Auto merge of #43115 - petrochenkov:methlife2, r=eddyb

Store all generic arguments for method calls in AST/HIR

The first part of https://github.com/rust-lang/rust/pull/42492.
Landed separately to start the process of merging libsyntax changes breaking rustfmt, which is not easy these days.

src/Cargo.lock

@@ -578,7 +578,7 @@ dependencies = [
 
 [[package]]
 name = "languageserver-types"
-version = "0.11.0"
+version = "0.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "enum_primitive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1017,14 +1017,14 @@ dependencies = [
  "cargo 0.21.0 (git+https://github.com/rust-lang/cargo)",
  "derive-new 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "languageserver-types 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "languageserver-types 0.11.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "racer 2.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "rls-analysis 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rls-data 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rls-span 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rls-vfs 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustfmt-nightly 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustfmt-nightly 0.1.8 (git+https://github.com/rust-lang-nursery/rustfmt?branch=rustfmt-42492)",
  "serde 1.0.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1474,8 +1474,8 @@ dependencies = [
 
 [[package]]
 name = "rustfmt-nightly"
-version = "0.1.7"
+version = "0.1.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
+source = "git+https://github.com/rust-lang-nursery/rustfmt?branch=rustfmt-42492#7333dfc95b4af5c7283ba03f33c50f108d2be3f5"
 dependencies = [
  "diff 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2067,7 +2067,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "eb2f404fbc66fd9aac13e998248505e7ecb2ad8e44ab6388684c5fb11c6c251c"
 "checksum jobserver 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "4e28adc987f6d0521ef66ad60b055968107b164b3bb3cf3dc8474e0a380474a6"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
-"checksum languageserver-types 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c178b944c3187527293fb9f8a0b0db3c5fb62eb127cacd65296f651a2440f5b1"
+"checksum languageserver-types 0.11.1 (registry+https://github.com/rust-lang/crates.io-index)" = "680aee78c75504fdcb172635a7b7da0dccaafa4c42d935e19576c14b27942362"
 "checksum lazy_static 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "3b37545ab726dd833ec6420aaba8231c5b320814b9029ad585555d2a03e94fbf"
 "checksum libc 0.2.24 (registry+https://github.com/rust-lang/crates.io-index)" = "38f5c2b18a287cf78b4097db62e20f43cace381dc76ae5c0a3073067f78b7ddc"
 "checksum libgit2-sys 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)" = "df18a822100352d9863b302faf6f8f25c0e77f0e60feb40e5dbe1238b7f13b1d"
@@ -2116,7 +2116,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum rls-vfs 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1f19246a0fda45f2fb6eb34addef2a692c044cbf1c90ec7695583450fb5f23e7"
 "checksum rustc-demangle 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "3058a43ada2c2d0b92b3ae38007a2d0fa5e9db971be260e0171408a4ff471c95"
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
-"checksum rustfmt-nightly 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "31ac6fe40a9844ee2de3d51d0be2bbcdb361bad6f3667a02db8c4e2330afbbb5"
+"checksum rustfmt-nightly 0.1.8 (git+https://github.com/rust-lang-nursery/rustfmt?branch=rustfmt-42492)" = "<none>"
 "checksum same-file 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "d931a44fdaa43b8637009e7632a02adc4f2b2e0733c08caa4cf00e8da4a117a7"
 "checksum scoped-tls 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f417c22df063e9450888a7561788e9bd46d3bb3c1466435b4eccb903807f147d"
 "checksum semver 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3fdd61b85a0fa777f7fb7c454b9189b2941b110d1385ce84d7f76efdf1606a85"

src/librustc/hir/intravisit.rs

@@ -944,10 +944,9 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) {
             walk_list!(visitor, visit_expr, arguments);
             visitor.visit_expr(callee_expression)
         }
-        ExprMethodCall(ref name, ref types, ref arguments) => {
+        ExprMethodCall(ref segment, _, ref arguments) => {
-            visitor.visit_name(name.span, name.node);
+            visitor.visit_path_segment(expression.span, segment);
             walk_list!(visitor, visit_expr, arguments);
-            walk_list!(visitor, visit_ty, types);
         }
         ExprBinary(_, ref left_expression, ref right_expression) => {
             visitor.visit_expr(left_expression);

src/librustc/hir/lowering.rs

@@ -1844,10 +1844,10 @@ impl<'a> LoweringContext<'a> {
                 let f = P(self.lower_expr(f));
                 hir::ExprCall(f, args.iter().map(|x| self.lower_expr(x)).collect())
             }
-            ExprKind::MethodCall(i, ref tps, ref args) => {
+            ExprKind::MethodCall(ref seg, ref args) => {
-                let tps = tps.iter().map(|x| self.lower_ty(x)).collect();
+                let hir_seg = self.lower_path_segment(e.span, seg, ParamMode::Optional, 0);
                 let args = args.iter().map(|x| self.lower_expr(x)).collect();
-                hir::ExprMethodCall(respan(i.span, self.lower_ident(i.node)), tps, args)
+                hir::ExprMethodCall(hir_seg, seg.span, args)
             }
             ExprKind::Binary(binop, ref lhs, ref rhs) => {
                 let binop = self.lower_binop(binop);

src/librustc/hir/mod.rs

@@ -972,19 +972,16 @@ pub enum Expr_ {
     /// The first field resolves to the function itself (usually an `ExprPath`),
     /// and the second field is the list of arguments
     ExprCall(P<Expr>, HirVec<Expr>),
-    /// A method call (`x.foo::<Bar, Baz>(a, b, c, d)`)
+    /// A method call (`x.foo::<'static, Bar, Baz>(a, b, c, d)`)
     ///
-    /// The `Spanned<Name>` is the identifier for the method name.
+    /// The `PathSegment`/`Span` represent the method name and its generic arguments
-    /// The vector of `Ty`s are the ascripted type parameters for the method
     /// (within the angle brackets).
-    ///
+    /// The first element of the vector of `Expr`s is the expression that evaluates
-    /// The first element of the vector of `Expr`s is the expression that
+    /// to the object on which the method is being called on (the receiver),
-    /// evaluates to the object on which the method is being called on (the
+    /// and the remaining elements are the rest of the arguments.
-    /// receiver), and the remaining elements are the rest of the arguments.
-    ///
     /// Thus, `x.foo::<Bar, Baz>(a, b, c, d)` is represented as
-    /// `ExprMethodCall(foo, [Bar, Baz], [x, a, b, c, d])`.
+    /// `ExprKind::MethodCall(PathSegment { foo, [Bar, Baz] }, [x, a, b, c, d])`.
-    ExprMethodCall(Spanned<Name>, HirVec<P<Ty>>, HirVec<Expr>),
+    ExprMethodCall(PathSegment, Span, HirVec<Expr>),
     /// A tuple (`(a, b, c ,d)`)
     ExprTup(HirVec<Expr>),
     /// A binary operation (For example: `a + b`, `a * b`)

src/librustc/hir/print.rs

@@ -1188,18 +1188,17 @@ impl<'a> State<'a> {
     }
 
     fn print_expr_method_call(&mut self,
-                              name: Spanned<ast::Name>,
+                              segment: &hir::PathSegment,
-                              tys: &[P<hir::Ty>],
                               args: &[hir::Expr])
                               -> io::Result<()> {
         let base_args = &args[1..];
         self.print_expr(&args[0])?;
         word(&mut self.s, ".")?;
-        self.print_name(name.node)?;
+        self.print_name(segment.name)?;
-        if !tys.is_empty() {
+        if !segment.parameters.lifetimes().is_empty() ||
-            word(&mut self.s, "::<")?;
+                !segment.parameters.types().is_empty() ||
-            self.commasep(Inconsistent, tys, |s, ty| s.print_type(&ty))?;
+                !segment.parameters.bindings().is_empty() {
-            word(&mut self.s, ">")?;
+            self.print_path_parameters(&segment.parameters, true)?;
         }
         self.print_call_post(base_args)
     }
@@ -1254,8 +1253,8 @@ impl<'a> State<'a> {
             hir::ExprCall(ref func, ref args) => {
                 self.print_expr_call(&func, args)?;
             }
-            hir::ExprMethodCall(name, ref tys, ref args) => {
+            hir::ExprMethodCall(ref segment, _, ref args) => {
-                self.print_expr_method_call(name, &tys[..], args)?;
+                self.print_expr_method_call(segment, args)?;
             }
             hir::ExprBinary(op, ref lhs, ref rhs) => {
                 self.print_expr_binary(op, &lhs, &rhs)?;

src/librustc/ich/impls_hir.rs

@@ -626,7 +626,7 @@ impl_stable_hash_for!(enum hir::Expr_ {
     ExprBox(sub),
     ExprArray(subs),
     ExprCall(callee, args),
-    ExprMethodCall(name, ts, args),
+    ExprMethodCall(segment, span, args),
     ExprTup(fields),
     ExprBinary(op, lhs, rhs),
     ExprUnary(op, operand),

src/librustc_passes/ast_validation.rs

@@ -125,6 +125,23 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
             ExprKind::Continue(Some(ident)) => {
                 self.check_label(ident.node, ident.span);
             }
+            ExprKind::MethodCall(ref segment, ..) => {
+                if let Some(ref params) = segment.parameters {
+                    match **params {
+                        PathParameters::AngleBracketed(ref param_data) => {
+                            if !param_data.bindings.is_empty() {
+                                let binding_span = param_data.bindings[0].span;
+                                self.err_handler().span_err(binding_span,
+                                    "type bindings cannot be used in method calls");
+                            }
+                        }
+                        PathParameters::Parenthesized(..) => {
+                            self.err_handler().span_err(expr.span,
+                                "parenthesized parameters cannot be used on method calls");
+                        }
+                    }
+                }
+            }
             _ => {}
         }
 

src/librustc_privacy/lib.rs

@@ -670,10 +670,10 @@ impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
                     return;
                 }
             }
-            hir::ExprMethodCall(name, ..) => {
+            hir::ExprMethodCall(_, span, _) => {
                 // Method calls have to be checked specially.
                 let def_id = self.tables.type_dependent_defs[&expr.id].def_id();
-                self.span = name.span;
+                self.span = span;
                 if self.tcx.type_of(def_id).visit_with(self) {
                     return;
                 }

src/librustc_resolve/lib.rs

@@ -2467,9 +2467,9 @@ impl<'a> Resolver<'a> {
                                                                  path_str, ident.node));
                             return err;
                         }
-                        ExprKind::MethodCall(ident, ..) => {
+                        ExprKind::MethodCall(ref segment, ..) => {
                             err.span_label(parent.span, format!("did you mean `{}::{}(...)`?",
-                                                                 path_str, ident.node));
+                                                                 path_str, segment.identifier));
                             return err;
                         }
                         _ => {}
@@ -3145,15 +3145,13 @@ impl<'a> Resolver<'a> {
             ExprKind::Field(ref subexpression, _) => {
                 self.resolve_expr(subexpression, Some(expr));
             }
-            ExprKind::MethodCall(_, ref types, ref arguments) => {
+            ExprKind::MethodCall(ref segment, ref arguments) => {
                 let mut arguments = arguments.iter();
                 self.resolve_expr(arguments.next().unwrap(), Some(expr));
                 for argument in arguments {
                     self.resolve_expr(argument, None);
                 }
-                for ty in types.iter() {
+                self.visit_path_segment(expr.span, segment);
-                    self.visit_ty(ty);
-                }
             }
 
             ExprKind::Repeat(ref element, ref count) => {
@@ -3185,10 +3183,10 @@ impl<'a> Resolver<'a> {
                 let traits = self.get_traits_containing_item(name.node, ValueNS);
                 self.trait_map.insert(expr.id, traits);
             }
-            ExprKind::MethodCall(name, ..) => {
+            ExprKind::MethodCall(ref segment, ..) => {
                 debug!("(recording candidate traits for expr) recording traits for {}",
                        expr.id);
-                let traits = self.get_traits_containing_item(name.node, ValueNS);
+                let traits = self.get_traits_containing_item(segment.identifier, ValueNS);
                 self.trait_map.insert(expr.id, traits);
             }
             _ => {

src/librustc_typeck/check/method/confirm.rs

@@ -44,15 +44,15 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                           call_expr: &'gcx hir::Expr,
                           unadjusted_self_ty: Ty<'tcx>,
                           pick: probe::Pick<'tcx>,
-                          supplied_method_types: Vec<Ty<'tcx>>)
+                          segment: &hir::PathSegment)
                           -> MethodCallee<'tcx> {
-        debug!("confirm(unadjusted_self_ty={:?}, pick={:?}, supplied_method_types={:?})",
+        debug!("confirm(unadjusted_self_ty={:?}, pick={:?}, generic_args={:?})",
                unadjusted_self_ty,
                pick,
-               supplied_method_types);
+               segment.parameters);
 
         let mut confirm_cx = ConfirmContext::new(self, span, self_expr, call_expr);
-        confirm_cx.confirm(unadjusted_self_ty, pick, supplied_method_types)
+        confirm_cx.confirm(unadjusted_self_ty, pick, segment)
     }
 }
 
@@ -73,7 +73,7 @@ impl<'a, 'gcx, 'tcx> ConfirmContext<'a, 'gcx, 'tcx> {
     fn confirm(&mut self,
                unadjusted_self_ty: Ty<'tcx>,
                pick: probe::Pick<'tcx>,
-               supplied_method_types: Vec<Ty<'tcx>>)
+               segment: &hir::PathSegment)
                -> MethodCallee<'tcx> {
         // Adjust the self expression the user provided and obtain the adjusted type.
         let self_ty = self.adjust_self_ty(unadjusted_self_ty, &pick);
@@ -83,7 +83,7 @@ impl<'a, 'gcx, 'tcx> ConfirmContext<'a, 'gcx, 'tcx> {
 
         // Create substitutions for the method's type parameters.
         let rcvr_substs = self.fresh_receiver_substs(self_ty, &pick);
-        let all_substs = self.instantiate_method_substs(&pick, supplied_method_types, rcvr_substs);
+        let all_substs = self.instantiate_method_substs(&pick, segment, rcvr_substs);
 
         debug!("all_substs={:?}", all_substs);
 
@@ -279,9 +279,14 @@ impl<'a, 'gcx, 'tcx> ConfirmContext<'a, 'gcx, 'tcx> {
 
     fn instantiate_method_substs(&mut self,
                                  pick: &probe::Pick<'tcx>,
-                                 mut supplied_method_types: Vec<Ty<'tcx>>,
+                                 segment: &hir::PathSegment,
                                  substs: &Substs<'tcx>)
                                  -> &'tcx Substs<'tcx> {
+        let supplied_method_types = match segment.parameters {
+            hir::AngleBracketedParameters(ref data) => &data.types,
+            _ => bug!("unexpected generic arguments: {:?}", segment.parameters),
+        };
+
         // Determine the values for the generic parameters of the method.
         // If they were not explicitly supplied, just construct fresh
         // variables.
@@ -312,7 +317,6 @@ impl<'a, 'gcx, 'tcx> ConfirmContext<'a, 'gcx, 'tcx> {
                                          num_method_types))
                     .emit();
             }
-            supplied_method_types = vec![self.tcx.types.err; num_method_types];
         }
 
         // Create subst for early-bound lifetime parameters, combining
@@ -331,10 +335,10 @@ impl<'a, 'gcx, 'tcx> ConfirmContext<'a, 'gcx, 'tcx> {
             let i = def.index as usize;
             if i < substs.len() {
                 substs.type_at(i)
-            } else if supplied_method_types.is_empty() {
+            } else if let Some(ast_ty) = supplied_method_types.get(i - supplied_start) {
-                self.type_var_for_def(self.span, def, cur_substs)
+                self.to_ty(ast_ty)
             } else {
-                supplied_method_types[i - supplied_start]
+                self.type_var_for_def(self.span, def, cur_substs)
             }
         })
     }

src/librustc_typeck/check/method/mod.rs

@@ -130,22 +130,21 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
     /// * `supplied_method_types`: the explicit method type parameters, if any (`T1..Tn`)
     /// * `self_expr`:             the self expression (`foo`)
     pub fn lookup_method(&self,
-                         span: Span,
-                         method_name: ast::Name,
                          self_ty: ty::Ty<'tcx>,
-                         supplied_method_types: Vec<ty::Ty<'tcx>>,
+                         segment: &hir::PathSegment,
+                         span: Span,
                          call_expr: &'gcx hir::Expr,
                          self_expr: &'gcx hir::Expr)
                          -> Result<MethodCallee<'tcx>, MethodError<'tcx>> {
         debug!("lookup(method_name={}, self_ty={:?}, call_expr={:?}, self_expr={:?})",
-               method_name,
+               segment.name,
                self_ty,
                call_expr,
                self_expr);
 
         let mode = probe::Mode::MethodCall;
         let self_ty = self.resolve_type_vars_if_possible(&self_ty);
-        let pick = self.probe_for_name(span, mode, method_name, IsSuggestion(false),
+        let pick = self.probe_for_name(span, mode, segment.name, IsSuggestion(false),
                                        self_ty, call_expr.id)?;
 
         if let Some(import_id) = pick.import_id {
@@ -161,7 +160,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                                call_expr,
                                self_ty,
                                pick,
-                               supplied_method_types))
+                               segment))
     }
 
     /// `lookup_method_in_trait` is used for overloaded operators.

src/librustc_typeck/check/mod.rs

@@ -2771,22 +2771,19 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
     // Checks a method call.
     fn check_method_call(&self,
                          expr: &'gcx hir::Expr,
-                         method_name: Spanned<ast::Name>,
+                         segment: &hir::PathSegment,
+                         span: Span,
                          args: &'gcx [hir::Expr],
-                         tps: &[P<hir::Ty>],
                          expected: Expectation<'tcx>,
                          lvalue_pref: LvaluePreference) -> Ty<'tcx> {
         let rcvr = &args[0];
         let rcvr_t = self.check_expr_with_lvalue_pref(&rcvr, lvalue_pref);
-
         // no need to check for bot/err -- callee does that
-        let expr_t = self.structurally_resolved_type(expr.span, rcvr_t);
+        let rcvr_t = self.structurally_resolved_type(expr.span, rcvr_t);
 
-        let tps = tps.iter().map(|ast_ty| self.to_ty(&ast_ty)).collect::<Vec<_>>();
+        let method = match self.lookup_method(rcvr_t,
-        let method = match self.lookup_method(method_name.span,
+                                              segment,
-                                              method_name.node,
+                                              span,
-                                              expr_t,
-                                              tps,
                                               expr,
                                               rcvr) {
             Ok(method) => {
@@ -2794,10 +2791,10 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 Ok(method)
             }
             Err(error) => {
-                if method_name.node != keywords::Invalid.name() {
+                if segment.name != keywords::Invalid.name() {
-                    self.report_method_error(method_name.span,
+                    self.report_method_error(span,
-                                             expr_t,
+                                             rcvr_t,
-                                             method_name.node,
+                                             segment.name,
                                              Some(rcvr),
                                              error,
                                              Some(args));
@@ -2807,7 +2804,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         };
 
         // Call the generic checker.
-        self.check_method_argument_types(method_name.span, method,
+        self.check_method_argument_types(span, method,
                                          &args[1..],
                                          DontTupleArguments,
                                          expected)
@@ -3735,8 +3732,8 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
           hir::ExprCall(ref callee, ref args) => {
               self.check_call(expr, &callee, args, expected)
           }
-          hir::ExprMethodCall(name, ref tps, ref args) => {
+          hir::ExprMethodCall(ref segment, span, ref args) => {
-              self.check_method_call(expr, name, args, &tps[..], expected, lvalue_pref)
+              self.check_method_call(expr, segment, span, args, expected, lvalue_pref)
           }
           hir::ExprCast(ref e, ref t) => {
             // Find the type of `e`. Supply hints based on the type we are casting to,

src/libsyntax/ast.rs

@@ -848,19 +848,16 @@ pub enum ExprKind {
     /// The first field resolves to the function itself,
     /// and the second field is the list of arguments
     Call(P<Expr>, Vec<P<Expr>>),
-    /// A method call (`x.foo::<Bar, Baz>(a, b, c, d)`)
+    /// A method call (`x.foo::<'static, Bar, Baz>(a, b, c, d)`)
     ///
-    /// The `SpannedIdent` is the identifier for the method name.
+    /// The `PathSegment` represents the method name and its generic arguments
-    /// The vector of `Ty`s are the ascripted type parameters for the method
     /// (within the angle brackets).
-    ///
     /// The first element of the vector of `Expr`s is the expression that evaluates
     /// to the object on which the method is being called on (the receiver),
     /// and the remaining elements are the rest of the arguments.
-    ///
     /// Thus, `x.foo::<Bar, Baz>(a, b, c, d)` is represented as
-    /// `ExprKind::MethodCall(foo, [Bar, Baz], [x, a, b, c, d])`.
+    /// `ExprKind::MethodCall(PathSegment { foo, [Bar, Baz] }, [x, a, b, c, d])`.
-    MethodCall(SpannedIdent, Vec<P<Ty>>, Vec<P<Expr>>),
+    MethodCall(PathSegment, Vec<P<Expr>>),
     /// A tuple (`(a, b, c ,d)`)
     Tup(Vec<P<Expr>>),
     /// A binary operation (For example: `a + b`, `a * b`)

src/libsyntax/ext/build.rs

@@ -673,9 +673,8 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
                         expr: P<ast::Expr>,
                         ident: ast::Ident,
                         mut args: Vec<P<ast::Expr>> ) -> P<ast::Expr> {
-        let id = Spanned { node: ident, span: span };
         args.insert(0, expr);
-        self.expr(span, ast::ExprKind::MethodCall(id, Vec::new(), args))
+        self.expr(span, ast::ExprKind::MethodCall(ast::PathSegment::from_ident(ident, span), args))
     }
     fn expr_block(&self, b: P<ast::Block>) -> P<ast::Expr> {
         self.expr(b.span, ast::ExprKind::Block(b))

src/libsyntax/fold.rs

@@ -1151,10 +1151,15 @@ pub fn noop_fold_expr<T: Folder>(Expr {id, node, span, attrs}: Expr, folder: &mu
                 ExprKind::Call(folder.fold_expr(f),
                          folder.fold_exprs(args))
             }
-            ExprKind::MethodCall(i, tps, args) => {
+            ExprKind::MethodCall(seg, args) => {
                 ExprKind::MethodCall(
-                    respan(folder.new_span(i.span), folder.fold_ident(i.node)),
+                    PathSegment {
-                    tps.move_map(|x| folder.fold_ty(x)),
+                        identifier: folder.fold_ident(seg.identifier),
+                        span: folder.new_span(seg.span),
+                        parameters: seg.parameters.map(|ps| {
+                            ps.map(|ps| folder.fold_path_parameters(ps))
+                        }),
+                    },
                     folder.fold_exprs(args))
             }
             ExprKind::Binary(binop, lhs, rhs) => {

src/libsyntax/parse/parser.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use abi::{self, Abi};
-use ast::{AttrStyle, BareFnTy};
+use ast::{AngleBracketedParameterData, AttrStyle, BareFnTy};
 use ast::{RegionTyParamBound, TraitTyParamBound, TraitBoundModifier};
 use ast::Unsafety;
 use ast::{Mod, Arg, Arm, Attribute, BindingMode, TraitItemKind};
@@ -1831,11 +1831,7 @@ impl<'a> Parser<'a> {
             let parameters = if parse_generics && self.eat_lt() {
                 let (lifetimes, types, bindings) = self.parse_generic_args()?;
                 self.expect_gt()?;
-                ast::AngleBracketedParameterData {
+                AngleBracketedParameterData { lifetimes, types, bindings }.into()
-                    lifetimes: lifetimes,
-                    types: types,
-                    bindings: bindings,
-                }.into()
             } else if self.eat(&token::OpenDelim(token::Paren)) {
                 let lo = self.prev_span;
 
@@ -1898,11 +1894,7 @@ impl<'a> Parser<'a> {
                 segments.push(PathSegment {
                     identifier: identifier,
                     span: ident_span,
-                    parameters: ast::AngleBracketedParameterData {
+                    parameters: AngleBracketedParameterData { lifetimes, types, bindings }.into(),
-                        lifetimes: lifetimes,
-                        types: types,
-                        bindings: bindings,
-                    }.into(),
                 });
 
                 // Consumed `a::b::<T,U>`, check for `::` before proceeding
@@ -2023,14 +2015,6 @@ impl<'a> Parser<'a> {
         ExprKind::Call(f, args)
     }
 
-    fn mk_method_call(&mut self,
-                      ident: ast::SpannedIdent,
-                      tps: Vec<P<Ty>>,
-                      args: Vec<P<Expr>>)
-                      -> ast::ExprKind {
-        ExprKind::MethodCall(ident, tps, args)
-    }
-
     pub fn mk_index(&mut self, expr: P<Expr>, idx: P<Expr>) -> ast::ExprKind {
         ExprKind::Index(expr, idx)
     }
@@ -2460,7 +2444,7 @@ impl<'a> Parser<'a> {
     // parsing into an expression.
     fn parse_dot_suffix(&mut self, ident: Ident, ident_span: Span, self_value: P<Expr>, lo: Span)
                         -> PResult<'a, P<Expr>> {
-        let (_, tys, bindings) = if self.eat(&token::ModSep) {
+        let (lifetimes, types, bindings) = if self.eat(&token::ModSep) {
             self.expect_lt()?;
             let args = self.parse_generic_args()?;
             self.expect_gt()?;
@@ -2469,11 +2453,6 @@ impl<'a> Parser<'a> {
             (Vec::new(), Vec::new(), Vec::new())
         };
 
-        if !bindings.is_empty() {
-            let prev_span = self.prev_span;
-            self.span_err(prev_span, "type bindings are only permitted on trait paths");
-        }
-
         Ok(match self.token {
             // expr.f() method call.
             token::OpenDelim(token::Paren) => {
@@ -2486,17 +2465,20 @@ impl<'a> Parser<'a> {
                 let hi = self.prev_span;
 
                 es.insert(0, self_value);
-                let id = respan(ident_span.to(ident_span), ident);
+                let seg = PathSegment {
-                let nd = self.mk_method_call(id, tys, es);
+                    identifier: ident,
-                self.mk_expr(lo.to(hi), nd, ThinVec::new())
+                    span: ident_span.to(ident_span),
+                    parameters: AngleBracketedParameterData { lifetimes, types, bindings }.into(),
+                };
+                self.mk_expr(lo.to(hi), ExprKind::MethodCall(seg, es), ThinVec::new())
             }
             // Field access.
             _ => {
-                if !tys.is_empty() {
+                if let Some(generic_arg_span) = lifetimes.get(0).map(|x| x.span).or_else(||
-                    let prev_span = self.prev_span;
+                                                types.get(0).map(|x| x.span)).or_else(||
-                    self.span_err(prev_span,
+                                                bindings.get(0).map(|x| x.span)) {
-                                  "field expressions may not \
+                    self.span_err(generic_arg_span,
-                                   have type parameters");
+                                  "field expressions may not have generic arguments");
                 }
 
                 let id = respan(ident_span.to(ident_span), ident);

src/libsyntax/print/pprust.rs

@@ -1951,18 +1951,14 @@ impl<'a> State<'a> {
     }
 
     fn print_expr_method_call(&mut self,
-                              ident: ast::SpannedIdent,
+                              segment: &ast::PathSegment,
-                              tys: &[P<ast::Ty>],
                               args: &[P<ast::Expr>]) -> io::Result<()> {
         let base_args = &args[1..];
         self.print_expr(&args[0])?;
         word(&mut self.s, ".")?;
-        self.print_ident(ident.node)?;
+        self.print_ident(segment.identifier)?;
-        if !tys.is_empty() {
+        if let Some(ref parameters) = segment.parameters {
-            word(&mut self.s, "::<")?;
+            self.print_path_parameters(parameters, true)?;
-            self.commasep(Inconsistent, tys,
-                          |s, ty| s.print_type(ty))?;
-            word(&mut self.s, ">")?;
         }
         self.print_call_post(base_args)
     }
@@ -2041,8 +2037,8 @@ impl<'a> State<'a> {
             ast::ExprKind::Call(ref func, ref args) => {
                 self.print_expr_call(func, &args[..])?;
             }
-            ast::ExprKind::MethodCall(ident, ref tys, ref args) => {
+            ast::ExprKind::MethodCall(ref segment, ref args) => {
-                self.print_expr_method_call(ident, &tys[..], &args[..])?;
+                self.print_expr_method_call(segment, &args[..])?;
             }
             ast::ExprKind::Binary(op, ref lhs, ref rhs) => {
                 self.print_expr_binary(op, lhs, rhs)?;

src/libsyntax/visit.rs

@@ -674,9 +674,8 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
             visitor.visit_expr(callee_expression);
             walk_list!(visitor, visit_expr, arguments);
         }
-        ExprKind::MethodCall(ref ident, ref types, ref arguments) => {
+        ExprKind::MethodCall(ref segment, ref arguments) => {
-            visitor.visit_ident(ident.span, ident.node);
+            visitor.visit_path_segment(expression.span, segment);
-            walk_list!(visitor, visit_ty, types);
             walk_list!(visitor, visit_expr, arguments);
         }
         ExprKind::Binary(_, ref left_expression, ref right_expression) => {

src/test/compile-fail/method-call-type-binding.rs

@@ -0,0 +1,13 @@
+// Copyright 2017 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.
+
+fn main() {
+    0.clone::<T = u8>(); //~ ERROR type bindings cannot be used in method calls
+}

src/test/parse-fail/type-parameters-in-field-exprs.rs

@@ -21,5 +21,5 @@ fn main() {
         y: 2,
     };
     f.x::<isize>;
-    //~^ ERROR field expressions may not have type parameters
+    //~^ ERROR field expressions may not have generic arguments
 }

src/tools/rls

@@ -1 +1 @@
-Subproject commit 4c0a8b63d61942349c18727409b2a600446e02d6
+Subproject commit 70b89fdd7e5e77a3b88fc68982861d39d155be29