Squash Span into SourceInfo and rename enum and its inner types

src/librustc/mir/visit.rs

@@ -211,7 +211,7 @@ fn visit_source_info(&mut self,
 
             fn visit_ty(&mut self,
                         ty: & $($mutability)* Ty<'tcx>,
-                        _: PositionalInfo) {
+                        _: Lookup) {
                 self.super_ty(ty);
             }
 
@@ -269,7 +269,11 @@ fn super_mir(&mut self,
                     self.visit_visibility_scope_data(scope);
                 }
 
-                self.visit_ty(&$($mutability)* mir.return_ty, PositionalInfo::Span(mir.span));
+                let lookup = Lookup::Src(SourceInfo {
+                    span: mir.span,
+                    scope: ARGUMENT_VISIBILITY_SCOPE,
+                });
+                self.visit_ty(&$($mutability)* mir.return_ty, lookup);
 
                 for local_decl in &$($mutability)* mir.local_decls {
                     self.visit_local_decl(local_decl);
@@ -388,7 +392,7 @@ fn super_terminator_kind(&mut self,
                                                 ref values,
                                                 ref targets } => {
                         self.visit_operand(discr, source_location);
-                        self.visit_ty(switch_ty, PositionalInfo::Location(source_location));
+                        self.visit_ty(switch_ty, Lookup::Loc(source_location));
                         for value in &values[..] {
                             self.visit_const_int(value, source_location);
                         }
@@ -492,7 +496,7 @@ fn super_rvalue(&mut self,
                                  ref $($mutability)* operand,
                                  ref $($mutability)* ty) => {
                         self.visit_operand(operand, location);
-                        self.visit_ty(ty, PositionalInfo::Location(location));
+                        self.visit_ty(ty, Lookup::Loc(location));
                     }
 
                     Rvalue::BinaryOp(_bin_op,
@@ -514,7 +518,7 @@ fn super_rvalue(&mut self,
                     }
 
                     Rvalue::NullaryOp(_op, ref $($mutability)* ty) => {
-                        self.visit_ty(ty, PositionalInfo::Location(location));
+                        self.visit_ty(ty, Lookup::Loc(location));
                     }
 
                     Rvalue::Aggregate(ref $($mutability)* kind,
@@ -522,7 +526,7 @@ fn super_rvalue(&mut self,
                         let kind = &$($mutability)* **kind;
                         match *kind {
                             AggregateKind::Array(ref $($mutability)* ty) => {
-                                self.visit_ty(ty, PositionalInfo::Location(location));
+                                self.visit_ty(ty, Lookup::Loc(location));
                             }
                             AggregateKind::Tuple => {
                             }
@@ -584,7 +588,7 @@ fn super_static(&mut self,
                     ref $($mutability)* ty,
                 } = *static_;
                 self.visit_def_id(def_id, location);
-                self.visit_ty(ty, PositionalInfo::Location(location));
+                self.visit_ty(ty, Lookup::Loc(location));
             }
 
             fn super_projection(&mut self,
@@ -614,7 +618,7 @@ fn super_projection_elem(&mut self,
                     ProjectionElem::Subslice { from: _, to: _ } => {
                     }
                     ProjectionElem::Field(_field, ref $($mutability)* ty) => {
-                        self.visit_ty(ty, PositionalInfo::Location(location));
+                        self.visit_ty(ty, Lookup::Loc(location));
                     }
                     ProjectionElem::Index(ref $($mutability)* operand) => {
                         self.visit_operand(operand, location);
@@ -638,7 +642,7 @@ fn super_local_decl(&mut self,
                     is_user_variable: _,
                 } = *local_decl;
 
-                self.visit_ty(ty, PositionalInfo::SourceInfo(*source_info));
+                self.visit_ty(ty, Lookup::Src(*source_info));
                 self.visit_source_info(source_info);
             }
 
@@ -661,7 +665,7 @@ fn super_constant(&mut self,
                 } = *constant;
 
                 self.visit_span(span);
-                self.visit_ty(ty, PositionalInfo::Location(location));
+                self.visit_ty(ty, Lookup::Loc(location));
                 self.visit_literal(literal, location);
             }
 
@@ -737,10 +741,9 @@ fn visit_location(&mut self, mir: & $($mutability)* Mir<'tcx>, location: Locatio
 make_mir_visitor!(Visitor,);
 make_mir_visitor!(MutVisitor,mut);
 
-pub enum PositionalInfo {
-    Location(Location),
-    SourceInfo(SourceInfo),
-    Span(Span),
+pub enum Lookup {
+    Loc(Location),
+    Src(SourceInfo),
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]

src/librustc_mir/build/mod.rs

@@ -17,7 +17,7 @@
 use rustc::middle::region::CodeExtent;
 use rustc::mir::*;
 use rustc::mir::transform::MirSource;
-use rustc::mir::visit::{MutVisitor, PositionalInfo};
+use rustc::mir::visit::{MutVisitor, Lookup};
 use rustc::ty::{self, Ty, TyCtxt};
 use rustc::ty::subst::Substs;
 use rustc::util::nodemap::NodeMap;
@@ -143,7 +143,7 @@ struct GlobalizeMir<'a, 'gcx: 'a> {
 }
 
 impl<'a, 'gcx: 'tcx, 'tcx> MutVisitor<'tcx> for GlobalizeMir<'a, 'gcx> {
-    fn visit_ty(&mut self, ty: &mut Ty<'tcx>, _: PositionalInfo) {
+    fn visit_ty(&mut self, ty: &mut Ty<'tcx>, _: Lookup) {
         if let Some(lifted) = self.tcx.lift(ty) {
             *ty = lifted;
         } else {

src/librustc_mir/transform/erase_regions.rs

@@ -15,7 +15,7 @@
 use rustc::ty::subst::Substs;
 use rustc::ty::{Ty, TyCtxt, ClosureSubsts};
 use rustc::mir::*;
-use rustc::mir::visit::{MutVisitor, PositionalInfo};
+use rustc::mir::visit::{MutVisitor, Lookup};
 use rustc::mir::transform::{MirPass, MirSource};
 
 struct EraseRegionsVisitor<'a, 'tcx: 'a> {
@@ -31,7 +31,7 @@ pub fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>) -> Self {
 }
 
 impl<'a, 'tcx> MutVisitor<'tcx> for EraseRegionsVisitor<'a, 'tcx> {
-    fn visit_ty(&mut self, ty: &mut Ty<'tcx>, _: PositionalInfo) {
+    fn visit_ty(&mut self, ty: &mut Ty<'tcx>, _: Lookup) {
         let old_ty = *ty;
         *ty = self.tcx.erase_regions(&old_ty);
     }