From fc67d8fac48d48bcdeaab1c8e0a2770e0f246247 Mon Sep 17 00:00:00 2001
From: Nick Cameron <ncameron@mozilla.com>
Date: Fri, 31 Aug 2018 12:01:26 +1200
Subject: [PATCH] Give each PathSegment a NodeId

---
 src/libsyntax/ast.rs          | 10 ++++++++--
 src/libsyntax/ext/build.rs    |  8 ++++++--
 src/libsyntax/fold.rs         |  4 +++-
 src/libsyntax/parse/parser.rs |  4 ++--
 4 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 9ed628e2ed33..7548c2988547 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -129,6 +129,8 @@ pub struct PathSegment {
     /// The identifier portion of this path segment.
     pub ident: Ident,
 
+    pub id: NodeId,
+
     /// Type/lifetime parameters attached to this path. They come in
     /// two flavors: `Path<A,B,C>` and `Path(A,B) -> C`.
     /// `None` means that no parameter list is supplied (`Path`),
@@ -140,10 +142,14 @@ pub struct PathSegment {
 
 impl PathSegment {
     pub fn from_ident(ident: Ident) -> Self {
-        PathSegment { ident, args: None }
+        PathSegment { ident, id: DUMMY_NODE_ID, args: None }
     }
     pub fn crate_root(span: Span) -> Self {
-        PathSegment::from_ident(Ident::new(keywords::CrateRoot.name(), span))
+        PathSegment {
+            ident: Ident::new(keywords::CrateRoot.name(), span),
+            id: CRATE_NODE_ID,
+            args: None,
+        }
     }
 }
 
diff --git a/src/libsyntax/ext/build.rs b/src/libsyntax/ext/build.rs
index 6210003a40da..7928ec1606b1 100644
--- a/src/libsyntax/ext/build.rs
+++ b/src/libsyntax/ext/build.rs
@@ -329,7 +329,11 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         } else {
             None
         };
-        segments.push(ast::PathSegment { ident: last_ident.with_span_pos(span), args });
+        segments.push(ast::PathSegment {
+            ident: last_ident.with_span_pos(span),
+            id: ast::DUMMY_NODE_ID,
+            args,
+        });
         let mut path = ast::Path { span, segments };
         if global {
             if let Some(seg) = path.make_root() {
@@ -366,7 +370,7 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         } else {
             None
         };
-        path.segments.push(ast::PathSegment { ident, args });
+        path.segments.push(ast::PathSegment { ident, id: ast::DUMMY_NODE_ID, args });
 
         (ast::QSelf {
             ty: self_type,
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index 18d5970462f6..bec193548e17 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -468,8 +468,9 @@ pub fn noop_fold_usize<T: Folder>(i: usize, _: &mut T) -> usize {
 
 pub fn noop_fold_path<T: Folder>(Path { segments, span }: Path, fld: &mut T) -> Path {
     Path {
-        segments: segments.move_map(|PathSegment { ident, args }| PathSegment {
+        segments: segments.move_map(|PathSegment { ident, id, args }| PathSegment {
             ident: fld.fold_ident(ident),
+            id: fld.new_id(id),
             args: args.map(|args| args.map(|args| fld.fold_generic_args(args))),
         }),
         span: fld.new_span(span)
@@ -1234,6 +1235,7 @@ pub fn noop_fold_expr<T: Folder>(Expr {id, node, span, attrs}: Expr, folder: &mu
                 ExprKind::MethodCall(
                     PathSegment {
                         ident: folder.fold_ident(seg.ident),
+                        id: folder.new_id(seg.id),
                         args: seg.args.map(|args| {
                             args.map(|args| folder.fold_generic_args(args))
                         }),
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 9c47589a0bd2..619a53e1c7c9 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -2134,10 +2134,10 @@ impl<'a> Parser<'a> {
                 ParenthesisedArgs { inputs, output, span }.into()
             };
 
-            PathSegment { ident, args }
+            PathSegment { ident, args, id: ast::DUMMY_NODE_ID }
         } else {
             // Generic arguments are not found.
-            PathSegment::from_ident(ident)
+            PathSegment::from_ident(ident,)
         })
     }