Merge PatKind::QPath into PatKind::Path in HIR

src/librustc/cfg/construct.rs

@@ -101,7 +101,6 @@ impl<'a, 'tcx> CFGBuilder<'a, 'tcx> {
         match pat.node {
             PatKind::Binding(_, _, None) |
             PatKind::Path(..) |
-            PatKind::QPath(..) |
             PatKind::Lit(..) |
             PatKind::Range(..) |
             PatKind::Wild => {

src/librustc/hir/fold.rs

@@ -930,12 +930,11 @@ pub fn noop_fold_pat<T: Folder>(p: P<Pat>, folder: &mut T) -> P<Pat> {
                     PatKind::TupleStruct(folder.fold_path(pth),
                             pats.move_map(|x| folder.fold_pat(x)), ddpos)
                 }
-                PatKind::Path(pth) => {
-                    PatKind::Path(folder.fold_path(pth))
-                }
-                PatKind::QPath(qself, pth) => {
-                    let qself = QSelf { ty: folder.fold_ty(qself.ty), ..qself };
-                    PatKind::QPath(qself, folder.fold_path(pth))
+                PatKind::Path(opt_qself, pth) => {
+                    let opt_qself = opt_qself.map(|qself| {
+                        QSelf { ty: folder.fold_ty(qself.ty), position: qself.position }
+                    });
+                    PatKind::Path(opt_qself, folder.fold_path(pth))
                 }
                 PatKind::Struct(pth, fields, etc) => {
                     let pth = folder.fold_path(pth);

src/librustc/hir/intravisit.rs

@@ -460,11 +460,10 @@ pub fn walk_pat<'v, V: Visitor<'v>>(visitor: &mut V, pattern: &'v Pat) {
             visitor.visit_path(path, pattern.id);
             walk_list!(visitor, visit_pat, children);
         }
-        PatKind::Path(ref path) => {
-            visitor.visit_path(path, pattern.id);
-        }
-        PatKind::QPath(ref qself, ref path) => {
-            visitor.visit_ty(&qself.ty);
+        PatKind::Path(ref opt_qself, ref path) => {
+            if let Some(ref qself) = *opt_qself {
+                visitor.visit_ty(&qself.ty);
+            }
             visitor.visit_path(path, pattern.id)
         }
         PatKind::Struct(ref path, ref fields, _) => {

src/librustc/hir/lowering.rs

@@ -862,7 +862,8 @@ impl<'a> LoweringContext<'a> {
                                                       respan(pth1.span, pth1.node.name),
                                                       sub.as_ref().map(|x| this.lower_pat(x)))
                             }
-                            _ => hir::PatKind::Path(hir::Path::from_name(pth1.span, pth1.node.name))
+                            _ => hir::PatKind::Path(None, hir::Path::from_name(pth1.span,
+                                                                               pth1.node.name))
                         }
                     })
                 }
@@ -872,15 +873,11 @@ impl<'a> LoweringContext<'a> {
                                               pats.iter().map(|x| self.lower_pat(x)).collect(),
                                               ddpos)
                 }
-                PatKind::Path(None, ref pth) => {
-                    hir::PatKind::Path(self.lower_path(pth))
-                }
-                PatKind::Path(Some(ref qself), ref pth) => {
-                    let qself = hir::QSelf {
-                        ty: self.lower_ty(&qself.ty),
-                        position: qself.position,
-                    };
-                    hir::PatKind::QPath(qself, self.lower_path(pth))
+                PatKind::Path(ref opt_qself, ref path) => {
+                    let opt_qself = opt_qself.map(|qself| {
+                        hir::QSelf { ty: self.lower_ty(&qself.ty), position: qself.position }
+                    });
+                    hir::PatKind::Path(opt_qself, self.lower_path(path))
                 }
                 PatKind::Struct(ref pth, ref fields, etc) => {
                     let pth = self.lower_path(pth);
@@ -1831,7 +1828,7 @@ impl<'a> LoweringContext<'a> {
                 -> P<hir::Pat> {
         let def = self.resolver.resolve_generated_global_path(&path, true);
         let pt = if subpats.is_empty() {
-            hir::PatKind::Path(path)
+            hir::PatKind::Path(None, path)
         } else {
             hir::PatKind::TupleStruct(path, subpats, None)
         };

src/librustc/hir/mod.rs

@@ -487,8 +487,7 @@ impl Pat {
             PatKind::Lit(_) |
             PatKind::Range(_, _) |
             PatKind::Binding(..) |
-            PatKind::Path(..) |
-            PatKind::QPath(_, _) => {
+            PatKind::Path(..) => {
                 true
             }
         }
@@ -538,15 +537,9 @@ pub enum PatKind {
     /// 0 <= position <= subpats.len()
     TupleStruct(Path, HirVec<P<Pat>>, Option<usize>),
 
-    /// A path pattern.
+    /// A possibly qualified path pattern.
     /// Such pattern can be resolved to a unit struct/variant or a constant.
-    Path(Path),
-
-    /// An associated const named using the qualified path `<T>::CONST` or
-    /// `<T as Trait>::CONST`. Associated consts from inherent impls can be
-    /// referred to as simply `T::CONST`, in which case they will end up as
-    /// PatKind::Path, and the resolver will have to sort that out.
-    QPath(QSelf, Path),
+    Path(Option<QSelf>, Path),
 
     /// A tuple pattern `(a, b)`.
     /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.

src/librustc/hir/pat_util.rs

@@ -53,7 +53,7 @@ impl<T: ExactSizeIterator> EnumerateAndAdjustIterator for T {
 
 pub fn pat_is_refutable(dm: &DefMap, pat: &hir::Pat) -> bool {
     match pat.node {
-        PatKind::Lit(_) | PatKind::Range(_, _) | PatKind::QPath(..) => true,
+        PatKind::Lit(_) | PatKind::Range(_, _) | PatKind::Path(Some(..), _) => true,
         PatKind::TupleStruct(..) |
         PatKind::Path(..) |
         PatKind::Struct(..) => {
@@ -69,7 +69,7 @@ pub fn pat_is_refutable(dm: &DefMap, pat: &hir::Pat) -> bool {
 
 pub fn pat_is_const(dm: &DefMap, pat: &hir::Pat) -> bool {
     match pat.node {
-        PatKind::Path(..) | PatKind::QPath(..) => {
+        PatKind::Path(..) => {
             match dm.get(&pat.id).map(|d| d.full_def()) {
                 Some(Def::Const(..)) | Some(Def::AssociatedConst(..)) => true,
                 _ => false

src/librustc/hir/print.rs

@@ -1750,10 +1750,10 @@ impl<'a> State<'a> {
                 }
                 try!(self.pclose());
             }
-            PatKind::Path(ref path) => {
+            PatKind::Path(None, ref path) => {
                 self.print_path(path, true, 0)?;
             }
-            PatKind::QPath(ref qself, ref path) => {
+            PatKind::Path(Some(ref qself), ref path) => {
                 self.print_qpath(path, qself, false)?;
             }
             PatKind::Struct(ref path, ref fields, etc) => {

src/librustc/middle/mem_categorization.rs

@@ -1193,7 +1193,7 @@ impl<'a, 'gcx, 'tcx> MemCategorizationContext<'a, 'gcx, 'tcx> {
             }
           }
 
-          PatKind::Path(..) | PatKind::QPath(..) | PatKind::Binding(_, _, None) |
+          PatKind::Path(..) | PatKind::Binding(_, _, None) |
           PatKind::Lit(..) | PatKind::Range(..) | PatKind::Wild => {
             // always ok
           }

src/librustc_const_eval/check_match.rs

@@ -489,7 +489,7 @@ impl<'map> IdVisitingOperation for RenamingRecorder<'map> {
 impl<'a, 'tcx> Folder for StaticInliner<'a, 'tcx> {
     fn fold_pat(&mut self, pat: P<Pat>) -> P<Pat> {
         return match pat.node {
-            PatKind::Path(..) | PatKind::QPath(..) => {
+            PatKind::Path(..) => {
                 match self.tcx.expect_def(pat.id) {
                     Def::AssociatedConst(did) | Def::Const(did) => {
                         let substs = Some(self.tcx.node_id_item_substs(pat.id).substs);
@@ -583,7 +583,7 @@ fn construct_witness<'a,'tcx>(cx: &MatchCheckCtxt<'a,'tcx>, ctor: &Constructor,
                     PatKind::TupleStruct(def_to_path(cx.tcx, v.did), pats.collect(), None)
                 }
                 VariantKind::Unit => {
-                    PatKind::Path(def_to_path(cx.tcx, v.did))
+                    PatKind::Path(None, def_to_path(cx.tcx, v.did))
                 }
             }
         }
@@ -784,7 +784,7 @@ fn pat_constructors(cx: &MatchCheckCtxt, p: &Pat,
                     left_ty: Ty, max_slice_length: usize) -> Vec<Constructor> {
     let pat = raw_pat(p);
     match pat.node {
-        PatKind::Struct(..) | PatKind::TupleStruct(..) | PatKind::Path(..) | PatKind::QPath(..) =>
+        PatKind::Struct(..) | PatKind::TupleStruct(..) | PatKind::Path(..) =>
             match cx.tcx.expect_def(pat.id) {
                 Def::Variant(_, id) => vec![Variant(id)],
                 Def::Struct(..) | Def::TyAlias(..) | Def::AssociatedTy(..) => vec![Single],
@@ -895,7 +895,7 @@ pub fn specialize<'a, 'b, 'tcx>(
         PatKind::Binding(..) | PatKind::Wild =>
             Some(vec![dummy_pat; arity]),
 
-        PatKind::Path(..) | PatKind::QPath(..) => {
+        PatKind::Path(..) => {
             match cx.tcx.expect_def(pat_id) {
                 Def::Const(..) | Def::AssociatedConst(..) =>
                     span_bug!(pat_span, "const pattern should've \

src/librustc_const_eval/eval.rs

@@ -323,7 +323,7 @@ pub fn const_expr_to_pat<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
         hir::ExprPath(_, ref path) => {
             match tcx.expect_def(expr.id) {
-                Def::Struct(..) | Def::Variant(..) => PatKind::Path(path.clone()),
+                Def::Struct(..) | Def::Variant(..) => PatKind::Path(None, path.clone()),
                 Def::Const(def_id) | Def::AssociatedConst(def_id) => {
                     let substs = Some(tcx.node_id_item_substs(expr.id).substs);
                     let (expr, _ty) = lookup_const_by_id(tcx, def_id, substs).unwrap();

src/librustc_lint/bad_style.rs

@@ -360,7 +360,7 @@ impl LateLintPass for NonUpperCaseGlobals {
 
     fn check_pat(&mut self, cx: &LateContext, p: &hir::Pat) {
         // Lint for constants that look like binding identifiers (#7526)
-        if let PatKind::Path(ref path) = p.node {
+        if let PatKind::Path(None, ref path) = p.node {
             if !path.global && path.segments.len() == 1 && path.segments[0].parameters.is_empty() {
                 if let Def::Const(..) = cx.tcx.expect_def(p.id) {
                     NonUpperCaseGlobals::check_upper_case(cx, "constant in pattern",

src/librustc_mir/hair/cx/pattern.rs

@@ -76,7 +76,7 @@ impl<'patcx, 'cx, 'gcx, 'tcx> PatCx<'patcx, 'cx, 'gcx, 'tcx> {
                 PatternKind::Range { lo: lo, hi: hi }
             },
 
-            PatKind::Path(..) | PatKind::QPath(..) => {
+            PatKind::Path(..) => {
                 match self.cx.tcx.expect_def(pat.id) {
                     Def::Const(def_id) | Def::AssociatedConst(def_id) => {
                         let tcx = self.cx.tcx.global_tcx();

src/librustc_trans/_match.rs

@@ -2003,7 +2003,7 @@ pub fn bind_irrefutable_pat<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
                         cleanup_scope)
                 });
         }
-        PatKind::Path(..) | PatKind::QPath(..) | PatKind::Wild |
+        PatKind::Path(..) | PatKind::Wild |
         PatKind::Lit(..) | PatKind::Range(..) => ()
     }
     return bcx;

src/librustc_trans/debuginfo/create_scope_map.rs

@@ -313,7 +313,7 @@ fn walk_pattern(cx: &CrateContext,
             }
         }
 
-        PatKind::Path(..) | PatKind::QPath(..) => {
+        PatKind::Path(..) => {
             scope_map.insert(pat.id, scope_stack.last().unwrap().scope_metadata);
         }
 

src/librustc_typeck/check/_match.rs

@@ -168,11 +168,9 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
             PatKind::TupleStruct(ref path, ref subpats, ddpos) => {
                 self.check_pat_tuple_struct(pat, path, &subpats, ddpos, expected);
             }
-            PatKind::Path(ref path) => {
-                self.check_pat_path(pat, None, path, expected);
-            }
-            PatKind::QPath(ref qself, ref path) => {
-                self.check_pat_path(pat, Some(self.to_ty(&qself.ty)), path, expected);
+            PatKind::Path(ref opt_qself, ref path) => {
+                let opt_qself_ty = opt_qself.as_ref().map(|qself| self.to_ty(&qself.ty));
+                self.check_pat_path(pat, opt_qself_ty, path, expected);
             }
             PatKind::Struct(ref path, ref fields, etc) => {
                 self.check_pat_struct(pat, path, fields, etc, expected);

src/librustdoc/clean/mod.rs

@@ -2578,9 +2578,9 @@ fn name_from_pat(p: &hir::Pat) -> String {
     match p.node {
         PatKind::Wild => "_".to_string(),
         PatKind::Binding(_, ref p, _) => p.node.to_string(),
-        PatKind::TupleStruct(ref p, _, _) | PatKind::Path(ref p) => path_to_string(p),
-        PatKind::QPath(..) => panic!("tried to get argument name from PatKind::QPath, \
-                                which is not allowed in function arguments"),
+        PatKind::TupleStruct(ref p, _, _) | PatKind::Path(None, ref p) => path_to_string(p),
+        PatKind::Path(..) => panic!("tried to get argument name from qualified PatKind::Path, \
+                                     which is not allowed in function arguments"),
         PatKind::Struct(ref name, ref fields, etc) => {
             format!("{} {{ {}{} }}", path_to_string(name),
                 fields.iter().map(|&Spanned { node: ref fp, .. }|