fix(lsp): fix deadlocks, use one big mutex (#9271)

The LSP code had numerous places where competing threads could take out
out locks in different orders, making it very prone to deadlocks.
This commit sidesteps the entire issue by switching to a single lock.

The above is a little white lie: the Sources struct still uses a mutex
internally to avoid having to boil the ocean (because being honest about
what it does involves changing all its methods to `&mut self` but that
ripples out extensively...) I'll save that one for another day.

1 files changed, 5 insertions, 13 deletions

diff --git a/cli/lsp/tsc.rs b/cli/lsp/tsc.rs
index 8c7c4189c..0ba08fdfa 100644
--- a/cli/lsp/tsc.rs
+++ b/cli/lsp/tsc.rs
@@ -96,7 +96,7 @@ pub struct AssetDocument {
 pub async fn get_asset(
   specifier: &ModuleSpecifier,
   ts_server: &TsServer,
-  state_snapshot: &StateSnapshot,
+  state_snapshot: &mut StateSnapshot,
 ) -> Result<Option<AssetDocument>, AnyError> {
   let specifier_str = specifier.to_string().replace("asset:///", "");
   if let Some(text) = tsc::get_asset(&specifier_str) {
@@ -106,8 +106,6 @@ pub async fn get_asset(
     });
     state_snapshot
       .assets
-      .lock()
-      .unwrap()
       .insert(specifier.clone(), maybe_asset.clone());
     Ok(maybe_asset)
   } else {
@@ -128,8 +126,6 @@ pub async fn get_asset(
     };
     state_snapshot
       .assets
-      .lock()
-      .unwrap()
       .insert(specifier.clone(), maybe_asset.clone());
     Ok(maybe_asset)
   }
@@ -915,7 +911,7 @@ fn get_length(state: &mut State, args: Value) -> Result<Value, AnyError> {
       .unwrap();
     Ok(json!(content.encode_utf16().count()))
   } else {
-    let mut sources = state.state_snapshot.sources.lock().unwrap();
+    let sources = &state.state_snapshot.sources;
     Ok(json!(sources.get_length_utf16(&specifier).unwrap()))
   }
 }
@@ -940,7 +936,7 @@ fn get_text(state: &mut State, args: Value) -> Result<Value, AnyError> {
       .unwrap()
       .clone()
   } else {
-    let mut sources = state.state_snapshot.sources.lock().unwrap();
+    let sources = &state.state_snapshot.sources;
     sources.get_text(&specifier).unwrap()
   };
   Ok(json!(text::slice(&content, v.start..v.end)))
@@ -950,11 +946,7 @@ fn resolve(state: &mut State, args: Value) -> Result<Value, AnyError> {
   let v: ResolveArgs = serde_json::from_value(args)?;
   let mut resolved = Vec::<Option<(String, String)>>::new();
   let referrer = ModuleSpecifier::resolve_url(&v.base)?;
-  let mut sources = if let Ok(sources) = state.state_snapshot.sources.lock() {
-    sources
-  } else {
-    return Err(custom_error("Deadlock", "deadlock locking sources"));
-  };
+  let sources = &state.state_snapshot.sources;
 
   if state.state_snapshot.documents.contains(&referrer) {
     if let Some(dependencies) =
@@ -1048,7 +1040,7 @@ fn script_version(state: &mut State, args: Value) -> Result<Value, AnyError> {
   if let Some(version) = state.state_snapshot.documents.version(&specifier) {
     return Ok(json!(version.to_string()));
   } else {
-    let mut sources = state.state_snapshot.sources.lock().unwrap();
+    let sources = &state.state_snapshot.sources;
     if let Some(version) = sources.get_script_version(&specifier) {
       return Ok(json!(version));
     }