refactor(ast): Change AST parsing error to return struct with message and location (#10911)

* Remove unused check js emit option.
* Improve parse error.
* Format.

cli/ast.rs

@@ -11,23 +11,16 @@ use std::error::Error;
 use std::fmt;
 use std::ops::Range;
 use std::rc::Rc;
-use std::sync::Arc;
-use std::sync::Mutex;
 use swc_common::chain;
 use swc_common::comments::Comment;
 use swc_common::comments::CommentKind;
 use swc_common::comments::SingleThreadedComments;
-use swc_common::errors::Diagnostic;
-use swc_common::errors::DiagnosticBuilder;
-use swc_common::errors::Emitter;
-use swc_common::errors::Handler;
-use swc_common::errors::HandlerFlags;
 use swc_common::FileName;
 use swc_common::Globals;
-use swc_common::Loc;
 use swc_common::SourceFile;
 use swc_common::SourceMap;
 use swc_common::Span;
+use swc_common::Spanned;
 use swc_ecmascript::ast::Module;
 use swc_ecmascript::ast::Program;
 use swc_ecmascript::codegen::text_writer::JsWriter;
@@ -89,57 +82,18 @@ impl std::fmt::Display for Location {
   }
 }
 
-/// A buffer for collecting diagnostic messages from the AST parser.
+/// A diagnostic from the AST parser.
-#[derive(Debug)]
+#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct DiagnosticBuffer(Vec<String>);
+pub struct Diagnostic {
+  pub location: Location,
+  pub message: String,
+}
 
-impl Error for DiagnosticBuffer {}
+impl Error for Diagnostic {}
 
-impl fmt::Display for DiagnosticBuffer {
+impl fmt::Display for Diagnostic {
   fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    let s = self.0.join(",");
+    write!(f, "{} at {}", self.message, self.location)
-    f.pad(&s)
-  }
-}
-
-impl DiagnosticBuffer {
-  pub fn from_error_buffer<F>(error_buffer: ErrorBuffer, get_loc: F) -> Self
-  where
-    F: Fn(Span) -> Loc,
-  {
-    let s = error_buffer.0.lock().unwrap().clone();
-    let diagnostics = s
-      .iter()
-      .map(|d| {
-        let mut msg = d.message();
-
-        if let Some(span) = d.span.primary_span() {
-          let loc = get_loc(span);
-          let file_name = match &loc.file.name {
-            FileName::Custom(n) => n,
-            _ => unreachable!(),
-          };
-          msg = format!(
-            "{} at {}:{}:{}",
-            msg, file_name, loc.line, loc.col_display
-          );
-        }
-
-        msg
-      })
-      .collect::<Vec<String>>();
-
-    Self(diagnostics)
-  }
-}
-
-/// A buffer for collecting errors from the AST parser.
-#[derive(Debug, Clone, Default)]
-pub struct ErrorBuffer(Arc<Mutex<Vec<Diagnostic>>>);
-
-impl Emitter for ErrorBuffer {
-  fn emit(&mut self, db: &DiagnosticBuilder) {
-    self.0.lock().unwrap().push((**db).clone());
   }
 }
 
@@ -192,9 +146,6 @@ pub enum ImportsNotUsedAsValues {
 /// Options which can be adjusted when transpiling a module.
 #[derive(Debug, Clone)]
 pub struct EmitOptions {
-  /// Indicate if JavaScript is being checked/transformed as well, or if it is
-  /// only TypeScript.
-  pub check_js: bool,
   /// When emitting a legacy decorator, also emit experimental decorator meta
   /// data.  Defaults to `false`.
   pub emit_metadata: bool,
@@ -221,7 +172,6 @@ pub struct EmitOptions {
 impl Default for EmitOptions {
   fn default() -> Self {
     EmitOptions {
-      check_js: false,
       emit_metadata: false,
       imports_not_used_as_values: ImportsNotUsedAsValues::Remove,
       inline_source_map: true,
@@ -244,7 +194,6 @@ impl From<config_file::TsConfig> for EmitOptions {
         _ => ImportsNotUsedAsValues::Remove,
       };
     EmitOptions {
-      check_js: options.check_js,
       emit_metadata: options.emit_decorator_metadata,
       imports_not_used_as_values,
       inline_source_map: options.inline_source_map,
@@ -424,31 +373,17 @@ pub fn parse_with_source_map(
     FileName::Custom(specifier.to_string()),
     source.to_string(),
   );
-  let error_buffer = ErrorBuffer::default();
   let syntax = get_syntax(media_type);
   let input = StringInput::from(&*source_file);
   let comments = SingleThreadedComments::default();
 
-  let handler = Handler::with_emitter_and_flags(
-    Box::new(error_buffer.clone()),
-    HandlerFlags {
-      can_emit_warnings: true,
-      dont_buffer_diagnostics: true,
-      ..HandlerFlags::default()
-    },
-  );
-
   let lexer = Lexer::new(syntax, TARGET, input, Some(&comments));
   let mut parser = swc_ecmascript::parser::Parser::new_from(lexer);
 
   let sm = &source_map;
-  let module = parser.parse_module().map_err(move |err| {
+  let module = parser.parse_module().map_err(move |err| Diagnostic {
-    let mut diagnostic = err.into_diagnostic(&handler);
+    location: sm.lookup_char_pos(err.span().lo).into(),
-    diagnostic.emit();
+    message: err.into_kind().msg().to_string(),
-
-    DiagnosticBuffer::from_error_buffer(error_buffer, |span| {
-      sm.lookup_char_pos(span.lo)
-    })
   })?;
   let leading_comments =
     comments.with_leading(module.span.lo, |comments| comments.to_vec());

cli/errors.rs

@@ -9,7 +9,7 @@
 //!   Diagnostics are compile-time type errors, whereas JsErrors are runtime
 //!   exceptions.
 
-use crate::ast::DiagnosticBuffer;
+use crate::ast::Diagnostic;
 use crate::import_map::ImportMapError;
 use deno_core::error::AnyError;
 
@@ -17,7 +17,7 @@ fn get_import_map_error_class(_: &ImportMapError) -> &'static str {
   "URIError"
 }
 
-fn get_diagnostic_class(_: &DiagnosticBuffer) -> &'static str {
+fn get_diagnostic_class(_: &Diagnostic) -> &'static str {
   "SyntaxError"
 }
 
@@ -27,10 +27,7 @@ pub(crate) fn get_error_class_name(e: &AnyError) -> &'static str {
       e.downcast_ref::<ImportMapError>()
         .map(get_import_map_error_class)
     })
-    .or_else(|| {
+    .or_else(|| e.downcast_ref::<Diagnostic>().map(get_diagnostic_class))
-      e.downcast_ref::<DiagnosticBuffer>()
-        .map(get_diagnostic_class)
-    })
     .unwrap_or_else(|| {
       panic!(
         "Error '{}' contains boxed error of unknown type:{}",

cli/module_graph.rs

@@ -1102,10 +1102,11 @@ impl Graph {
           }
         }
         BundleType::None => {
+          let check_js = config.get_check_js();
           let emit_options: ast::EmitOptions = config.into();
           for (_, module_slot) in self.modules.iter_mut() {
             if let ModuleSlot::Module(module) = module_slot {
-              if !(emit_options.check_js
+              if !(check_js
                 || module.media_type == MediaType::Jsx
                 || module.media_type == MediaType::Tsx
                 || module.media_type == MediaType::TypeScript)
@@ -1669,6 +1670,7 @@ impl Graph {
       .merge_tsconfig_from_config_file(options.maybe_config_file.as_ref())?;
 
     let config = ts_config.as_bytes();
+    let check_js = ts_config.get_check_js();
     let emit_options: ast::EmitOptions = ts_config.into();
     let mut emit_count = 0_u32;
     for (_, module_slot) in self.modules.iter_mut() {
@@ -1683,7 +1685,7 @@ impl Graph {
         }
         // if we don't have check_js enabled, we won't touch non TypeScript or JSX
         // modules
-        if !(emit_options.check_js
+        if !(check_js
           || module.media_type == MediaType::Jsx
           || module.media_type == MediaType::Tsx
           || module.media_type == MediaType::TypeScript)