1 files changed, 30 insertions, 28 deletions

diff --git a/cli/lsp/documents.rs b/cli/lsp/documents.rs
index 936d225ec..308e987bd 100644
--- a/cli/lsp/documents.rs
+++ b/cli/lsp/documents.rs
@@ -244,16 +244,18 @@ type MaybeModuleResult =
 type MaybeParsedSourceResult =
   Option<Result<ParsedSource, deno_ast::Diagnostic>>;
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 struct DocumentInner {
-  /// contains the last-known-good set of dependencies from parsing the module
+  /// Contains the last-known-good set of dependencies from parsing the module.
   dependencies: Arc<DocumentDependencies>,
   fs_version: String,
   line_index: Arc<LineIndex>,
   maybe_language_id: Option<LanguageId>,
   maybe_lsp_version: Option<i32>,
   maybe_module: MaybeModuleResult,
-  maybe_navigation_tree: Option<Arc<tsc::NavigationTree>>,
+  // this is a lazily constructed value based on the state of the document,
+  // so having a mutex to hold it is ok
+  maybe_navigation_tree: Mutex<Option<Arc<tsc::NavigationTree>>>,
   maybe_parsed_source: MaybeParsedSourceResult,
   specifier: ModuleSpecifier,
   text_info: SourceTextInfo,
@@ -291,7 +293,7 @@ impl Document {
       maybe_language_id: None,
       maybe_lsp_version: None,
       maybe_module,
-      maybe_navigation_tree: None,
+      maybe_navigation_tree: Mutex::new(None),
       maybe_parsed_source,
       text_info,
       specifier,
@@ -327,7 +329,7 @@ impl Document {
       maybe_language_id: Some(language_id),
       maybe_lsp_version: Some(version),
       maybe_module,
-      maybe_navigation_tree: None,
+      maybe_navigation_tree: Mutex::new(None),
       maybe_parsed_source,
       text_info: source,
       specifier,
@@ -390,27 +392,19 @@ impl Document {
       Arc::new(LineIndex::new(text_info.text_str()))
     };
     Ok(Document(Arc::new(DocumentInner {
+      specifier: self.0.specifier.clone(),
+      fs_version: self.0.fs_version.clone(),
+      maybe_language_id: self.0.maybe_language_id.clone(),
       dependencies,
       text_info,
       line_index,
       maybe_module,
       maybe_parsed_source,
       maybe_lsp_version: Some(version),
-      maybe_navigation_tree: None,
-      ..(*self.0).clone()
+      maybe_navigation_tree: Mutex::new(None),
     })))
   }
 
-  fn with_navigation_tree(
-    &self,
-    navigation_tree: Arc<tsc::NavigationTree>,
-  ) -> Document {
-    Document(Arc::new(DocumentInner {
-      maybe_navigation_tree: Some(navigation_tree),
-      ..(*self.0).clone()
-    }))
-  }
-
   pub fn specifier(&self) -> &ModuleSpecifier {
     &self.0.specifier
   }
@@ -494,7 +488,21 @@ impl Document {
   }
 
   pub fn maybe_navigation_tree(&self) -> Option<Arc<tsc::NavigationTree>> {
-    self.0.maybe_navigation_tree.clone()
+    self.0.maybe_navigation_tree.lock().clone()
+  }
+
+  pub fn update_navigation_tree_if_version(
+    &self,
+    tree: Arc<tsc::NavigationTree>,
+    script_version: &str,
+  ) {
+    // Ensure we are updating the same document that the navigation tree was
+    // created for. Note: this should not be racy between the version check
+    // and setting the navigation tree, because the document is immutable
+    // and this is enforced by it being wrapped in an Arc.
+    if self.script_version() == script_version {
+      *self.0.maybe_navigation_tree.lock() = Some(tree);
+    }
   }
 
   pub fn dependencies(&self) -> &BTreeMap<String, deno_graph::Dependency> {
@@ -1018,23 +1026,17 @@ impl Documents {
   /// Tries to cache a navigation tree that is associated with the provided specifier
   /// if the document stored has the same script version.
   pub fn try_cache_navigation_tree(
-    &mut self,
+    &self,
     specifier: &ModuleSpecifier,
     script_version: &str,
     navigation_tree: Arc<tsc::NavigationTree>,
   ) -> Result<(), AnyError> {
-    if let Some(doc) = self.open_docs.get_mut(specifier) {
-      if doc.script_version() == script_version {
-        *doc = doc.with_navigation_tree(navigation_tree);
-      }
+    if let Some(doc) = self.open_docs.get(specifier) {
+      doc.update_navigation_tree_if_version(navigation_tree, script_version)
     } else {
       let mut file_system_docs = self.file_system_docs.lock();
       if let Some(doc) = file_system_docs.docs.get_mut(specifier) {
-        // ensure we are updating the same document
-        // that the navigation tree was created for
-        if doc.script_version() == script_version {
-          *doc = doc.with_navigation_tree(navigation_tree);
-        }
+        doc.update_navigation_tree_if_version(navigation_tree, script_version);
       } else {
         return Err(custom_error(
           "NotFound",