perf(ast/estree): skip escaping identifiers

crates/oxc_ast/src/ast/js.rs

@@ -209,6 +209,7 @@ pub use match_expression;
 #[estree(rename = "Identifier")]
 pub struct IdentifierName<'a> {
     pub span: Span,
+    #[estree(json_safe)]
     pub name: Atom<'a>,
 }
 
@@ -224,6 +225,7 @@ pub struct IdentifierName<'a> {
 pub struct IdentifierReference<'a> {
     pub span: Span,
     /// The name of the identifier being referenced.
+    #[estree(json_safe)]
     pub name: Atom<'a>,
     /// Reference ID
     ///
@@ -246,6 +248,7 @@ pub struct IdentifierReference<'a> {
 pub struct BindingIdentifier<'a> {
     pub span: Span,
     /// The identifier name being bound.
+    #[estree(json_safe)]
     pub name: Atom<'a>,
     /// Unique identifier for this binding.
     ///
@@ -267,6 +270,7 @@ pub struct BindingIdentifier<'a> {
 #[estree(rename = "Identifier")]
 pub struct LabelIdentifier<'a> {
     pub span: Span,
+    #[estree(json_safe)]
     pub name: Atom<'a>,
 }
 

crates/oxc_ast/src/ast/jsx.rs

@@ -430,6 +430,7 @@ pub struct JSXIdentifier<'a> {
     /// Node location in source code
     pub span: Span,
     /// The name of the identifier.
+    #[estree(json_safe)]
     pub name: Atom<'a>,
 }
 

crates/oxc_ast/src/ast/ts.rs

@@ -1029,6 +1029,7 @@ pub struct TSConstructSignatureDeclaration<'a> {
 #[estree(rename = "Identifier")]
 pub struct TSIndexSignatureName<'a> {
     pub span: Span,
+    #[estree(json_safe)]
     pub name: Atom<'a>,
     pub type_annotation: Box<'a, TSTypeAnnotation<'a>>,
 }

crates/oxc_ast/src/generated/derive_estree.rs

@@ -84,7 +84,7 @@ impl ESTree for IdentifierName<'_> {
         state.serialize_field("type", &JsonSafeString("Identifier"));
         state.serialize_field("start", &self.span.start);
         state.serialize_field("end", &self.span.end);
-        state.serialize_field("name", &self.name);
+        state.serialize_field("name", &JsonSafeString(self.name.as_str()));
         state.end();
     }
 }
@@ -95,7 +95,7 @@ impl ESTree for IdentifierReference<'_> {
         state.serialize_field("type", &JsonSafeString("Identifier"));
         state.serialize_field("start", &self.span.start);
         state.serialize_field("end", &self.span.end);
-        state.serialize_field("name", &self.name);
+        state.serialize_field("name", &JsonSafeString(self.name.as_str()));
         state.end();
     }
 }
@@ -106,7 +106,7 @@ impl ESTree for BindingIdentifier<'_> {
         state.serialize_field("type", &JsonSafeString("Identifier"));
         state.serialize_field("start", &self.span.start);
         state.serialize_field("end", &self.span.end);
-        state.serialize_field("name", &self.name);
+        state.serialize_field("name", &JsonSafeString(self.name.as_str()));
         state.end();
     }
 }
@@ -117,7 +117,7 @@ impl ESTree for LabelIdentifier<'_> {
         state.serialize_field("type", &JsonSafeString("Identifier"));
         state.serialize_field("start", &self.span.start);
         state.serialize_field("end", &self.span.end);
-        state.serialize_field("name", &self.name);
+        state.serialize_field("name", &JsonSafeString(self.name.as_str()));
         state.end();
     }
 }
@@ -2156,7 +2156,7 @@ impl ESTree for JSXIdentifier<'_> {
         state.serialize_field("type", &JsonSafeString("JSXIdentifier"));
         state.serialize_field("start", &self.span.start);
         state.serialize_field("end", &self.span.end);
-        state.serialize_field("name", &self.name);
+        state.serialize_field("name", &JsonSafeString(self.name.as_str()));
         state.end();
     }
 }
@@ -2879,7 +2879,7 @@ impl ESTree for TSIndexSignatureName<'_> {
         state.serialize_field("type", &JsonSafeString("Identifier"));
         state.serialize_field("start", &self.span.start);
         state.serialize_field("end", &self.span.end);
-        state.serialize_field("name", &self.name);
+        state.serialize_field("name", &JsonSafeString(self.name.as_str()));
         state.serialize_field("typeAnnotation", &self.type_annotation);
         state.end();
     }

tasks/ast_tools/src/derives/estree.rs

@@ -140,6 +140,7 @@ fn parse_estree_attr(location: AttrLocation, part: AttrPart) -> Result<()> {
         AttrLocation::StructField(struct_def, field_index) => match part {
             AttrPart::Tag("skip") => struct_def.fields[field_index].estree.skip = true,
             AttrPart::Tag("flatten") => struct_def.fields[field_index].estree.flatten = true,
+            AttrPart::Tag("json_safe") => struct_def.fields[field_index].estree.json_safe = true,
             AttrPart::String("rename", value) => {
                 struct_def.fields[field_index].estree.rename = Some(value);
             }
@@ -372,6 +373,17 @@ impl<'s> StructSerializerGenerator<'s> {
             quote! {
                 #wrapper_ident { array: &#self_path.#field_name_ident, after: &#self_path.#append_from_ident  }
             }
+        } else if field.estree.json_safe {
+            // Wrap value in `JsonSafeString(...)` if field is tagged `#[estree(json_safe)]`
+            match field.type_def(self.schema).name() {
+                "&str" => quote!( JsonSafeString(#self_path.#field_name_ident) ),
+                "Atom" => quote!( JsonSafeString(#self_path.#field_name_ident.as_str()) ),
+                _ => panic!(
+                    "`#[estree(json_safe)]` is only valid on struct fields containing a `&str` or `Atom`: {}::{}",
+                    struct_def.name(),
+                    field.name(),
+                ),
+            }
         } else {
             quote!( #self_path.#field_name_ident )
         };

tasks/ast_tools/src/schema/extensions/estree.rs

@@ -56,6 +56,8 @@ pub struct ESTreeStructField {
     pub append_field_index: Option<usize>,
     pub skip: bool,
     pub flatten: bool,
+    // `true` for fields containing a `&str` or `Atom` which does not need escaping in JSON
+    pub json_safe: bool,
     pub is_ts: bool,
 }