Generated code spans now point to callsite parameters (where applicable)

src/libsyntax/ext/tt/macro_parser.rs

@@ -79,8 +79,8 @@ pub use self::ParseResult::*;
 use self::TokenTreeOrTokenTreeVec::*;
 
 use ast;
-use ast::{TokenTree, Name};
-use codemap::{BytePos, mk_sp, Span};
+use ast::{TokenTree, Name, Ident};
+use codemap::{BytePos, mk_sp, Span, Spanned};
 use codemap;
 use parse::lexer::*; //resolve bug?
 use parse::ParseSess;
@@ -526,7 +526,10 @@ pub fn parse_nt(p: &mut Parser, sp: Span, name: &str) -> Nonterminal {
         "ty" => token::NtTy(panictry!(p.parse_ty())),
         // this could be handled like a token, since it is one
         "ident" => match p.token {
-            token::Ident(sn,b) => { panictry!(p.bump()); token::NtIdent(Box::new(sn),b) }
+            token::Ident(sn,b) => {
+                panictry!(p.bump());
+                token::NtIdent(Box::new(Spanned::<Ident>{node: sn, span: p.span}),b)
+            }
             _ => {
                 let token_str = pprust::token_to_string(&p.token);
                 panic!(p.fatal(&format!("expected ident, found {}",

src/libsyntax/ext/tt/transcribe.rs

@@ -293,8 +293,8 @@ pub fn tt_next_token(r: &mut TtReader) -> TokenAndSpan {
                             // (a) idents can be in lots of places, so it'd be a pain
                             // (b) we actually can, since it's a token.
                             MatchedNonterminal(NtIdent(ref sn, b)) => {
-                                r.cur_span = sp;
-                                r.cur_tok = token::Ident(**sn, b);
+                                r.cur_span = sn.span;
+                                r.cur_tok = token::Ident(sn.node, b);
                                 return ret_val;
                             }
                             MatchedNonterminal(ref other_whole_nt) => {

src/libsyntax/fold.rs

@@ -663,7 +663,8 @@ pub fn noop_fold_interpolated<T: Folder>(nt: token::Nonterminal, fld: &mut T)
         token::NtExpr(expr) => token::NtExpr(fld.fold_expr(expr)),
         token::NtTy(ty) => token::NtTy(fld.fold_ty(ty)),
         token::NtIdent(id, is_mod_name) =>
-            token::NtIdent(Box::new(fld.fold_ident(*id)), is_mod_name),
+            token::NtIdent(Box::new(Spanned::<Ident>{node: fld.fold_ident(id.node), .. *id}),
+                           is_mod_name),
         token::NtMeta(meta_item) => token::NtMeta(fld.fold_meta_item(meta_item)),
         token::NtPath(path) => token::NtPath(Box::new(fld.fold_path(*path))),
         token::NtTT(tt) => token::NtTT(P(fld.fold_tt(&tt))),

src/libsyntax/parse/token.rs

@@ -377,7 +377,7 @@ pub enum Nonterminal {
     NtPat(P<ast::Pat>),
     NtExpr(P<ast::Expr>),
     NtTy(P<ast::Ty>),
-    NtIdent(Box<ast::Ident>, IdentStyle),
+    NtIdent(Box<ast::SpannedIdent>, IdentStyle),
     /// Stuff inside brackets for attributes
     NtMeta(P<ast::MetaItem>),
     NtPath(Box<ast::Path>),

src/libsyntax/print/pprust.rs

@@ -296,7 +296,7 @@ pub fn token_to_string(tok: &Token) -> String {
             token::NtBlock(ref e)       => block_to_string(&**e),
             token::NtStmt(ref e)        => stmt_to_string(&**e),
             token::NtPat(ref e)         => pat_to_string(&**e),
-            token::NtIdent(ref e, _)    => ident_to_string(**e),
+            token::NtIdent(ref e, _)    => ident_to_string(e.node),
             token::NtTT(ref e)          => tt_to_string(&**e),
             token::NtArm(ref e)         => arm_to_string(&*e),
             token::NtImplItem(ref e)    => impl_item_to_string(&**e),

src/test/compile-fail/macro-parameter-span.rs

@@ -0,0 +1,23 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+macro_rules! foo {
+    ($id: ident) => {
+        $id
+    }
+}
+
+// Testing that the error span points to the parameter 'x' in the callsite,
+// not to the macro variable '$id'
+fn main() {
+    foo!(
+        x //~ ERROR unresolved name `x`
+        );
+}