Remove NtPath.

compiler/rustc_ast/src/ast_traits.rs

@@ -200,14 +200,12 @@ impl HasTokens for Nonterminal {
     fn tokens(&self) -> Option<&LazyAttrTokenStream> {
         match self {
             Nonterminal::NtExpr(expr) | Nonterminal::NtLiteral(expr) => expr.tokens(),
-            Nonterminal::NtPath(path) => path.tokens(),
             Nonterminal::NtBlock(block) => block.tokens(),
         }
     }
     fn tokens_mut(&mut self) -> Option<&mut Option<LazyAttrTokenStream>> {
         match self {
             Nonterminal::NtExpr(expr) | Nonterminal::NtLiteral(expr) => expr.tokens_mut(),
-            Nonterminal::NtPath(path) => path.tokens_mut(),
             Nonterminal::NtBlock(block) => block.tokens_mut(),
         }
     }

compiler/rustc_ast/src/attr/mod.rs

@@ -364,14 +364,12 @@ impl MetaItem {
                 let span = span.with_hi(segments.last().unwrap().ident.span.hi());
                 Path { span, segments, tokens: None }
             }
-            Some(TokenTree::Token(Token { kind: token::Interpolated(nt), .. }, _)) => match &**nt {
-                token::Nonterminal::NtPath(path) => (**path).clone(),
-                _ => return None,
-            },
             Some(TokenTree::Delimited(
                 _span,
                 _spacing,
-                Delimiter::Invisible(InvisibleOrigin::MetaVar(MetaVarKind::Meta)),
+                Delimiter::Invisible(InvisibleOrigin::MetaVar(
+                    MetaVarKind::Meta | MetaVarKind::Path,
+                )),
                 _stream,
             )) => {
                 // This path is currently unreachable in the test suite.

compiler/rustc_ast/src/mut_visit.rs

@@ -803,7 +803,6 @@ fn visit_nonterminal<T: MutVisitor>(vis: &mut T, nt: &mut token::Nonterminal) {
         token::NtBlock(block) => vis.visit_block(block),
         token::NtExpr(expr) => vis.visit_expr(expr),
         token::NtLiteral(expr) => vis.visit_expr(expr),
-        token::NtPath(path) => vis.visit_path(path),
     }
 }
 

compiler/rustc_ast/src/token.rs

@@ -620,8 +620,7 @@ impl Token {
                 matches!(&**nt,
                     NtBlock(..)   |
                     NtExpr(..)    |
-                    NtLiteral(..) |
-                    NtPath(..)
+                    NtLiteral(..)
                 ),
             OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
                 MetaVarKind::Block |
@@ -657,7 +656,6 @@ impl Token {
                 matches!(&**nt,
                     | NtExpr(..)
                     | NtLiteral(..)
-                    | NtPath(..)
                 ),
             OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
                 MetaVarKind::Expr { .. } |
@@ -686,7 +684,6 @@ impl Token {
             Lifetime(..)                | // lifetime bound in trait object
             Lt | BinOp(Shl)             | // associated path
             PathSep                      => true, // global path
-            Interpolated(ref nt) => matches!(&**nt, NtPath(..)),
             OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(
                 MetaVarKind::Ty |
                 MetaVarKind::Path
@@ -845,28 +842,19 @@ impl Token {
         self.ident().is_some_and(|(ident, _)| ident.name == name)
     }
 
-    /// Returns `true` if the token is an interpolated path.
-    fn is_whole_path(&self) -> bool {
-        if let Interpolated(nt) = &self.kind
-            && let NtPath(..) = &**nt
-        {
-            return true;
-        }
-
-        false
-    }
-
     /// Is this a pre-parsed expression dropped into the token stream
     /// (which happens while parsing the result of macro expansion)?
     pub fn is_whole_expr(&self) -> bool {
         #[allow(irrefutable_let_patterns)] // FIXME: temporary
         if let Interpolated(nt) = &self.kind
-            && let NtExpr(_) | NtLiteral(_) | NtPath(_) | NtBlock(_) = &**nt
+            && let NtExpr(_) | NtLiteral(_) | NtBlock(_) = &**nt
         {
-            return true;
+            true
+        } else if matches!(self.is_metavar_seq(), Some(MetaVarKind::Path)) {
+            true
+        } else {
+            false
         }
-
-        false
     }
 
     /// Is the token an interpolated block (`$b:block`)?
@@ -892,7 +880,7 @@ impl Token {
     pub fn is_path_start(&self) -> bool {
         self == &PathSep
             || self.is_qpath_start()
-            || self.is_whole_path()
+            || matches!(self.is_metavar_seq(), Some(MetaVarKind::Path))
             || self.is_path_segment_keyword()
             || self.is_ident() && !self.is_reserved_ident()
     }
@@ -1066,7 +1054,6 @@ pub enum Nonterminal {
     NtBlock(P<ast::Block>),
     NtExpr(P<ast::Expr>),
     NtLiteral(P<ast::Expr>),
-    NtPath(P<ast::Path>),
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, HashStable_Generic)]
@@ -1157,7 +1144,6 @@ impl Nonterminal {
         match self {
             NtBlock(block) => block.span,
             NtExpr(expr) | NtLiteral(expr) => expr.span,
-            NtPath(path) => path.span,
         }
     }
 
@@ -1166,7 +1152,6 @@ impl Nonterminal {
             NtBlock(..) => "block",
             NtExpr(..) => "expression",
             NtLiteral(..) => "literal",
-            NtPath(..) => "path",
         }
     }
 }
@@ -1187,7 +1172,6 @@ impl fmt::Debug for Nonterminal {
             NtBlock(..) => f.pad("NtBlock(..)"),
             NtExpr(..) => f.pad("NtExpr(..)"),
             NtLiteral(..) => f.pad("NtLiteral(..)"),
-            NtPath(..) => f.pad("NtPath(..)"),
         }
     }
 }

compiler/rustc_ast/src/tokenstream.rs

@@ -462,7 +462,6 @@ impl TokenStream {
     pub fn from_nonterminal_ast(nt: &Nonterminal) -> TokenStream {
         match nt {
             Nonterminal::NtBlock(block) => TokenStream::from_ast(block),
-            Nonterminal::NtPath(path) => TokenStream::from_ast(path),
             Nonterminal::NtExpr(expr) | Nonterminal::NtLiteral(expr) => TokenStream::from_ast(expr),
         }
     }

compiler/rustc_expand/src/mbe/transcribe.rs

@@ -324,6 +324,9 @@ pub(super) fn transcribe<'a>(
                         MatchedSingle(ParseNtResult::Meta(meta)) => {
                             mk_delimited(MetaVarKind::Meta, TokenStream::from_ast(meta))
                         }
+                        MatchedSingle(ParseNtResult::Path(path)) => {
+                            mk_delimited(MetaVarKind::Path, TokenStream::from_ast(path))
+                        }
                         MatchedSingle(ParseNtResult::Vis(vis)) => {
                             mk_delimited(MetaVarKind::Vis, TokenStream::from_ast(vis))
                         }

compiler/rustc_parse/src/parser/expr.rs

@@ -4,7 +4,7 @@ use core::mem;
 use core::ops::ControlFlow;
 
 use ast::mut_visit::{self, MutVisitor};
-use ast::token::IdentIsRaw;
+use ast::token::{IdentIsRaw, MetaVarKind};
 use ast::{CoroutineKind, ForLoopKind, GenBlockKind, MatchKind, Pat, Path, PathSegment, Recovered};
 use rustc_ast::ptr::P;
 use rustc_ast::token::{self, Delimiter, Token, TokenKind};
@@ -1382,24 +1382,24 @@ impl<'a> Parser<'a> {
     fn parse_expr_bottom(&mut self) -> PResult<'a, P<Expr>> {
         maybe_recover_from_interpolated_ty_qpath!(self, true);
 
+        let span = self.token.span;
         if let token::Interpolated(nt) = &self.token.kind {
             match &**nt {
                 token::NtExpr(e) | token::NtLiteral(e) => {
                     let e = e.clone();
                     self.bump();
                     return Ok(e);
                 }
-                token::NtPath(path) => {
-                    let path = (**path).clone();
-                    self.bump();
-                    return Ok(self.mk_expr(self.prev_token.span, ExprKind::Path(None, path)));
-                }
                 token::NtBlock(block) => {
                     let block = block.clone();
                     self.bump();
                     return Ok(self.mk_expr(self.prev_token.span, ExprKind::Block(block, None)));
                 }
             };
+        } else if let Some(path) = self.eat_metavar_seq(MetaVarKind::Path, |this| {
+            this.collect_tokens_no_attrs(|this| this.parse_path(PathStyle::Type))
+        }) {
+            return Ok(self.mk_expr(span, ExprKind::Path(None, path)));
         }
 
         // Outer attributes are already parsed and will be

compiler/rustc_parse/src/parser/mod.rs

@@ -1771,6 +1771,7 @@ pub enum ParseNtResult {
     Pat(P<ast::Pat>, NtPatKind),
     Ty(P<ast::Ty>),
     Meta(P<ast::AttrItem>),
+    Path(P<ast::Path>),
     Vis(P<ast::Visibility>),
 
     /// This variant will eventually be removed, along with `Token::Interpolate`.

compiler/rustc_parse/src/parser/nonterminal.rs

@@ -50,7 +50,7 @@ impl<'a> Parser<'a> {
             match nt {
                 NtExpr(_)
                 | NtLiteral(_) // `true`, `false`
-                | NtPath(_) => true,
+                => true,
 
                 NtBlock(_) => false,
             }
@@ -96,7 +96,6 @@ impl<'a> Parser<'a> {
                 token::NtLifetime(..) => true,
                 token::Interpolated(nt) => match &**nt {
                     NtBlock(_) | NtExpr(_) | NtLiteral(_) => true,
-                    NtPath(_) => false,
                 },
                 token::OpenDelim(Delimiter::Invisible(InvisibleOrigin::MetaVar(k))) => match k {
                     MetaVarKind::Block
@@ -203,7 +202,9 @@ impl<'a> Parser<'a> {
                 };
             }
             NonterminalKind::Path => {
-                NtPath(P(self.collect_tokens_no_attrs(|this| this.parse_path(PathStyle::Type))?))
+                return Ok(ParseNtResult::Path(P(
+                    self.collect_tokens_no_attrs(|this| this.parse_path(PathStyle::Type))?
+                )));
             }
             NonterminalKind::Meta => {
                 return Ok(ParseNtResult::Meta(P(self.parse_attr_item(ForceCollect::Yes)?)));

compiler/rustc_parse/src/parser/path.rs

@@ -16,9 +16,8 @@ use tracing::debug;
 
 use super::ty::{AllowPlus, RecoverQPath, RecoverReturnSign};
 use super::{Parser, Restrictions, TokenType};
-use crate::errors::{PathSingleColon, PathTripleColon};
+use crate::errors::{self, PathSingleColon, PathTripleColon};
 use crate::parser::{CommaRecoveryMode, RecoverColon, RecoverComma};
-use crate::{errors, maybe_whole};
 
 /// Specifies how to parse a path.
 #[derive(Copy, Clone, PartialEq)]
@@ -196,7 +195,11 @@ impl<'a> Parser<'a> {
             }
         };
 
-        maybe_whole!(self, NtPath, |path| reject_generics_if_mod_style(self, path.into_inner()));
+        if let Some(path) =
+            self.eat_metavar_seq(MetaVarKind::Path, |this| this.parse_path(PathStyle::Type))
+        {
+            return Ok(reject_generics_if_mod_style(self, path));
+        }
 
         if let Some(MetaVarKind::Ty) = self.token.is_metavar_seq() {
             let mut snapshot = self.create_snapshot_for_diagnostic();

tests/ui/imports/import-prefix-macro-2.rs

@@ -8,7 +8,7 @@ mod a {
 }
 
 macro_rules! import {
-    ($p: path) => (use ::$p {S, Z}); //~ERROR  expected identifier, found `a::b::c`
+    ($p: path) => (use ::$p {S, Z}); //~ERROR expected identifier, found metavariable
 }
 
 import! { a::b::c }

tests/ui/imports/import-prefix-macro-2.stderr

@@ -1,8 +1,8 @@
-error: expected identifier, found `a::b::c`
+error: expected identifier, found metavariable
   --> $DIR/import-prefix-macro-2.rs:11:26
    |
 LL |     ($p: path) => (use ::$p {S, Z});
-   |                          ^^ expected identifier
+   |                          ^^ expected identifier, found metavariable
 ...
 LL | import! { a::b::c }
    | ------------------- in this macro invocation

tests/ui/macros/nonterminal-matching.rs

@@ -31,7 +31,7 @@ macro_rules! foo {
     (tt $x:tt) => { bar!(tt $x); };
     (expr $x:expr) => { bar!(expr $x); }; //~ ERROR: no rules expected expression `3`
     (literal $x:literal) => { bar!(literal $x); }; //~ ERROR: no rules expected literal `4`
-    (path $x:path) => { bar!(path $x); }; //~ ERROR: no rules expected path `a::b::c`
+    (path $x:path) => { bar!(path $x); }; //~ ERROR: no rules expected `path` metavariable
     (stmt $x:stmt) => { bar!(stmt $x); }; //~ ERROR: no rules expected `stmt` metavariable
 }
 

tests/ui/macros/nonterminal-matching.stderr

@@ -67,7 +67,7 @@ LL |     (literal 4) => {};
    = help: try using `:tt` instead in the macro definition
    = note: this error originates in the macro `foo` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: no rules expected path `a::b::c`
+error: no rules expected `path` metavariable
   --> $DIR/nonterminal-matching.rs:34:35
    |
 LL |     (path $x:path) => { bar!(path $x); };