotoDefinition, GotoDefinitionResponse}};
 //! use gen_lsp_server::{run_server, stdio_transport, handle_shutdown, RawMessage, RawResponse};
 //!
-//! fn main() -> Result<(), failure::Error> {
+//! fn main() -> Result<(), Box<dyn Error + Send + Sync>> {
 //!     let (receiver, sender, io_threads) = stdio_transport();
 //!     run_server(
 //!         ServerCapabilities::default(),
@@ -25,7 +26,7 @@
 //!     _params: InitializeParams,
 //!     receiver: &Receiver<RawMessage>,
 //!     sender: &Sender<RawMessage>,
-//! ) -> Result<(), failure::Error> {
+//! ) -> Result<(), Box<dyn Error + Send + Sync>> {
 //!     for msg in receiver {
 //!         match msg {
 //!             RawMessage::Request(req) => {
@@ -54,7 +55,7 @@
 //! }
 //! ```
 
-use failure::{bail, format_err};
+use std::error::Error;
 
 mod msg;
 mod stdio;
@@ -66,7 +67,7 @@ use lsp_types::{
     InitializeParams, InitializeResult, ServerCapabilities,
 };
 
-pub type Result<T> = ::std::result::Result<T, failure::Error>;
+pub type Result<T> = std::result::Result<T, Box<dyn Error + Send + Sync>>;
 pub use crate::{
     msg::{ErrorCode, RawMessage, RawNotification, RawRequest, RawResponse, RawResponseError},
     stdio::{stdio_transport, Threads},
@@ -92,8 +93,8 @@ pub fn run_server(
     match receiver.recv() {
         Ok(RawMessage::Notification(n)) => n
             .cast::<Exit>()
-            .map_err(|n| format_err!("unexpected notification during shutdown: {:?}", n))?,
-        m => bail!("unexpected message during shutdown: {:?}", m),
+            .map_err(|n| format!("unexpected notification during shutdown: {:?}", n))?,
+        m => Err(format!("unexpected message during shutdown: {:?}", m))?,
     }
     log::info!("lsp server shutdown complete");
     Ok(())
@@ -118,19 +119,18 @@ fn initialize(
 ) -> Result<InitializeParams> {
     let (id, params) = match receiver.recv() {
         Ok(RawMessage::Request(req)) => match req.cast::<Initialize>() {
-            Err(req) => bail!("expected initialize request, got {:?}", req),
+            Err(req) => Err(format!("expected initialize request, got {:?}", req))?,
             Ok(req) => req,
         },
-        msg => bail!("expected initialize request, got {:?}", msg),
+        msg => Err(format!("expected initialize request, got {:?}", msg))?,
     };
     let resp = RawResponse::ok::<Initialize>(id, &InitializeResult { capabilities: caps });
     sender.send(RawMessage::Response(resp)).unwrap();
     match receiver.recv() {
         Ok(RawMessage::Notification(n)) => {
-            n.cast::<Initialized>()
-                .map_err(|_| format_err!("expected initialized notification"))?;
+            n.cast::<Initialized>().map_err(|_| "expected initialized notification")?;
         }
-        _ => bail!("expected initialized notification"),
+        _ => Err(format!("expected initialized notification"))?,
     }
     Ok(params)
 }
diff --git a/crates/gen_lsp_server/src/msg.rs b/crates/gen_lsp_server/src/msg.rs
index 1d39ba4bc..2928e4f8b 100644
--- a/crates/gen_lsp_server/src/msg.rs
+++ b/crates/gen_lsp_server/src/msg.rs
@@ -3,7 +3,6 @@ use std::io::{BufRead, Write};
 use lsp_types::{notification::Notification, request::Request};
 use serde::{Deserialize, Serialize};
 use serde_json::{from_str, from_value, to_string, to_value, Value};
-use failure::{bail, format_err};
 
 use crate::Result;
 
@@ -175,7 +174,7 @@ fn read_msg_text(inp: &mut impl BufRead) -> Result<Option<String>> {
             return Ok(None);
         }
         if !buf.ends_with("\r\n") {
-            bail!("malformed header: {:?}", buf);
+            Err(format!("malformed header: {:?}", buf))?;
         }
         let buf = &buf[..buf.len() - 2];
         if buf.is_empty() {
@@ -183,13 +182,12 @@ fn read_msg_text(inp: &mut impl BufRead) -> Result<Option<String>> {
         }
         let mut parts = buf.splitn(2, ": ");
         let header_name = parts.next().unwrap();
-        let header_value =
-            parts.next().ok_or_else(|| format_err!("malformed header: {:?}", buf))?;
+        let header_value = parts.next().ok_or_else(|| format!("malformed header: {:?}", buf))?;
         if header_name == "Content-Length" {
             size = Some(header_value.parse::<usize>()?);
         }
     }
-    let size = size.ok_or_else(|| format_err!("no Content-Length"))?;
+    let size = size.ok_or("no Content-Length")?;
     let mut buf = buf.into_bytes();
     buf.resize(size, 0);
     inp.read_exact(&mut buf)?;
diff --git a/crates/gen_lsp_server/src/stdio.rs b/crates/gen_lsp_server/src/stdio.rs
index 2d6418400..f8931f2dc 100644
--- a/crates/gen_lsp_server/src/stdio.rs
+++ b/crates/gen_lsp_server/src/stdio.rs
@@ -4,7 +4,6 @@ use std::{
 };
 
 use crossbeam_channel::{bounded, Receiver, Sender};
-use failure::bail;
 use lsp_types::notification::Exit;
 
 use crate::{RawMessage, Result};
@@ -48,11 +47,11 @@ impl Threads {
     pub fn join(self) -> Result<()> {
         match self.reader.join() {
             Ok(r) => r?,
-            Err(_) => bail!("reader panicked"),
+            Err(_) => Err("reader panicked")?,
         }
         match self.writer.join() {
             Ok(r) => r,
-            Err(_) => bail!("writer panicked"),
+            Err(_) => Err("writer panicked")?,
         }
     }
 }