10 files changed, 45 insertions, 12 deletions

diff --git a/crates/ra_cargo_watch/Cargo.toml b/crates/ra_cargo_watch/Cargo.toml
index 9ead48abf..dd814fc9d 100644
--- a/crates/ra_cargo_watch/Cargo.toml
+++ b/crates/ra_cargo_watch/Cargo.toml
@@ -6,12 +6,13 @@ authors = ["rust-analyzer developers"]
 
 [dependencies]
 crossbeam-channel = "0.4"
-lsp-types = { version = "0.69.0", features = ["proposed"] }
+lsp-types = { version = "0.70.0", features = ["proposed"] }
 log = "0.4.3"
 cargo_metadata = "0.9.1"
 jod-thread = "0.1.0"
 parking_lot = "0.10.0"
+serde_json = "1.0.45"
 
 [dev-dependencies]
-insta = "0.12.0"
+insta = "0.13.0"
 serde_json = "1.0"
\ No newline at end of file
diff --git a/crates/ra_cargo_watch/src/conv.rs b/crates/ra_cargo_watch/src/conv.rs
index ac0f1d28a..8fba400ae 100644
--- a/crates/ra_cargo_watch/src/conv.rs
+++ b/crates/ra_cargo_watch/src/conv.rs
@@ -117,7 +117,7 @@ fn is_deprecated(rd: &RustDiagnostic) -> bool {
     }
 }
 
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct SuggestedFix {
     pub title: String,
     pub location: Location,
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_clippy_pass_by_ref.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_clippy_pass_by_ref.snap
index cb0920914..cb0920914 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_clippy_pass_by_ref.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_clippy_pass_by_ref.snap
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_handles_macro_location.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_handles_macro_location.snap
index 19510ecc1..19510ecc1 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_handles_macro_location.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_handles_macro_location.snap
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_macro_compiler_error.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_macro_compiler_error.snap
index 92f7eec05..92f7eec05 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_macro_compiler_error.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_macro_compiler_error.snap
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_incompatible_type_for_trait.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_incompatible_type_for_trait.snap
index cf683e4b6..cf683e4b6 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_incompatible_type_for_trait.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_incompatible_type_for_trait.snap
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_mismatched_type.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_mismatched_type.snap
index 8c1483c74..8c1483c74 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_mismatched_type.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_mismatched_type.snap
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_unused_variable.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_unused_variable.snap
index eb5a2247b..eb5a2247b 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_unused_variable.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_unused_variable.snap
diff --git a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_wrong_number_of_parameters.snap b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_wrong_number_of_parameters.snap
index 2f4518931..2f4518931 100644
--- a/crates/ra_cargo_watch/src/conv/snapshots/test__snap_rustc_wrong_number_of_parameters.snap
+++ b/crates/ra_cargo_watch/src/conv/snapshots/ra_cargo_watch__conv__test__snap_rustc_wrong_number_of_parameters.snap
diff --git a/crates/ra_cargo_watch/src/lib.rs b/crates/ra_cargo_watch/src/lib.rs
index 7f4c9280c..ea7ddc86b 100644
--- a/crates/ra_cargo_watch/src/lib.rs
+++ b/crates/ra_cargo_watch/src/lib.rs
@@ -7,9 +7,9 @@ use lsp_types::{
     Diagnostic, Url, WorkDoneProgress, WorkDoneProgressBegin, WorkDoneProgressEnd,
     WorkDoneProgressReport,
 };
-use parking_lot::RwLock;
 use std::{
     collections::HashMap,
+    io::{BufRead, BufReader},
     path::PathBuf,
     process::{Command, Stdio},
     sync::Arc,
@@ -38,7 +38,7 @@ pub struct CheckOptions {
 #[derive(Debug)]
 pub struct CheckWatcher {
     pub task_recv: Receiver<CheckTask>,
-    pub state: Arc<RwLock<CheckState>>,
+    pub state: Arc<CheckState>,
     cmd_send: Option<Sender<CheckCommand>>,
     handle: Option<JoinHandle<()>>,
 }
@@ -46,7 +46,7 @@ pub struct CheckWatcher {
 impl CheckWatcher {
     pub fn new(options: &CheckOptions, workspace_root: PathBuf) -> CheckWatcher {
         let options = options.clone();
-        let state = Arc::new(RwLock::new(CheckState::new()));
+        let state = Arc::new(CheckState::new());
 
         let (task_send, task_recv) = unbounded::<CheckTask>();
         let (cmd_send, cmd_recv) = unbounded::<CheckCommand>();
@@ -59,7 +59,7 @@ impl CheckWatcher {
 
     /// Returns a CheckWatcher that doesn't actually do anything
     pub fn dummy() -> CheckWatcher {
-        let state = Arc::new(RwLock::new(CheckState::new()));
+        let state = Arc::new(CheckState::new());
         CheckWatcher { task_recv: never(), cmd_send: None, handle: None, state }
     }
 
@@ -87,7 +87,7 @@ impl std::ops::Drop for CheckWatcher {
     }
 }
 
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct CheckState {
     diagnostic_collection: HashMap<Url, Vec<Diagnostic>>,
     suggested_fix_collection: HashMap<Url, Vec<SuggestedFix>>,
@@ -216,8 +216,10 @@ impl CheckWatcherThread {
                 self.last_update_req.take();
                 task_send.send(CheckTask::ClearDiagnostics).unwrap();
 
-                // By replacing the watcher, we drop the previous one which
-                // causes it to shut down automatically.
+                // Replace with a dummy watcher first so we drop the original and wait for completion
+                std::mem::replace(&mut self.watcher, WatchThread::dummy());
+
+                // Then create the actual new watcher
                 self.watcher = WatchThread::new(&self.options, &self.workspace_root);
             }
         }
@@ -348,15 +350,45 @@ impl WatchThread {
             // which will break out of the loop, and continue the shutdown
             let _ = message_send.send(CheckEvent::Begin);
 
-            for message in cargo_metadata::parse_messages(command.stdout.take().unwrap()) {
+            // We manually read a line at a time, instead of using serde's
+            // stream deserializers, because the deserializer cannot recover
+            // from an error, resulting in it getting stuck, because we try to
+            // be resillient against failures.
+            //
+            // Because cargo only outputs one JSON object per line, we can
+            // simply skip a line if it doesn't parse, which just ignores any
+            // erroneus output.
+            let stdout = BufReader::new(command.stdout.take().unwrap());
+            for line in stdout.lines() {
+                let line = match line {
+                    Ok(line) => line,
+                    Err(err) => {
+                        log::error!("Couldn't read line from cargo: {}", err);
+                        continue;
+                    }
+                };
+
+                let message = serde_json::from_str::<cargo_metadata::Message>(&line);
                 let message = match message {
                     Ok(message) => message,
                     Err(err) => {
-                        log::error!("Invalid json from cargo check, ignoring: {}", err);
+                        log::error!(
+                            "Invalid json from cargo check, ignoring ({}): {:?} ",
+                            err,
+                            line
+                        );
                         continue;
                     }
                 };
 
+                // Skip certain kinds of messages to only spend time on what's useful
+                match &message {
+                    Message::CompilerArtifact(artifact) if artifact.fresh => continue,
+                    Message::BuildScriptExecuted(_) => continue,
+                    Message::Unknown => continue,
+                    _ => {}
+                }
+
                 match message_send.send(CheckEvent::Msg(message)) {
                     Ok(()) => {}
                     Err(_err) => {