review comment: Remove AST AnonTy

compiler/rustc_ast/src/ast.rs

@@ -2096,9 +2096,6 @@ pub enum TyKind {
     Err,
     /// Placeholder for a `va_list`.
     CVarArgs,
-    /// Placeholder for "anonymous enums", which don't exist, but keeping their
-    /// information around lets us produce better diagnostics.
-    AnonEnum(Vec<P<Ty>>),
 }
 
 impl TyKind {

compiler/rustc_ast/src/mut_visit.rs

@@ -470,7 +470,7 @@ pub fn noop_visit_ty<T: MutVisitor>(ty: &mut P<Ty>, vis: &mut T) {
             vis.visit_fn_decl(decl);
             vis.visit_span(decl_span);
         }
-        TyKind::AnonEnum(tys) | TyKind::Tup(tys) => visit_vec(tys, |ty| vis.visit_ty(ty)),
+        TyKind::Tup(tys) => visit_vec(tys, |ty| vis.visit_ty(ty)),
         TyKind::Paren(ty) => vis.visit_ty(ty),
         TyKind::Path(qself, path) => {
             vis.visit_qself(qself);

compiler/rustc_ast/src/visit.rs

@@ -400,7 +400,7 @@ pub fn walk_ty<'a, V: Visitor<'a>>(visitor: &mut V, typ: &'a Ty) {
             walk_list!(visitor, visit_lifetime, opt_lifetime, LifetimeCtxt::Ref);
             visitor.visit_ty(&mutable_type.ty)
         }
-        TyKind::AnonEnum(tys) | TyKind::Tup(tys) => {
+        TyKind::Tup(tys) => {
             walk_list!(visitor, visit_ty, tys);
         }
         TyKind::BareFn(function_declaration) => {

compiler/rustc_ast_lowering/src/lib.rs

@@ -1235,7 +1235,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         let kind = match &t.kind {
             TyKind::Infer => hir::TyKind::Infer,
             TyKind::Err => hir::TyKind::Err,
-            TyKind::AnonEnum(_) => hir::TyKind::Err,
             TyKind::Slice(ty) => hir::TyKind::Slice(self.lower_ty(ty, itctx)),
             TyKind::Ptr(mt) => hir::TyKind::Ptr(self.lower_mt(mt, itctx)),
             TyKind::Ref(region, mt) => {

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -1041,9 +1041,6 @@ impl<'a> State<'a> {
                 }
                 self.pclose();
             }
-            ast::TyKind::AnonEnum(elts) => {
-                self.strsep("|", false, Inconsistent, elts, |s, ty| s.print_type(ty));
-            }
             ast::TyKind::Paren(typ) => {
                 self.popen();
                 self.print_type(typ);

compiler/rustc_parse/src/parser/ty.rs

@@ -390,7 +390,7 @@ impl<'a> Parser<'a> {
                     .join("\n"),
             ));
             err.emit();
-            return Ok(self.mk_ty(lo.to(self.prev_token.span), TyKind::AnonEnum(types)));
+            return Ok(self.mk_ty(lo.to(self.prev_token.span), TyKind::Err));
         }
         if allow_qpath_recovery { self.maybe_recover_from_bad_qpath(ty) } else { Ok(ty) }
     }

compiler/rustc_passes/src/hir_stats.rs

@@ -579,7 +579,6 @@ impl<'v> ast_visit::Visitor<'v> for StatCollector<'v> {
             [
                 Slice,
                 Array,
-                AnonEnum,
                 Ptr,
                 Ref,
                 BareFn,

src/tools/rustfmt/src/types.rs

@@ -839,9 +839,7 @@ impl Rewrite for ast::Ty {
                 })
             }
             ast::TyKind::CVarArgs => Some("...".to_owned()),
-            ast::TyKind::AnonEnum(_) | ast::TyKind::Err => {
+            ast::TyKind::Err => Some(context.snippet(self.span).to_owned()),
-                Some(context.snippet(self.span).to_owned())
-            }
             ast::TyKind::Typeof(ref anon_const) => rewrite_call(
                 context,
                 "typeof",