perf(lsp): improve some tsc op hot paths (#13473)

cli/lsp/documents.rs

@@ -724,9 +724,9 @@ impl FileSystemDocuments {
     &mut self,
     cache: &HttpCache,
     maybe_resolver: Option<&dyn deno_graph::source::Resolver>,
-    specifier: ModuleSpecifier,
+    specifier: &ModuleSpecifier,
   ) -> Option<Document> {
-    let path = get_document_path(cache, &specifier)?;
+    let path = get_document_path(cache, specifier)?;
     let fs_version = calculate_fs_version(&path)?;
     let bytes = fs::read(path).ok()?;
     let doc = if specifier.scheme() == "file" {
@@ -741,11 +741,11 @@ impl FileSystemDocuments {
         maybe_resolver,
       )
     } else {
-      let cache_filename = cache.get_cache_filename(&specifier)?;
+      let cache_filename = cache.get_cache_filename(specifier)?;
       let metadata = http_cache::Metadata::read(&cache_filename).ok()?;
       let maybe_content_type = metadata.headers.get("content-type").cloned();
       let maybe_headers = Some(&metadata.headers);
-      let (_, maybe_charset) = map_content_type(&specifier, maybe_content_type);
+      let (_, maybe_charset) = map_content_type(specifier, maybe_content_type);
       let content = Arc::new(get_source_from_bytes(bytes, maybe_charset).ok()?);
       Document::new(
         specifier.clone(),
@@ -756,7 +756,7 @@ impl FileSystemDocuments {
       )
     };
     self.dirty = true;
-    self.docs.insert(specifier, doc)
+    self.docs.insert(specifier.clone(), doc)
   }
 }
 
@@ -949,6 +949,22 @@ impl Documents {
     }
   }
 
+  /// Used by the tsc op_exists to shortcut trying to load a document to provide
+  /// information to CLI without allocating a document.
+  pub(crate) fn exists(&self, specifier: &ModuleSpecifier) -> bool {
+    let specifier = self.specifier_resolver.resolve(specifier);
+    if let Some(specifier) = specifier {
+      if self.open_docs.contains_key(&specifier) {
+        return true;
+      }
+      if let Some(path) = get_document_path(&self.cache, &specifier) {
+        return path.is_file();
+      }
+    }
+
+    false
+  }
+
   /// Return a document for the specifier.
   pub fn get(&self, specifier: &ModuleSpecifier) -> Option<Document> {
     let specifier = self.specifier_resolver.resolve(specifier)?;
@@ -969,7 +985,7 @@ impl Documents {
         file_system_docs.refresh_document(
           &self.cache,
           self.get_maybe_resolver(),
-          specifier.clone(),
+          &specifier,
         );
       }
       file_system_docs.docs.get(&specifier).cloned()

cli/lsp/performance.rs

@@ -83,7 +83,7 @@ impl Default for Performance {
   fn default() -> Self {
     Self {
       counts: Default::default(),
-      max_size: 1_000,
+      max_size: 3_000,
       measures: Default::default(),
     }
   }

cli/lsp/tsc.rs

@@ -2373,13 +2373,13 @@ struct SpecifierArgs {
 }
 
 fn op_exists(state: &mut State, args: SpecifierArgs) -> Result<bool, AnyError> {
-  let mark = state.performance.mark("op_exists", Some(&args));
+  // we don't measure the performance of op_exists anymore because as of TS 4.5
+  // it is noisy with all the checking for custom libs, that we can't see the
+  // forrest for the trees as well as it compounds any lsp performance
+  // challenges, opening a single document in the editor causes some 3k worth
+  // of op_exists requests... :omg:
   let specifier = state.normalize_specifier(args.specifier)?;
-  let result = state
-    .state_snapshot
-    .documents
-    .contains_specifier(&specifier);
-  state.performance.measure(mark);
+  let result = state.state_snapshot.documents.exists(&specifier);
   Ok(result)
 }
 
@@ -2564,9 +2564,10 @@ fn op_script_version(
   state: &mut State,
   args: ScriptVersionArgs,
 ) -> Result<Option<String>, AnyError> {
-  let mark = state.performance.mark("op_script_version", Some(&args));
+  // this op is very "noisy" and measuring its performance is not useful, so we
+  // don't measure it uniquely anymore.
   let specifier = state.normalize_specifier(args.specifier)?;
-  let r = if specifier.scheme() == "asset" {
+  if specifier.scheme() == "asset" {
     if state.state_snapshot.assets.contains_key(&specifier) {
       Ok(Some("1".to_string()))
     } else {
@@ -2579,10 +2580,7 @@ fn op_script_version(
       .get(&specifier)
       .map(|d| d.script_version());
     Ok(script_version)
-  };
-
-  state.performance.measure(mark);
-  r
+  }
 }
 
 /// Create and setup a JsRuntime based on a snapshot. It is expected that the