remove unnecessary hir::map imports

src/librustc_ast_lowering/lib.rs

@@ -37,7 +37,6 @@
 use rustc::arena::Arena;
 use rustc::dep_graph::DepGraph;
 use rustc::hir::map::definitions::{DefKey, DefPathData, Definitions};
-use rustc::hir::map::Map;
 use rustc::{bug, span_bug};
 use rustc_ast::ast;
 use rustc_ast::ast::*;
@@ -1460,7 +1459,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         }
 
         impl<'r, 'a, 'v, 'hir> intravisit::Visitor<'v> for ImplTraitLifetimeCollector<'r, 'a, 'hir> {
-            type Map = Map<'v>;
+            type Map = intravisit::ErasedMap<'v>;
 
             fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
                 intravisit::NestedVisitorMap::None

src/librustc_hir/intravisit.rs

@@ -127,6 +127,25 @@ pub trait Map<'hir> {
     fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir>;
 }
 
+/// An erased version of `Map<'hir>`, using dynamic dispatch.
+/// NOTE: This type is effectively only usable with `NestedVisitorMap::None`.
+pub struct ErasedMap<'hir>(&'hir dyn Map<'hir>);
+
+impl<'hir> Map<'hir> for ErasedMap<'hir> {
+    fn body(&self, id: BodyId) -> &'hir Body<'hir> {
+        self.0.body(id)
+    }
+    fn item(&self, id: HirId) -> &'hir Item<'hir> {
+        self.0.item(id)
+    }
+    fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem<'hir> {
+        self.0.trait_item(id)
+    }
+    fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir> {
+        self.0.impl_item(id)
+    }
+}
+
 /// Specifies what nested things a visitor wants to visit. The most
 /// common choice is `OnlyBodies`, which will cause the visitor to
 /// visit fn bodies for fns that it encounters, but skip over nested

src/librustc_lint/builtin.rs

@@ -22,7 +22,6 @@
 //! `late_lint_methods!` invocation in `lib.rs`.
 
 use crate::{EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext};
-use rustc::hir::map::Map;
 use rustc::lint::LintDiagnosticBuilder;
 use rustc::ty::{self, layout::VariantIdx, Ty, TyCtxt};
 use rustc_ast::ast::{self, Expr};
@@ -1071,7 +1070,7 @@ impl TypeAliasBounds {
             err: &'a mut DiagnosticBuilder<'db>,
         }
         impl<'a, 'db, 'v> Visitor<'v> for WalkAssocTypes<'a, 'db> {
-            type Map = Map<'v>;
+            type Map = intravisit::ErasedMap<'v>;
 
             fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
                 intravisit::NestedVisitorMap::None

src/librustc_mir/transform/check_unsafety.rs

@@ -1,4 +1,3 @@
-use rustc::hir::map::Map;
 use rustc::lint::builtin::{SAFE_PACKED_BORROWS, UNUSED_UNSAFE};
 use rustc::mir::visit::{MutatingUseContext, PlaceContext, Visitor};
 use rustc::mir::*;
@@ -451,7 +450,7 @@ struct UnusedUnsafeVisitor<'a> {
 }
 
 impl<'a, 'tcx> intravisit::Visitor<'tcx> for UnusedUnsafeVisitor<'a> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
         intravisit::NestedVisitorMap::None

src/librustc_mir/transform/mod.rs

@@ -1,5 +1,4 @@
 use crate::{shim, util};
-use rustc::hir::map::Map;
 use rustc::mir::{BodyAndCache, ConstQualifs, MirPhase, Promoted};
 use rustc::ty::query::Providers;
 use rustc::ty::steal::Steal;
@@ -86,7 +85,7 @@ fn mir_keys(tcx: TyCtxt<'_>, krate: CrateNum) -> &DefIdSet {
             }
             intravisit::walk_struct_def(self, v)
         }
-        type Map = Map<'tcx>;
+        type Map = intravisit::ErasedMap<'tcx>;
         fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
             NestedVisitorMap::None
         }

src/librustc_mir_build/hair/pattern/check_match.rs

@@ -4,7 +4,6 @@ use super::_match::{expand_pattern, is_useful, MatchCheckCtxt, Matrix, PatStack}
 
 use super::{PatCtxt, PatKind, PatternError};
 
-use rustc::hir::map::Map;
 use rustc::ty::{self, Ty, TyCtxt};
 use rustc_ast::ast::Mutability;
 use rustc_errors::{error_code, struct_span_err, Applicability, DiagnosticBuilder};
@@ -43,7 +42,7 @@ struct MatchVisitor<'a, 'tcx> {
 }
 
 impl<'tcx> Visitor<'tcx> for MatchVisitor<'_, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None
@@ -753,7 +752,7 @@ fn check_legality_of_bindings_in_at_patterns(cx: &MatchVisitor<'_, '_>, pat: &Pa
     }
 
     impl<'v> Visitor<'v> for AtBindingPatternVisitor<'_, '_, '_> {
-        type Map = Map<'v>;
+        type Map = intravisit::ErasedMap<'v>;
 
         fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
             NestedVisitorMap::None

src/librustc_passes/dead.rs

@@ -210,7 +210,7 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
 }
 
 impl<'a, 'tcx> Visitor<'tcx> for MarkSymbolVisitor<'a, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_passes/intrinsicck.rs

@@ -1,4 +1,3 @@
-use rustc::hir::map::Map;
 use rustc::ty::layout::{LayoutError, Pointer, SizeSkeleton, VariantIdx};
 use rustc::ty::query::Providers;
 use rustc::ty::{self, Ty, TyCtxt};
@@ -122,7 +121,7 @@ impl ExprVisitor<'tcx> {
 }
 
 impl Visitor<'tcx> for ItemVisitor<'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None
@@ -139,7 +138,7 @@ impl Visitor<'tcx> for ItemVisitor<'tcx> {
 }
 
 impl Visitor<'tcx> for ExprVisitor<'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_passes/liveness.rs

@@ -1359,7 +1359,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
 // Checking for error conditions
 
 impl<'a, 'tcx> Visitor<'tcx> for Liveness<'a, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_passes/reachable.rs

@@ -5,7 +5,6 @@
 // makes all other generics or inline functions that it references
 // reachable as well.
 
-use rustc::hir::map::Map;
 use rustc::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
 use rustc::middle::privacy;
 use rustc::session::config;
@@ -17,8 +16,7 @@ use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_hir::def_id::{CrateNum, DefId};
-use rustc_hir::intravisit;
-use rustc_hir::intravisit::{NestedVisitorMap, Visitor};
+use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
 use rustc_hir::{HirIdSet, Node};
 use rustc_target::spec::abi::Abi;
@@ -83,7 +81,7 @@ struct ReachableContext<'a, 'tcx> {
 }
 
 impl<'a, 'tcx> Visitor<'tcx> for ReachableContext<'a, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_passes/region.rs

@@ -6,7 +6,6 @@
 //!
 //! [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/borrow_check.html
 
-use rustc::hir::map::Map;
 use rustc::middle::region::*;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
@@ -696,7 +695,7 @@ impl<'tcx> RegionResolutionVisitor<'tcx> {
 }
 
 impl<'tcx> Visitor<'tcx> for RegionResolutionVisitor<'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_passes/upvars.rs

@@ -1,6 +1,5 @@
 //! Upvar (closure capture) collection from cross-body HIR uses of `Res::Local`s.
 
-use rustc::hir::map::Map;
 use rustc::ty::query::Providers;
 use rustc::ty::TyCtxt;
 use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
@@ -44,7 +43,7 @@ struct LocalCollector {
 }
 
 impl Visitor<'tcx> for LocalCollector {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None
@@ -73,7 +72,7 @@ impl CaptureCollector<'_, '_> {
 }
 
 impl Visitor<'tcx> for CaptureCollector<'a, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_passes/weak_lang_items.rs

@@ -4,7 +4,6 @@ use rustc::middle::lang_items;
 use rustc::middle::lang_items::whitelisted;
 use rustc::session::config;
 
-use rustc::hir::map::Map;
 use rustc::ty::TyCtxt;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::struct_span_err;
@@ -85,9 +84,9 @@ impl<'a, 'tcx> Context<'a, 'tcx> {
 }
 
 impl<'a, 'tcx, 'v> Visitor<'v> for Context<'a, 'tcx> {
-    type Map = Map<'v>;
+    type Map = intravisit::ErasedMap<'v>;
 
-    fn nested_visit_map(&mut self) -> NestedVisitorMap<Map<'v>> {
+    fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None
     }
 

src/librustc_privacy/lib.rs

@@ -1447,7 +1447,7 @@ impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
 }
 
 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
-    type Map = Map<'v>;
+    type Map = intravisit::ErasedMap<'v>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_resolve/late/lifetimes.rs

@@ -1123,7 +1123,7 @@ fn extract_labels(ctxt: &mut LifetimeContext<'_, '_>, body: &hir::Body<'_>) {
     gather.visit_body(body);
 
     impl<'v, 'a, 'tcx> Visitor<'v> for GatherLabels<'a, 'tcx> {
-        type Map = Map<'v>;
+        type Map = intravisit::ErasedMap<'v>;
 
         fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
             NestedVisitorMap::None
@@ -2172,7 +2172,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
             }
 
             impl<'a> Visitor<'a> for SelfVisitor<'a> {
-                type Map = Map<'a>;
+                type Map = intravisit::ErasedMap<'a>;
 
                 fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
                     NestedVisitorMap::None
@@ -2263,7 +2263,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
         }
 
         impl<'v, 'a> Visitor<'v> for GatherLifetimes<'a> {
-            type Map = Map<'v>;
+            type Map = intravisit::ErasedMap<'v>;
 
             fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
                 NestedVisitorMap::None
@@ -2852,7 +2852,7 @@ fn insert_late_bound_lifetimes(
     }
 
     impl<'v> Visitor<'v> for ConstrainedCollector {
-        type Map = Map<'v>;
+        type Map = intravisit::ErasedMap<'v>;
 
         fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
             NestedVisitorMap::None
@@ -2895,7 +2895,7 @@ fn insert_late_bound_lifetimes(
     }
 
     impl<'v> Visitor<'v> for AllCollector {
-        type Map = Map<'v>;
+        type Map = intravisit::ErasedMap<'v>;
 
         fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
             NestedVisitorMap::None

src/librustc_trait_selection/traits/error_reporting/suggestions.rs

@@ -1567,7 +1567,7 @@ struct ReturnsVisitor<'v> {
 }
 
 impl<'v> Visitor<'v> for ReturnsVisitor<'v> {
-    type Map = rustc::hir::map::Map<'v>;
+    type Map = hir::intravisit::ErasedMap<'v>;
 
     fn nested_visit_map(&mut self) -> hir::intravisit::NestedVisitorMap<Self::Map> {
         hir::intravisit::NestedVisitorMap::None

src/librustc_typeck/check/compare_method.rs

@@ -1,4 +1,3 @@
-use rustc::hir::map::Map;
 use rustc::ty::error::{ExpectedFound, TypeError};
 use rustc::ty::subst::{InternalSubsts, Subst};
 use rustc::ty::util::ExplicitSelf;
@@ -890,7 +889,7 @@ fn compare_synthetic_generics<'tcx>(
                                     }
                                 }
                             }
-                            type Map = Map<'v>;
+                            type Map = intravisit::ErasedMap<'v>;
                             fn nested_visit_map(
                                 &mut self,
                             ) -> intravisit::NestedVisitorMap<Self::Map>

src/librustc_typeck/check/generator_interior.rs

@@ -4,7 +4,6 @@
 //! types computed here.
 
 use super::FnCtxt;
-use rustc::hir::map::Map;
 use rustc::middle::region::{self, YieldData};
 use rustc::ty::{self, Ty};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
@@ -209,7 +208,7 @@ pub fn resolve_interior<'a, 'tcx>(
 // librustc/middle/region.rs since `expr_count` is compared against the results
 // there.
 impl<'a, 'tcx> Visitor<'tcx> for InteriorVisitor<'a, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_typeck/check/method/suggest.rs

@@ -4,7 +4,6 @@
 use crate::check::FnCtxt;
 use crate::middle::lang_items::FnOnceTraitLangItem;
 use rustc::hir::map as hir_map;
-use rustc::hir::map::Map;
 use rustc::ty::print::with_crate_prefix;
 use rustc::ty::{self, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness};
 use rustc_ast::ast;
@@ -1347,7 +1346,7 @@ impl intravisit::Visitor<'tcx> for UsePlacementFinder<'tcx> {
         }
     }
 
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
         intravisit::NestedVisitorMap::None

src/librustc_typeck/check/mod.rs

@@ -90,7 +90,6 @@ pub mod writeback;
 use crate::astconv::{AstConv, GenericArgCountMismatch, PathSeg};
 use crate::middle::lang_items;
 use rustc::hir::map::blocks::FnLikeNode;
-use rustc::hir::map::Map;
 use rustc::middle::region;
 use rustc::mir::interpret::ConstValue;
 use rustc::session::parse::feature_err;
@@ -1177,7 +1176,7 @@ impl<'a, 'tcx> GatherLocalsVisitor<'a, 'tcx> {
 }
 
 impl<'a, 'tcx> Visitor<'tcx> for GatherLocalsVisitor<'a, 'tcx> {
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None

src/librustc_typeck/check/regionck.rs

@@ -76,7 +76,6 @@ use crate::check::dropck;
 use crate::check::FnCtxt;
 use crate::mem_categorization as mc;
 use crate::middle::region;
-use rustc::hir::map::Map;
 use rustc::ty::adjustment;
 use rustc::ty::subst::{GenericArgKind, SubstsRef};
 use rustc::ty::{self, Ty};
@@ -417,7 +416,7 @@ impl<'a, 'tcx> Visitor<'tcx> for RegionCtxt<'a, 'tcx> {
     // hierarchy, and in particular the relationships between free
     // regions, until regionck, as described in #3238.
 
-    type Map = Map<'tcx>;
+    type Map = intravisit::ErasedMap<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
         NestedVisitorMap::None