Calibrate span for method call error messages

Specifically, the method parameter cardinality mismatch or missing
method error message span now gets method itself exactly. It was the
whole expression.

Closes #9390
Closes #13684
Closes #13709

5 files changed, 14 insertions, 7 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 116411c9e05..12a57cacc3a 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -480,7 +480,7 @@ pub enum Expr_ {
     ExprBox(@Expr, @Expr),
     ExprVec(Vec<@Expr>),
     ExprCall(@Expr, Vec<@Expr>),
-    ExprMethodCall(Ident, Vec<P<Ty>>, Vec<@Expr>),
+    ExprMethodCall(SpannedIdent, Vec<P<Ty>>, Vec<@Expr>),
     ExprTup(Vec<@Expr>),
     ExprBinary(BinOp, @Expr, @Expr),
     ExprUnary(UnOp, @Expr),
diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index e1174ea6cc4..d5465303394 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -12,7 +12,7 @@ use abi;
 use ast::{P, Ident};
 use ast;
 use ast_util;
-use codemap::{Span, respan, DUMMY_SP};
+use codemap::{Span, respan, Spanned, DUMMY_SP};
 use ext::base::ExtCtxt;
 use ext::quote::rt::*;
 use fold::Folder;
@@ -548,8 +548,9 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
                         expr: @ast::Expr,
                         ident: ast::Ident,
                         mut args: Vec<@ast::Expr> ) -> @ast::Expr {
+        let id = Spanned { node: ident, span: span };
         args.unshift(expr);
-        self.expr(span, ast::ExprMethodCall(ident, Vec::new(), args))
+        self.expr(span, ast::ExprMethodCall(id, Vec::new(), args))
     }
     fn expr_block(&self, b: P<ast::Block>) -> @ast::Expr {
         self.expr(b.span, ast::ExprBlock(b))
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index 04b289b9fca..d50e425b9a7 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -797,7 +797,7 @@ pub fn noop_fold_expr<T: Folder>(e: @Expr, folder: &mut T) -> @Expr {
         }
         ExprMethodCall(i, ref tps, ref args) => {
             ExprMethodCall(
-                folder.fold_ident(i),
+                respan(i.span, folder.fold_ident(i.node)),
                 tps.iter().map(|&x| folder.fold_ty(x)).collect(),
                 args.iter().map(|&x| folder.fold_expr(x)).collect())
         }
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 8808312bed7..8f011ffab5f 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -1646,7 +1646,11 @@ impl<'a> Parser<'a> {
         ExprCall(f, args)
     }
 
-    fn mk_method_call(&mut self, ident: Ident, tps: Vec<P<Ty>> , args: Vec<@Expr> ) -> ast::Expr_ {
+    fn mk_method_call(&mut self,
+                      ident: ast::SpannedIdent,
+                      tps: Vec<P<Ty>>,
+                      args: Vec<@Expr>)
+                      -> ast::Expr_ {
         ExprMethodCall(ident, tps, args)
     }
 
@@ -1919,6 +1923,7 @@ impl<'a> Parser<'a> {
             if self.eat(&token::DOT) {
                 match self.token {
                   token::IDENT(i, _) => {
+                    let dot = self.last_span.hi;
                     hi = self.span.hi;
                     self.bump();
                     let (_, tys) = if self.eat(&token::MOD_SEP) {
@@ -1940,7 +1945,8 @@ impl<'a> Parser<'a> {
                             hi = self.last_span.hi;
 
                             es.unshift(e);
-                            let nd = self.mk_method_call(i, tys, es);
+                            let id = spanned(dot, hi, i);
+                            let nd = self.mk_method_call(id, tys, es);
                             e = self.mk_expr(lo, hi, nd);
                         }
                         _ => {
diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs
index f768bf22ce0..2f5f1f07fc5 100644
--- a/src/libsyntax/print/pprust.rs
+++ b/src/libsyntax/print/pprust.rs
@@ -1208,7 +1208,7 @@ impl<'a> State<'a> {
                 let base_args = args.slice_from(1);
                 try!(self.print_expr(*args.get(0)));
                 try!(word(&mut self.s, "."));
-                try!(self.print_ident(ident));
+                try!(self.print_ident(ident.node));
                 if tys.len() > 0u {
                     try!(word(&mut self.s, "::<"));
                     try!(self.commasep(Inconsistent, tys.as_slice(),