Rollup merge of #35090 - michaelwoerister:get-rid-of-id-visitor, r=eddyb

intravisit: Fold functionality of IdVisitor into the regular Visitor.

Author: Manishearth

src/librustc/hir/intravisit.rs

@@ -197,7 +197,7 @@ impl<'ast> Visitor<'ast> for NodeCollector<'ast> {
     fn visit_fn(&mut self, fk: intravisit::FnKind<'ast>, fd: &'ast FnDecl,
                 b: &'ast Block, s: Span, id: NodeId) {
         assert_eq!(self.parent_node, id);
-        intravisit::walk_fn(self, fk, fd, b, s);
+        intravisit::walk_fn(self, fk, fd, b, s, id);
     }
 
     fn visit_block(&mut self, block: &'ast Block) {

src/librustc/hir/map/collector.rs

@@ -1362,9 +1362,9 @@ pub enum ViewPath_ {
 /// TraitRef's appear in impls.
 ///
 /// resolve maps each TraitRef's ref_id to its defining trait; that's all
-/// that the ref_id is for. The impl_id maps to the "self type" of this impl.
-/// If this impl is an ItemImpl, the impl_id is redundant (it could be the
-/// same as the impl's node id).
+/// that the ref_id is for. Note that ref_id's value is not the NodeId of the
+/// trait being referred to but just a unique NodeId that serves as a key
+/// within the DefMap.
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub struct TraitRef {
     pub path: Path,

src/librustc/hir/mod.rs

@@ -45,7 +45,6 @@ use syntax_pos::Span;
 use errors::DiagnosticBuilder;
 use hir;
 use hir::intravisit as hir_visit;
-use hir::intravisit::{IdVisitor, IdVisitingOperation};
 use syntax::visit as ast_visit;
 
 /// Information about the registered lints.
@@ -663,9 +662,11 @@ impl<'a, 'tcx> LateContext<'a, 'tcx> {
     }
 
     fn visit_ids<F>(&mut self, f: F)
-        where F: FnOnce(&mut IdVisitor<LateContext>)
+        where F: FnOnce(&mut IdVisitor)
     {
-        let mut v = IdVisitor::new(self);
+        let mut v = IdVisitor {
+            cx: self
+        };
         f(&mut v);
     }
 }
@@ -779,7 +780,7 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
     fn visit_fn(&mut self, fk: hir_visit::FnKind<'v>, decl: &'v hir::FnDecl,
                 body: &'v hir::Block, span: Span, id: ast::NodeId) {
         run_lints!(self, check_fn, late_passes, fk, decl, body, span, id);
-        hir_visit::walk_fn(self, fk, decl, body, span);
+        hir_visit::walk_fn(self, fk, decl, body, span, id);
         run_lints!(self, check_fn_post, late_passes, fk, decl, body, span, id);
     }
 
@@ -820,7 +821,7 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
 
     fn visit_mod(&mut self, m: &hir::Mod, s: Span, n: ast::NodeId) {
         run_lints!(self, check_mod, late_passes, m, s, n);
-        hir_visit::walk_mod(self, m);
+        hir_visit::walk_mod(self, m, n);
         run_lints!(self, check_mod_post, late_passes, m, s, n);
     }
 
@@ -859,7 +860,7 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
     fn visit_trait_item(&mut self, trait_item: &hir::TraitItem) {
         self.with_lint_attrs(&trait_item.attrs, |cx| {
             run_lints!(cx, check_trait_item, late_passes, trait_item);
-            cx.visit_ids(|v| v.visit_trait_item(trait_item));
+            cx.visit_ids(|v| hir_visit::walk_trait_item(v, trait_item));
             hir_visit::walk_trait_item(cx, trait_item);
             run_lints!(cx, check_trait_item_post, late_passes, trait_item);
         });
@@ -868,7 +869,7 @@ impl<'a, 'tcx, 'v> hir_visit::Visitor<'v> for LateContext<'a, 'tcx> {
     fn visit_impl_item(&mut self, impl_item: &hir::ImplItem) {
         self.with_lint_attrs(&impl_item.attrs, |cx| {
             run_lints!(cx, check_impl_item, late_passes, impl_item);
-            cx.visit_ids(|v| v.visit_impl_item(impl_item));
+            cx.visit_ids(|v| hir_visit::walk_impl_item(v, impl_item));
             hir_visit::walk_impl_item(cx, impl_item);
             run_lints!(cx, check_impl_item_post, late_passes, impl_item);
         });
@@ -1046,16 +1047,30 @@ impl<'a> ast_visit::Visitor for EarlyContext<'a> {
     }
 }
 
+struct IdVisitor<'a, 'b: 'a, 'tcx: 'a+'b> {
+    cx: &'a mut LateContext<'b, 'tcx>
+}
+
 // Output any lints that were previously added to the session.
-impl<'a, 'tcx> IdVisitingOperation for LateContext<'a, 'tcx> {
+impl<'a, 'b, 'tcx, 'v> hir_visit::Visitor<'v> for IdVisitor<'a, 'b, 'tcx> {
+
     fn visit_id(&mut self, id: ast::NodeId) {
-        if let Some(lints) = self.sess().lints.borrow_mut().remove(&id) {
+        if let Some(lints) = self.cx.sess().lints.borrow_mut().remove(&id) {
             debug!("LateContext::visit_id: id={:?} lints={:?}", id, lints);
             for (lint_id, span, msg) in lints {
-                self.span_lint(lint_id.lint, span, &msg[..])
+                self.cx.span_lint(lint_id.lint, span, &msg[..])
             }
         }
     }
+
+    fn visit_trait_item(&mut self, _ti: &hir::TraitItem) {
+        // Do not recurse into trait or impl items automatically. These are
+        // processed separately by calling hir_visit::walk_trait_item()
+    }
+
+    fn visit_impl_item(&mut self, _ii: &hir::ImplItem) {
+        // See visit_trait_item()
+    }
 }
 
 enum CheckLintNameResult {
@@ -1172,7 +1187,6 @@ pub fn check_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     // Visit the whole crate.
     cx.with_lint_attrs(&krate.attrs, |cx| {
-        cx.visit_id(ast::CRATE_NODE_ID);
         cx.visit_ids(|v| {
             hir_visit::walk_crate(v, krate);
         });

src/librustc/lint/context.rs

@@ -44,7 +44,7 @@ use syntax::parse::token::InternedString;
 use syntax_pos::Span;
 use rustc_back::target::Target;
 use hir;
-use hir::intravisit::{IdVisitor, IdVisitingOperation, Visitor};
+use hir::intravisit::Visitor;
 
 pub use self::DefLike::{DlDef, DlField, DlImpl};
 pub use self::NativeLibraryKind::{NativeStatic, NativeFramework, NativeUnknown};
@@ -292,11 +292,6 @@ impl InlinedItem {
             InlinedItem::ImplItem(_, ref ii) => visitor.visit_impl_item(ii),
         }
     }
-
-    pub fn visit_ids<O: IdVisitingOperation>(&self, operation: &mut O) {
-        let mut id_visitor = IdVisitor::new(operation);
-        self.visit(&mut id_visitor);
-    }
 }
 
 // FIXME: find a better place for this?

src/librustc/middle/cstore.rs

@@ -79,7 +79,7 @@ impl<'a, 'tcx> EffectCheckVisitor<'a, 'tcx> {
 
 impl<'a, 'tcx, 'v> Visitor<'v> for EffectCheckVisitor<'a, 'tcx> {
     fn visit_fn(&mut self, fn_kind: FnKind<'v>, fn_decl: &'v hir::FnDecl,
-                block: &'v hir::Block, span: Span, _: ast::NodeId) {
+                block: &'v hir::Block, span: Span, id: ast::NodeId) {
 
         let (is_item_fn, is_unsafe_fn) = match fn_kind {
             FnKind::ItemFn(_, _, unsafety, _, _, _, _) =>
@@ -96,7 +96,7 @@ impl<'a, 'tcx, 'v> Visitor<'v> for EffectCheckVisitor<'a, 'tcx> {
             self.unsafe_context = UnsafeContext::new(SafeContext)
         }
 
-        intravisit::walk_fn(self, fn_kind, fn_decl, block, span);
+        intravisit::walk_fn(self, fn_kind, fn_decl, block, span, id);
 
         self.unsafe_context = old_unsafe_context
     }

src/librustc/middle/effect.rs

@@ -390,7 +390,7 @@ fn visit_fn(ir: &mut IrMaps,
 
     // gather up the various local variables, significant expressions,
     // and so forth:
-    intravisit::walk_fn(&mut fn_maps, fk, decl, body, sp);
+    intravisit::walk_fn(&mut fn_maps, fk, decl, body, sp, id);
 
     // Special nodes and variables:
     // - exit_ln represents the end of the fn, either by return or panic

src/librustc/middle/liveness.rs

@@ -197,7 +197,7 @@ fn borrowck_fn(this: &mut BorrowckCtxt,
                              decl,
                              body);
 
-    intravisit::walk_fn(this, fk, decl, body, sp);
+    intravisit::walk_fn(this, fk, decl, body, sp, id);
 }
 
 fn build_borrowck_dataflow_data<'a, 'tcx>(this: &mut BorrowckCtxt<'a, 'tcx>,

src/librustc_borrowck/borrowck/mod.rs

@@ -34,7 +34,7 @@ use std::iter::{FromIterator, IntoIterator, repeat};
 
 use rustc::hir;
 use rustc::hir::{Pat, PatKind};
-use rustc::hir::intravisit::{self, IdVisitor, IdVisitingOperation, Visitor, FnKind};
+use rustc::hir::intravisit::{self, Visitor, FnKind};
 use rustc_back::slice;
 
 use syntax::ast::{self, DUMMY_NODE_ID, NodeId};
@@ -474,7 +474,7 @@ struct RenamingRecorder<'map> {
     renaming_map: &'map mut FnvHashMap<(NodeId, Span), NodeId>
 }
 
-impl<'map> IdVisitingOperation for RenamingRecorder<'map> {
+impl<'v, 'map> Visitor<'v> for RenamingRecorder<'map> {
     fn visit_id(&mut self, node_id: NodeId) {
         let key = (node_id, self.origin_span);
         self.renaming_map.insert(key, self.substituted_node_id);
@@ -529,9 +529,7 @@ impl<'a, 'tcx> Folder for StaticInliner<'a, 'tcx> {
                 renaming_map: renaming_map,
             };
 
-            let mut id_visitor = IdVisitor::new(&mut renaming_recorder);
-
-            id_visitor.visit_expr(const_expr);
+            renaming_recorder.visit_expr(const_expr);
         }
     }
 }
@@ -1049,7 +1047,7 @@ fn check_fn(cx: &mut MatchCheckCtxt,
         _ => cx.param_env = ParameterEnvironment::for_item(cx.tcx, fn_id),
     }
 
-    intravisit::walk_fn(cx, kind, decl, body, sp);
+    intravisit::walk_fn(cx, kind, decl, body, sp, fn_id);
 
     for input in &decl.inputs {
         check_irrefutable(cx, &input.pat, true);

src/librustc_const_eval/check_match.rs

@@ -385,9 +385,9 @@ mod svh_visitor {
             SawItem.hash(self.st); visit::walk_item(self, i)
         }
 
-        fn visit_mod(&mut self, m: &'a Mod, _s: Span, _n: NodeId) {
+        fn visit_mod(&mut self, m: &'a Mod, _s: Span, n: NodeId) {
             debug!("visit_mod: st={:?}", self.st);
-            SawMod.hash(self.st); visit::walk_mod(self, m)
+            SawMod.hash(self.st); visit::walk_mod(self, m, n)
         }
 
         fn visit_decl(&mut self, d: &'a Decl) {
@@ -406,9 +406,9 @@ mod svh_visitor {
         }
 
         fn visit_fn(&mut self, fk: FnKind<'a>, fd: &'a FnDecl,
-                    b: &'a Block, s: Span, _: NodeId) {
+                    b: &'a Block, s: Span, n: NodeId) {
             debug!("visit_fn: st={:?}", self.st);
-            SawFn.hash(self.st); visit::walk_fn(self, fk, fd, b, s)
+            SawFn.hash(self.st); visit::walk_fn(self, fk, fd, b, s, n)
         }
 
         fn visit_trait_item(&mut self, ti: &'a TraitItem) {