dump refs for path segments in save-analysis

Requires adding path segments to the hir map

Author: Nick Cameron

src/librustc/hir/lowering.rs

@@ -1861,6 +1861,7 @@ impl<'a> LoweringContext<'a> {
         let def = self.expect_full_def(segment.id);
         hir::PathSegment::new(
             segment.ident,
+            Some(segment.id),
             Some(def),
             generic_args,
             infer_types,

src/librustc/hir/map/collector.rs

@@ -392,6 +392,13 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
         });
     }
 
+    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'hir PathSegment) {
+        if let Some(id) = path_segment.id {
+            self.insert(id, Node::PathSegment(path_segment));
+        }
+        intravisit::walk_path_segment(self, path_span, path_segment);
+    }
+
     fn visit_ty(&mut self, ty: &'hir Ty) {
         self.insert(ty.id, Node::Ty(ty));
 

src/librustc/hir/map/mod.rs

@@ -204,7 +204,7 @@ impl<'hir> Map<'hir> {
         if let Some(entry) = self.map[id.as_usize()] {
             self.dep_graph.read_index(entry.dep_node);
         } else {
-            bug!("called `HirMap::read()` with invalid `NodeId`")
+            bug!("called `HirMap::read()` with invalid `NodeId`: {:?}", id)
         }
     }
 
@@ -344,6 +344,7 @@ impl<'hir> Map<'hir> {
             Node::AnonConst(_) |
             Node::Expr(_) |
             Node::Stmt(_) |
+            Node::PathSegment(_) |
             Node::Ty(_) |
             Node::TraitRef(_) |
             Node::Pat(_) |
@@ -884,6 +885,7 @@ impl<'hir> Map<'hir> {
             Some(Node::AnonConst(constant)) => self.body(constant.body).value.span,
             Some(Node::Expr(expr)) => expr.span,
             Some(Node::Stmt(stmt)) => stmt.span,
+            Some(Node::PathSegment(seg)) => seg.ident.span,
             Some(Node::Ty(ty)) => ty.span,
             Some(Node::TraitRef(tr)) => tr.path.span,
             Some(Node::Binding(pat)) => pat.span,
@@ -1098,6 +1100,7 @@ impl<'a> print::State<'a> {
             Node::AnonConst(a)    => self.print_anon_const(&a),
             Node::Expr(a)         => self.print_expr(&a),
             Node::Stmt(a)         => self.print_stmt(&a),
+            Node::PathSegment(_)  => bug!("cannot print PathSegment"),
             Node::Ty(a)           => self.print_type(&a),
             Node::TraitRef(a)     => self.print_trait_ref(&a),
             Node::Binding(a)      |
@@ -1215,6 +1218,9 @@ fn node_id_to_string(map: &Map<'_>, id: NodeId, include_id: bool) -> String {
         Some(Node::Stmt(_)) => {
             format!("stmt {}{}", map.node_to_pretty_string(id), id_str)
         }
+        Some(Node::PathSegment(_)) => {
+            format!("path segment {}{}", map.node_to_pretty_string(id), id_str)
+        }
         Some(Node::Ty(_)) => {
             format!("type {}{}", map.node_to_pretty_string(id), id_str)
         }

src/librustc/hir/mod.rs

@@ -347,6 +347,7 @@ impl fmt::Display for Path {
 pub struct PathSegment {
     /// The identifier portion of this path segment.
     pub ident: Ident,
+    pub id: Option<NodeId>,
     pub def: Option<Def>,
 
     /// Type/lifetime parameters attached to this path. They come in
@@ -368,15 +369,23 @@ impl PathSegment {
     pub fn from_ident(ident: Ident) -> PathSegment {
         PathSegment {
             ident,
+            id: None,
             def: None,
             infer_types: true,
             args: None,
         }
     }
 
-    pub fn new(ident: Ident, def: Option<Def>, args: GenericArgs, infer_types: bool) -> Self {
+    pub fn new(
+        ident: Ident,
+        id: Option<NodeId>,
+        def: Option<Def>,
+        args: GenericArgs,
+        infer_types: bool,
+    ) -> Self {
         PathSegment {
             ident,
+            id,
             def,
             infer_types,
             args: if args.is_empty() {
@@ -2514,6 +2523,7 @@ pub enum Node<'hir> {
     AnonConst(&'hir AnonConst),
     Expr(&'hir Expr),
     Stmt(&'hir Stmt),
+    PathSegment(&'hir PathSegment),
     Ty(&'hir Ty),
     TraitRef(&'hir TraitRef),
     Binding(&'hir Pat),

src/librustc/ich/impls_hir.rs

@@ -174,6 +174,7 @@ impl_stable_hash_for!(struct hir::Path {
 
 impl_stable_hash_for!(struct hir::PathSegment {
     ident -> (ident.name),
+    id,
     def,
     infer_types,
     args

src/librustc_resolve/build_reduced_graph.rs

@@ -392,18 +392,18 @@ impl<'a, 'cl> Resolver<'a, 'cl> {
                     e.emit();
                 }
 
-                for &(ref tree, id) in items {
-                    let prefix = ast::Path {
-                        segments: module_path.iter()
-                            .map(|ident| {
-                                let mut seg = ast::PathSegment::from_ident(ident.0);
-                                seg.id = self.session.next_node_id();
-                                seg
-                            })
-                            .collect(),
-                        span: path.span,
-                    };
+                let prefix = ast::Path {
+                    segments: module_path.into_iter()
+                        .map(|(ident, id)| {
+                            let mut seg = ast::PathSegment::from_ident(ident);
+                            seg.id = id.expect("Missing node id");
+                            seg
+                        })
+                        .collect(),
+                    span: path.span,
+                };
 
+                for &(ref tree, id) in items {
                     self.build_reduced_graph_for_use_tree(
                         root_use_tree,
                         root_id,

src/librustc_resolve/lib.rs

@@ -3614,6 +3614,7 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
 
         for (i, &(ident, id)) in path.iter().enumerate() {
             debug!("resolve_path ident {} {:?}", i, ident);
+
             let is_last = i == path.len() - 1;
             let ns = if is_last { opt_ns.unwrap_or(TypeNS) } else { TypeNS };
             let name = ident.name;
@@ -3713,10 +3714,12 @@ impl<'a, 'crateloader: 'a> Resolver<'a, 'crateloader> {
                     let maybe_assoc = opt_ns != Some(MacroNS) && PathSource::Type.is_expected(def);
                     if let Some(next_module) = binding.module() {
                         module = Some(ModuleOrUniformRoot::Module(next_module));
-                        if !is_last && record_used {
+                        if record_used {
                             if let Some(id) = id {
-                                assert!(id != ast::DUMMY_NODE_ID, "Trying to resolve dummy id");
-                                self.record_def(id, PathResolution::new(def));
+                                if !self.def_map.contains_key(&id) {
+                                    assert!(id != ast::DUMMY_NODE_ID, "Trying to resolve dummy id");
+                                    self.record_def(id, PathResolution::new(def));
+                                }
                             }
                         }
                     } else if def == Def::ToolMod && i + 1 != path.len() {

src/librustc_save_analysis/dump_visitor.rs

@@ -812,9 +812,8 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
         variant: &'l ty::VariantDef,
         base: &'l Option<P<ast::Expr>>,
     ) {
-        self.write_sub_paths_truncated(path);
-
         if let Some(struct_lit_data) = self.save_ctxt.get_expr_data(ex) {
+            self.write_sub_paths_truncated(path);
             down_cast_data!(struct_lit_data, RefData, ex.span);
             if !generated_code(ex.span) {
                 self.dumper.dump_ref(struct_lit_data);
@@ -1232,8 +1231,8 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                         value: String::new(),
                         parent,
                     });
+                    self.write_sub_paths_truncated(&path);
                 }
-                self.write_sub_paths_truncated(&path);
             }
             ast::UseTreeKind::Glob => {
                 let path = ast::Path {
@@ -1268,8 +1267,8 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                         value: names.join(", "),
                         parent,
                     });
+                    self.write_sub_paths(&path);
                 }
-                self.write_sub_paths(&path);
             }
             ast::UseTreeKind::Nested(ref nested_items) => {
                 let prefix = ast::Path {

src/librustc_save_analysis/lib.rs

@@ -632,6 +632,10 @@ impl<'l, 'tcx: 'l> SaveContext<'l, 'tcx> {
             Node::Visibility(&Spanned {
                 node: hir::VisibilityKind::Restricted { ref path, .. }, .. }) => path.def,
 
+            Node::PathSegment(seg) => match seg.def {
+                Some(def) => def,
+                None => HirDef::Err,
+            },
             Node::Expr(&hir::Expr {
                 node: hir::ExprKind::Struct(ref qpath, ..),
                 ..