[experiment] don't use &mut P<T> in AST visitors

Author: fee1-dead

compiler/rustc_ast/src/mut_visit.rs

@@ -83,15 +83,15 @@ pub trait MutVisitor: Sized {
         walk_use_tree(self, use_tree);
     }
 
-    fn visit_foreign_item(&mut self, ni: &mut P<ForeignItem>) {
+    fn visit_foreign_item(&mut self, ni: &mut ForeignItem) {
         walk_item(self, ni);
     }
 
     fn flat_map_foreign_item(&mut self, ni: P<ForeignItem>) -> SmallVec<[P<ForeignItem>; 1]> {
         walk_flat_map_foreign_item(self, ni)
     }
 
-    fn visit_item(&mut self, i: &mut P<Item>) {
+    fn visit_item(&mut self, i: &mut Item) {
         walk_item(self, i);
     }
 
@@ -111,7 +111,7 @@ pub trait MutVisitor: Sized {
         walk_flat_map_field_def(self, fd)
     }
 
-    fn visit_assoc_item(&mut self, i: &mut P<AssocItem>, ctxt: AssocCtxt) {
+    fn visit_assoc_item(&mut self, i: &mut AssocItem, ctxt: AssocCtxt) {
         walk_assoc_item(self, i, ctxt)
     }
 
@@ -123,11 +123,11 @@ pub trait MutVisitor: Sized {
         walk_flat_map_assoc_item(self, i, ctxt)
     }
 
-    fn visit_contract(&mut self, c: &mut P<FnContract>) {
+    fn visit_contract(&mut self, c: &mut FnContract) {
         walk_contract(self, c);
     }
 
-    fn visit_fn_decl(&mut self, d: &mut P<FnDecl>) {
+    fn visit_fn_decl(&mut self, d: &mut FnDecl) {
         walk_fn_decl(self, d);
     }
 
@@ -144,7 +144,7 @@ pub trait MutVisitor: Sized {
         walk_closure_binder(self, b);
     }
 
-    fn visit_block(&mut self, b: &mut P<Block>) {
+    fn visit_block(&mut self, b: &mut Block) {
         walk_block(self, b);
     }
 
@@ -160,21 +160,21 @@ pub trait MutVisitor: Sized {
         walk_flat_map_arm(self, arm)
     }
 
-    fn visit_pat(&mut self, p: &mut P<Pat>) {
+    fn visit_pat(&mut self, p: &mut Pat) {
         walk_pat(self, p);
     }
 
     fn visit_anon_const(&mut self, c: &mut AnonConst) {
         walk_anon_const(self, c);
     }
 
-    fn visit_expr(&mut self, e: &mut P<Expr>) {
+    fn visit_expr(&mut self, e: &mut Expr) {
         walk_expr(self, e);
     }
 
     /// This method is a hack to workaround unstable of `stmt_expr_attributes`.
     /// It can be removed once that feature is stabilized.
-    fn visit_method_receiver_expr(&mut self, ex: &mut P<Expr>) {
+    fn visit_method_receiver_expr(&mut self, ex: &mut Expr) {
         self.visit_expr(ex)
     }
 
@@ -186,11 +186,11 @@ pub trait MutVisitor: Sized {
         walk_generic_arg(self, arg);
     }
 
-    fn visit_ty(&mut self, t: &mut P<Ty>) {
+    fn visit_ty(&mut self, t: &mut Ty) {
         walk_ty(self, t);
     }
 
-    fn visit_ty_pat(&mut self, t: &mut P<TyPat>) {
+    fn visit_ty_pat(&mut self, t: &mut TyPat) {
         walk_ty_pat(self, t);
     }
 
@@ -246,7 +246,7 @@ pub trait MutVisitor: Sized {
         walk_parenthesized_parameter_data(self, p);
     }
 
-    fn visit_local(&mut self, l: &mut P<Local>) {
+    fn visit_local(&mut self, l: &mut Local) {
         walk_local(self, l);
     }
 
@@ -527,8 +527,8 @@ fn walk_assoc_item_constraint<T: MutVisitor>(
     vis.visit_span(span);
 }
 
-pub fn walk_ty<T: MutVisitor>(vis: &mut T, ty: &mut P<Ty>) {
-    let Ty { id, kind, span, tokens: _ } = ty.deref_mut();
+pub fn walk_ty<T: MutVisitor>(vis: &mut T, ty: &mut Ty) {
+    let Ty { id, kind, span, tokens: _ } = ty;
     vis.visit_id(id);
     match kind {
         TyKind::Err(_guar) => {}
@@ -579,8 +579,8 @@ pub fn walk_ty<T: MutVisitor>(vis: &mut T, ty: &mut P<Ty>) {
     vis.visit_span(span);
 }
 
-pub fn walk_ty_pat<T: MutVisitor>(vis: &mut T, ty: &mut P<TyPat>) {
-    let TyPat { id, kind, span, tokens: _ } = ty.deref_mut();
+pub fn walk_ty_pat<T: MutVisitor>(vis: &mut T, ty: &mut TyPat) {
+    let TyPat { id, kind, span, tokens: _ } = ty;
     vis.visit_id(id);
     match kind {
         TyPatKind::Range(start, end, _include_end) => {
@@ -671,8 +671,8 @@ fn walk_parenthesized_parameter_data<T: MutVisitor>(vis: &mut T, args: &mut Pare
     vis.visit_span(inputs_span);
 }
 
-fn walk_local<T: MutVisitor>(vis: &mut T, local: &mut P<Local>) {
-    let Local { id, super_, pat, ty, kind, span, colon_sp, attrs, tokens: _ } = local.deref_mut();
+fn walk_local<T: MutVisitor>(vis: &mut T, local: &mut Local) {
+    let Local { id, super_, pat, ty, kind, span, colon_sp, attrs, tokens: _ } = local;
     visit_opt(super_, |sp| vis.visit_span(sp));
     vis.visit_id(id);
     visit_attrs(vis, attrs);
@@ -809,8 +809,8 @@ fn walk_fn<T: MutVisitor>(vis: &mut T, kind: FnKind<'_>) {
     }
 }
 
-fn walk_contract<T: MutVisitor>(vis: &mut T, contract: &mut P<FnContract>) {
-    let FnContract { requires, ensures } = contract.deref_mut();
+fn walk_contract<T: MutVisitor>(vis: &mut T, contract: &mut FnContract) {
+    let FnContract { requires, ensures } = contract;
     if let Some(pred) = requires {
         vis.visit_expr(pred);
     }
@@ -819,8 +819,8 @@ fn walk_contract<T: MutVisitor>(vis: &mut T, contract: &mut P<FnContract>) {
     }
 }
 
-fn walk_fn_decl<T: MutVisitor>(vis: &mut T, decl: &mut P<FnDecl>) {
-    let FnDecl { inputs, output } = decl.deref_mut();
+fn walk_fn_decl<T: MutVisitor>(vis: &mut T, decl: &mut FnDecl) {
+    let FnDecl { inputs, output } = decl;
     inputs.flat_map_in_place(|param| vis.flat_map_param(param));
     vis.visit_fn_ret_ty(output);
 }
@@ -1023,8 +1023,8 @@ fn walk_mt<T: MutVisitor>(vis: &mut T, MutTy { ty, mutbl: _ }: &mut MutTy) {
     vis.visit_ty(ty);
 }
 
-pub fn walk_block<T: MutVisitor>(vis: &mut T, block: &mut P<Block>) {
-    let Block { id, stmts, rules: _, span, tokens: _ } = block.deref_mut();
+pub fn walk_block<T: MutVisitor>(vis: &mut T, block: &mut Block) {
+    let Block { id, stmts, rules: _, span, tokens: _ } = block;
     vis.visit_id(id);
     stmts.flat_map_in_place(|stmt| vis.flat_map_stmt(stmt));
     vis.visit_span(span);
@@ -1123,11 +1123,11 @@ pub fn walk_crate<T: MutVisitor>(vis: &mut T, krate: &mut Crate) {
     vis.visit_span(inject_use_span);
 }
 
-pub fn walk_item(visitor: &mut impl MutVisitor, item: &mut P<Item<impl WalkItemKind<Ctxt = ()>>>) {
+pub fn walk_item(visitor: &mut impl MutVisitor, item: &mut Item<impl WalkItemKind<Ctxt = ()>>) {
     walk_item_ctxt(visitor, item, ())
 }
 
-pub fn walk_assoc_item(visitor: &mut impl MutVisitor, item: &mut P<AssocItem>, ctxt: AssocCtxt) {
+pub fn walk_assoc_item(visitor: &mut impl MutVisitor, item: &mut AssocItem, ctxt: AssocCtxt) {
     walk_item_ctxt(visitor, item, ctxt)
 }
 
@@ -1200,8 +1200,8 @@ impl WalkItemKind for ForeignItemKind {
     }
 }
 
-pub fn walk_pat<T: MutVisitor>(vis: &mut T, pat: &mut P<Pat>) {
-    let Pat { id, kind, span, tokens: _ } = pat.deref_mut();
+pub fn walk_pat<T: MutVisitor>(vis: &mut T, pat: &mut Pat) {
+    let Pat { id, kind, span, tokens: _ } = pat;
     vis.visit_id(id);
     match kind {
         PatKind::Err(_guar) => {}

compiler/rustc_ast/src/visit.rs

@@ -406,10 +406,10 @@ macro_rules! common_visitor_and_walkers {
 
         fn walk_item_ctxt<$($lt,)? V: $Visitor$(<$lt>)?, K: WalkItemKind>(
             visitor: &mut V,
-            item: &$($mut P<Item<K>>)? $($lt Item<K>)?,
+            item: &$($mut)? $($lt)? Item<K>,
             ctxt: K::Ctxt,
         ) $(-> <V as Visitor<$lt>>::Result)? {
-            let Item { attrs, id, kind, vis, span, tokens: _ } = &$($mut *)? *item;
+            let Item { attrs, id, kind, vis, span, tokens: _ } = item;
             try_visit!(visit_id(visitor, id));
             walk_list!(visitor, visit_attribute, attrs);
             try_visit!(visitor.visit_vis(vis));

compiler/rustc_builtin_macros/src/cfg_eval.rs

@@ -155,13 +155,13 @@ impl CfgEval<'_> {
 
 impl MutVisitor for CfgEval<'_> {
     #[instrument(level = "trace", skip(self))]
-    fn visit_expr(&mut self, expr: &mut P<ast::Expr>) {
+    fn visit_expr(&mut self, expr: &mut ast::Expr) {
         self.0.configure_expr(expr, false);
         mut_visit::walk_expr(self, expr);
     }
 
     #[instrument(level = "trace", skip(self))]
-    fn visit_method_receiver_expr(&mut self, expr: &mut P<ast::Expr>) {
+    fn visit_method_receiver_expr(&mut self, expr: &mut ast::Expr) {
         self.0.configure_expr(expr, true);
         mut_visit::walk_expr(self, expr);
     }

compiler/rustc_builtin_macros/src/deriving/coerce_pointee.rs

@@ -1,5 +1,4 @@
 use ast::HasAttrs;
-use ast::ptr::P;
 use rustc_ast::mut_visit::MutVisitor;
 use rustc_ast::visit::BoundKind;
 use rustc_ast::{
@@ -378,11 +377,11 @@ struct TypeSubstitution<'a> {
 }
 
 impl<'a> ast::mut_visit::MutVisitor for TypeSubstitution<'a> {
-    fn visit_ty(&mut self, ty: &mut P<ast::Ty>) {
+    fn visit_ty(&mut self, ty: &mut ast::Ty) {
         if let Some(name) = ty.kind.is_simple_path()
             && name == self.from_name
         {
-            **ty = self.to_ty.clone();
+            *ty = self.to_ty.clone();
             self.rewritten = true;
         } else {
             ast::mut_visit::walk_ty(self, ty);

compiler/rustc_builtin_macros/src/test_harness.rs

@@ -128,9 +128,7 @@ impl<'a> MutVisitor for TestHarnessGenerator<'a> {
         c.items.push(mk_main(&mut self.cx));
     }
 
-    fn visit_item(&mut self, item: &mut P<ast::Item>) {
-        let item = &mut **item;
-
+    fn visit_item(&mut self, item: &mut ast::Item) {
         if let Some(name) = get_test_name(&item) {
             debug!("this is a test item");
 
@@ -193,7 +191,7 @@ struct EntryPointCleaner<'a> {
 }
 
 impl<'a> MutVisitor for EntryPointCleaner<'a> {
-    fn visit_item(&mut self, item: &mut P<ast::Item>) {
+    fn visit_item(&mut self, item: &mut ast::Item) {
         self.depth += 1;
         ast::mut_visit::walk_item(self, item);
         self.depth -= 1;

compiler/rustc_expand/src/config.rs

@@ -2,7 +2,6 @@
 
 use std::iter;
 
-use rustc_ast::ptr::P;
 use rustc_ast::token::{Delimiter, Token, TokenKind};
 use rustc_ast::tokenstream::{
     AttrTokenStream, AttrTokenTree, LazyAttrTokenStream, Spacing, TokenTree,
@@ -433,7 +432,7 @@ impl<'a> StripUnconfigured<'a> {
     }
 
     #[instrument(level = "trace", skip(self))]
-    pub fn configure_expr(&self, expr: &mut P<ast::Expr>, method_receiver: bool) {
+    pub fn configure_expr(&self, expr: &mut ast::Expr, method_receiver: bool) {
         if !method_receiver {
             for attr in expr.attrs.iter() {
                 self.maybe_emit_expr_attr_err(attr);