refactor(ast_codegen): better visit marker parsing. (#4371)

closes #4281

crates/oxc_ast/src/ast/js.rs

@@ -1,6 +1,6 @@
-// NB: `#[span]`, `#[scope(...)]`, `#[visit(...)]`, `#[visit_as(...)]` and `#[visit_args(...)]` do
-// not do anything to the code, They are purely markers for codegen used in
-// `tasts/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in that crate.
+// NB: `#[span]`, `#[scope(...)]` and `#[visit(...)]` do NOT do anything to the code.
+// They are purely markers for codegen used in
+// `tasks/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in those crates.
 
 // Silence erroneous warnings from Rust Analyser for `#[derive(Tsify)]`
 #![allow(non_snake_case)]
@@ -79,7 +79,7 @@ pub enum Expression<'a> {
     ChainExpression(Box<'a, ChainExpression<'a>>) = 16,
     ClassExpression(Box<'a, Class<'a>>) = 17,
     ConditionalExpression(Box<'a, ConditionalExpression<'a>>) = 18,
-    #[visit_args(flags = ScopeFlags::Function)]
+    #[visit(args(flags = ScopeFlags::Function))]
     FunctionExpression(Box<'a, Function<'a>>) = 19,
     ImportExpression(Box<'a, ImportExpression<'a>>) = 20,
     LogicalExpression(Box<'a, LogicalExpression<'a>>) = 21,
@@ -252,7 +252,7 @@ pub enum ArrayExpressionElement<'a> {
     /// <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Trailing_commas#arrays>
     Elision(Elision) = 65,
     // `Expression` variants added here by `inherit_variants!` macro
-    // TODO: support for attributes syntax here so we can use `#[visit_as(ExpressionArrayElement)]`
+    // TODO: support for attributes syntax here so we can use `#[visit(as(ExpressionArrayElement))]`
     @inherit Expression
 }
 }
@@ -966,7 +966,7 @@ pub struct BlockStatement<'a> {
 #[serde(untagged)]
 pub enum Declaration<'a> {
     VariableDeclaration(Box<'a, VariableDeclaration<'a>>) = 32,
-    #[visit_args(flags = ScopeFlags::Function)]
+    #[visit(args(flags = ScopeFlags::Function))]
     FunctionDeclaration(Box<'a, Function<'a>>) = 33,
     ClassDeclaration(Box<'a, Class<'a>>) = 34,
     UsingDeclaration(Box<'a, UsingDeclaration<'a>>) = 35,
@@ -1292,7 +1292,7 @@ pub struct TryStatement<'a> {
     pub span: Span,
     pub block: Box<'a, BlockStatement<'a>>,
     pub handler: Option<Box<'a, CatchClause<'a>>>,
-    #[visit_as(FinallyClause)]
+    #[visit(as(FinallyClause))]
     pub finalizer: Option<Box<'a, BlockStatement<'a>>>,
 }
 
@@ -1428,7 +1428,7 @@ pub struct BindingRestElement<'a> {
 /// Function Definitions
 #[ast(visit)]
 #[scope(
-    // `flags` passed in to visitor via parameter defined by `#[visit_args(flags = ...)]` on parents
+    // `flags` passed in to visitor via parameter defined by `#[visit(args(flags = ...))]` on parents
     flags(flags),
     strict_if(self.is_strict()),
 )]
@@ -1582,7 +1582,7 @@ pub struct Class<'a> {
     pub id: Option<BindingIdentifier<'a>>,
     #[scope(enter_before)]
     pub type_parameters: Option<Box<'a, TSTypeParameterDeclaration<'a>>>,
-    #[visit_as(ClassHeritage)]
+    #[visit(as(ClassHeritage))]
     pub super_class: Option<Expression<'a>>,
     pub super_type_parameters: Option<Box<'a, TSTypeParameterInstantiation<'a>>>,
     pub implements: Option<Vec<'a, TSClassImplements<'a>>>,
@@ -1632,12 +1632,12 @@ pub struct MethodDefinition<'a> {
     pub span: Span,
     pub decorators: Vec<'a, Decorator<'a>>,
     pub key: PropertyKey<'a>,
-    #[visit_args(flags = match self.kind {
+    #[visit(args(flags = match self.kind {
         MethodDefinitionKind::Get => ScopeFlags::Function | ScopeFlags::GetAccessor,
         MethodDefinitionKind::Set => ScopeFlags::Function | ScopeFlags::SetAccessor,
         MethodDefinitionKind::Constructor => ScopeFlags::Function | ScopeFlags::Constructor,
         MethodDefinitionKind::Method => ScopeFlags::Function,
-    })]
+    }))]
     pub value: Box<'a, Function<'a>>, // FunctionExpression
     pub kind: MethodDefinitionKind,
     pub computed: bool,
@@ -1953,7 +1953,7 @@ inherit_variants! {
 #[cfg_attr(feature = "serialize", derive(Serialize, Tsify))]
 #[serde(untagged)]
 pub enum ExportDefaultDeclarationKind<'a> {
-    #[visit_args(flags = ScopeFlags::Function)]
+    #[visit(args(flags = ScopeFlags::Function))]
     FunctionDeclaration(Box<'a, Function<'a>>) = 64,
     ClassDeclaration(Box<'a, Class<'a>>) = 65,
 

crates/oxc_ast/src/ast/jsx.rs

@@ -1,8 +1,8 @@
 //! [JSX](https://facebook.github.io/jsx)
 
-// NB: `#[span]`, `#[scope(...)]`, `#[visit(...)]`, `#[visit_as(...)]` and `#[visit_args(...)]` do
-// not do anything to the code, They are purely markers for codegen used in
-// `tasts/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in that crate.
+// NB: `#[span]`, `#[scope(...)]` and `#[visit(...)]` do NOT do anything to the code.
+// They are purely markers for codegen used in
+// `tasks/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in those crates.
 
 // Silence erroneous warnings from Rust Analyser for `#[derive(Tsify)]`
 #![allow(non_snake_case)]

crates/oxc_ast/src/ast/literal.rs

@@ -1,8 +1,8 @@
 //! Literals
 
-// NB: `#[span]`, `#[scope(...)]`, `#[visit(...)]`, `#[visit_as(...)]` and `#[visit_args(...)]` do
-// not do anything to the code, They are purely markers for codegen used in
-// `tasts/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in that crate.
+// NB: `#[span]`, `#[scope(...)]` and `#[visit(...)]` do NOT do anything to the code.
+// They are purely markers for codegen used in
+// `tasks/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in those crates.
 
 // Silence erroneous warnings from Rust Analyser for `#[derive(Tsify)]`
 #![allow(non_snake_case)]

crates/oxc_ast/src/ast/ts.rs

@@ -3,9 +3,9 @@
 //! [AST Spec](https://github.com/typescript-eslint/typescript-eslint/tree/main/packages/ast-spec)
 //! [Archived TypeScript spec](https://github.com/microsoft/TypeScript/blob/3c99d50da5a579d9fa92d02664b1b66d4ff55944/doc/spec-ARCHIVED.md)
 
-// NB: `#[span]`, `#[scope(...)]`, `#[visit(...)]`, `#[visit_as(...)]` and `#[visit_args(...)]` do
-// not do anything to the code, They are purely markers for codegen used in
-// `tasts/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in that crate.
+// NB: `#[span]`, `#[scope(...)]` and `#[visit(...)]` do NOT do anything to the code.
+// They are purely markers for codegen used in
+// `tasks/ast_codegen` and `crates/oxc_traverse/scripts`. See docs in those crates.
 
 // Silence erroneous warnings from Rust Analyser for `#[derive(Tsify)]`
 #![allow(non_snake_case)]

tasks/ast_codegen/src/generators/ast_kind.rs

@@ -2,7 +2,10 @@ use itertools::Itertools;
 use quote::quote;
 use syn::{parse_quote, Arm, Ident, Type, Variant};
 
-use crate::{schema::RType, util::TypeExt, CodegenCtx, Generator, GeneratorOutput, TypeRef};
+use crate::{
+    markers::get_visit_markers, schema::RType, util::TypeExt, CodegenCtx, Generator,
+    GeneratorOutput, TypeRef,
+};
 
 use super::generated_header;
 
@@ -91,35 +94,27 @@ pub fn process_types(ty: &TypeRef) -> Vec<(Ident, Type)> {
             .item
             .variants
             .iter()
-            .filter_map(|it| {
-                it.attrs
-                    .iter()
-                    .find(|it| it.path().is_ident("visit_as"))
-                    .map(|attr| (it, attr))
-                    .map(|(it, attr)| {
-                        assert!(
-                            it.fields.len() == 1,
-                            "visit_as only supports single argument fields."
-                        );
-                        let field = it.fields.iter().next().unwrap();
-                        let type_name = field.ty.get_ident().inner_ident();
-                        (attr.parse_args().unwrap(), parse_quote!(#type_name<'a>))
-                    })
+            .map(|it| (it, get_visit_markers(&it.attrs).transpose().unwrap()))
+            .filter(|(_, markers)| markers.as_ref().is_some_and(|mk| mk.visit_as.is_some()))
+            .filter_map(|(it, markers)| {
+                markers.map(|markers| {
+                    let field = it.fields.iter().next().unwrap();
+                    let type_name = field.ty.get_ident().inner_ident();
+                    (markers.visit_as.expect("Already checked"), parse_quote!(#type_name<'a>))
+                })
             })
             .collect_vec(),
         RType::Struct(struct_) => struct_
             .item
             .fields
             .iter()
-            .filter_map(|it| {
-                it.attrs
-                    .iter()
-                    .find(|it| it.path().is_ident("visit_as"))
-                    .map(|attr| (it, attr))
-                    .map(|(field, attr)| {
-                        let type_name = field.ty.get_ident().inner_ident();
-                        (attr.parse_args().unwrap(), parse_quote!(#type_name<'a>))
-                    })
+            .map(|it| (it, get_visit_markers(&it.attrs).transpose().unwrap()))
+            .filter(|(_, markers)| markers.as_ref().is_some_and(|mk| mk.visit_as.is_some()))
+            .filter_map(|(field, markers)| {
+                markers.map(|markers| {
+                    let type_name = field.ty.get_ident().inner_ident();
+                    (markers.visit_as.expect("Already checked"), parse_quote!(#type_name<'a>))
+                })
             })
             .collect_vec(),
         _ => panic!(),