refactor: use Mutex for ErrorBuffer (#9539)

RwLock should only be used in circumstatnces where it has some benefit.
Multiple concurrent readers is usually an undesirable design bug.

1 files changed, 6 insertions, 12 deletions

diff --git a/cli/ast.rs b/cli/ast.rs
index 156faf972..a8bc5adb4 100644
--- a/cli/ast.rs
+++ b/cli/ast.rs
@@ -12,7 +12,7 @@ use std::fmt;
 use std::ops::Range;
 use std::rc::Rc;
 use std::sync::Arc;
-use std::sync::RwLock;
+use std::sync::Mutex;
 use swc_common::chain;
 use swc_common::comments::Comment;
 use swc_common::comments::CommentKind;
@@ -107,7 +107,7 @@ impl DiagnosticBuffer {
   where
     F: Fn(Span) -> Loc,
   {
-    let s = error_buffer.0.read().unwrap().clone();
+    let s = error_buffer.0.lock().unwrap().clone();
     let diagnostics = s
       .iter()
       .map(|d| {
@@ -134,18 +134,12 @@ impl DiagnosticBuffer {
 }
 
 /// A buffer for collecting errors from the AST parser.
-#[derive(Debug, Clone)]
-pub struct ErrorBuffer(Arc<RwLock<Vec<Diagnostic>>>);
-
-impl ErrorBuffer {
-  pub fn new() -> Self {
-    Self(Arc::new(RwLock::new(Vec::new())))
-  }
-}
+#[derive(Debug, Clone, Default)]
+pub struct ErrorBuffer(Arc<Mutex<Vec<Diagnostic>>>);
 
 impl Emitter for ErrorBuffer {
   fn emit(&mut self, db: &DiagnosticBuilder) {
-    self.0.write().unwrap().push((**db).clone());
+    self.0.lock().unwrap().push((**db).clone());
   }
 }
 
@@ -365,7 +359,7 @@ pub fn parse_with_source_map(
     FileName::Custom(specifier.to_string()),
     source.to_string(),
   );
-  let error_buffer = ErrorBuffer::new();
+  let error_buffer = ErrorBuffer::default();
   let syntax = get_syntax(media_type);
   let input = StringInput::from(&*source_file);
   let comments = SingleThreadedComments::default();