Auto merge of #51072 - petrochenkov:ifield, r=eddyb

Use `Ident`s for fields in HIR

Continuation of #49718, part of #49300

Author: bors

src/doc/unstable-book/src/language-features/plugin.md

@@ -208,7 +208,7 @@ impl LintPass for Pass {
 
 impl EarlyLintPass for Pass {
     fn check_item(&mut self, cx: &EarlyContext, it: &ast::Item) {
-        if it.ident.name.as_str() == "lintme" {
+        if it.ident.as_str() == "lintme" {
             cx.span_lint(TEST_LINT, it.span, "item is named 'lintme'");
         }
     }

src/libproc_macro/lib.rs

@@ -1214,14 +1214,14 @@ impl TokenTree {
             SingleQuote => op!('\''),
 
             Ident(ident, false) => {
-                tt!(self::Ident::new(&ident.name.as_str(), Span(span)))
+                tt!(self::Ident::new(&ident.as_str(), Span(span)))
             }
             Ident(ident, true) => {
-                tt!(self::Ident::new_raw(&ident.name.as_str(), Span(span)))
+                tt!(self::Ident::new_raw(&ident.as_str(), Span(span)))
             }
             Lifetime(ident) => {
                 let ident = ident.without_first_quote();
-                stack.push(tt!(self::Ident::new(&ident.name.as_str(), Span(span))));
+                stack.push(tt!(self::Ident::new(&ident.as_str(), Span(span))));
                 tt!(Punct::new('\'', Spacing::Joint))
             }
             Literal(lit, suffix) => tt!(self::Literal { lit, suffix, span: Span(span) }),

src/librustc/hir/intravisit.rs

@@ -42,7 +42,7 @@
 //! example generator inference, and possibly also HIR borrowck.
 
 use rustc_target::spec::abi::Abi;
-use syntax::ast::{NodeId, CRATE_NODE_ID, Name, Attribute};
+use syntax::ast::{NodeId, CRATE_NODE_ID, Ident, Name, Attribute};
 use syntax_pos::Span;
 use hir::*;
 use hir::def::Def;
@@ -248,6 +248,9 @@ pub trait Visitor<'v> : Sized {
     fn visit_name(&mut self, _span: Span, _name: Name) {
         // Nothing to do.
     }
+    fn visit_ident(&mut self, ident: Ident) {
+        walk_ident(self, ident)
+    }
     fn visit_mod(&mut self, m: &'v Mod, _s: Span, n: NodeId) {
         walk_mod(self, m, n)
     }
@@ -413,6 +416,10 @@ pub fn walk_local<'v, V: Visitor<'v>>(visitor: &mut V, local: &'v Local) {
     walk_list!(visitor, visit_ty, &local.ty);
 }
 
+pub fn walk_ident<'v, V: Visitor<'v>>(visitor: &mut V, ident: Ident) {
+    visitor.visit_name(ident.span, ident.name);
+}
+
 pub fn walk_label<'v, V: Visitor<'v>>(visitor: &mut V, label: &'v Label) {
     visitor.visit_name(label.span, label.name);
 }
@@ -662,7 +669,7 @@ pub fn walk_pat<'v, V: Visitor<'v>>(visitor: &mut V, pattern: &'v Pat) {
             visitor.visit_qpath(qpath, pattern.id, pattern.span);
             for field in fields {
                 visitor.visit_id(field.node.id);
-                visitor.visit_name(field.span, field.node.name);
+                visitor.visit_ident(field.node.ident);
                 visitor.visit_pat(&field.node.pat)
             }
         }
@@ -915,7 +922,7 @@ pub fn walk_struct_def<'v, V: Visitor<'v>>(visitor: &mut V, struct_definition: &
 pub fn walk_struct_field<'v, V: Visitor<'v>>(visitor: &mut V, struct_field: &'v StructField) {
     visitor.visit_id(struct_field.id);
     visitor.visit_vis(&struct_field.vis);
-    visitor.visit_name(struct_field.span, struct_field.name);
+    visitor.visit_ident(struct_field.ident);
     visitor.visit_ty(&struct_field.ty);
     walk_list!(visitor, visit_attribute, &struct_field.attrs);
 }
@@ -970,7 +977,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) {
             visitor.visit_qpath(qpath, expression.id, expression.span);
             for field in fields {
                 visitor.visit_id(field.id);
-                visitor.visit_name(field.name.span, field.name.node);
+                visitor.visit_ident(field.ident);
                 visitor.visit_expr(&field.expr)
             }
             walk_list!(visitor, visit_expr, optional_base);
@@ -1035,9 +1042,9 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) {
             visitor.visit_expr(right_expression);
             visitor.visit_expr(left_expression)
         }
-        ExprField(ref subexpression, ref name) => {
+        ExprField(ref subexpression, ident) => {
             visitor.visit_expr(subexpression);
-            visitor.visit_name(name.span, name.node);
+            visitor.visit_ident(ident);
         }
         ExprIndex(ref main_expression, ref index_expression) => {
             visitor.visit_expr(main_expression);

src/librustc/hir/lowering.rs

@@ -2072,11 +2072,11 @@ impl<'a> LoweringContext<'a> {
         hir::StructField {
             span: f.span,
             id: self.lower_node_id(f.id).node_id,
-            name: self.lower_ident(match f.ident {
+            ident: match f.ident {
                 Some(ident) => ident,
                 // FIXME(jseyfried) positional field hygiene
                 None => Ident::new(Symbol::intern(&index.to_string()), f.span),
-            }),
+            },
             vis: self.lower_visibility(&f.vis, None),
             ty: self.lower_ty(&f.ty, ImplTraitContext::Disallowed),
             attrs: self.lower_attrs(&f.attrs),
@@ -2086,7 +2086,7 @@ impl<'a> LoweringContext<'a> {
     fn lower_field(&mut self, f: &Field) -> hir::Field {
         hir::Field {
             id: self.next_id().node_id,
-            name: respan(f.ident.span, self.lower_ident(f.ident)),
+            ident: f.ident,
             expr: P(self.lower_expr(&f.expr)),
             span: f.span,
             is_shorthand: f.is_shorthand,
@@ -2848,7 +2848,7 @@ impl<'a> LoweringContext<'a> {
                         span: f.span,
                         node: hir::FieldPat {
                             id: self.next_id().node_id,
-                            name: self.lower_ident(f.node.ident),
+                            ident: f.node.ident,
                             pat: self.lower_pat(&f.node.pat),
                             is_shorthand: f.node.is_shorthand,
                         },
@@ -3091,10 +3091,7 @@ impl<'a> LoweringContext<'a> {
                 P(self.lower_expr(el)),
                 P(self.lower_expr(er)),
             ),
-            ExprKind::Field(ref el, ident) => hir::ExprField(
-                P(self.lower_expr(el)),
-                respan(ident.span, self.lower_ident(ident)),
-            ),
+            ExprKind::Field(ref el, ident) => hir::ExprField(P(self.lower_expr(el)), ident),
             ExprKind::Index(ref el, ref er) => {
                 hir::ExprIndex(P(self.lower_expr(el)), P(self.lower_expr(er)))
             }
@@ -3134,7 +3131,8 @@ impl<'a> LoweringContext<'a> {
                         let expr = P(self.lower_expr(&e));
                         let unstable_span =
                             self.allow_internal_unstable(CompilerDesugaringKind::DotFill, e.span);
-                        self.field(Symbol::intern(s), expr, unstable_span)
+                        let ident = Ident::new(Symbol::intern(s), unstable_span);
+                        self.field(ident, expr, unstable_span)
                     })
                     .collect::<P<[hir::Field]>>();
 
@@ -3749,10 +3747,10 @@ impl<'a> LoweringContext<'a> {
         }
     }
 
-    fn field(&mut self, name: Name, expr: P<hir::Expr>, span: Span) -> hir::Field {
+    fn field(&mut self, ident: Ident, expr: P<hir::Expr>, span: Span) -> hir::Field {
         hir::Field {
             id: self.next_id().node_id,
-            name: Spanned { node: name, span },
+            ident,
             span,
             expr,
             is_shorthand: false,

src/librustc/hir/map/mod.rs

@@ -909,7 +909,7 @@ impl<'hir> Map<'hir> {
             NodeImplItem(ii) => ii.name,
             NodeTraitItem(ti) => ti.name,
             NodeVariant(v) => v.node.name,
-            NodeField(f) => f.name,
+            NodeField(f) => f.ident.name,
             NodeLifetime(lt) => lt.name.name(),
             NodeTyParam(tp) => tp.name,
             NodeBinding(&Pat { node: PatKind::Binding(_,_,l,_), .. }) => l.node,
@@ -1105,7 +1105,7 @@ impl<T:Named> Named for Spanned<T> { fn name(&self) -> Name { self.node.name() }
 impl Named for Item { fn name(&self) -> Name { self.name } }
 impl Named for ForeignItem { fn name(&self) -> Name { self.name } }
 impl Named for Variant_ { fn name(&self) -> Name { self.name } }
-impl Named for StructField { fn name(&self) -> Name { self.name } }
+impl Named for StructField { fn name(&self) -> Name { self.ident.name } }
 impl Named for TraitItem { fn name(&self) -> Name { self.name } }
 impl Named for ImplItem { fn name(&self) -> Name { self.name } }
 
@@ -1291,7 +1291,7 @@ fn node_id_to_string(map: &Map, id: NodeId, include_id: bool) -> String {
         }
         Some(NodeField(ref field)) => {
             format!("field {} in {}{}",
-                    field.name,
+                    field.ident,
                     path_str(), id_str)
         }
         Some(NodeAnonConst(_)) => {

src/librustc/hir/mod.rs

@@ -35,7 +35,7 @@ use mir::mono::Linkage;
 use syntax_pos::{Span, DUMMY_SP};
 use syntax::codemap::{self, Spanned};
 use rustc_target::spec::abi::Abi;
-use syntax::ast::{self, Name, NodeId, DUMMY_NODE_ID, AsmDialect};
+use syntax::ast::{self, Ident, Name, NodeId, DUMMY_NODE_ID, AsmDialect};
 use syntax::ast::{Attribute, Lit, StrStyle, FloatTy, IntTy, UintTy, MetaItem};
 use syntax::attr::InlineAttr;
 use syntax::ext::hygiene::SyntaxContext;
@@ -866,7 +866,7 @@ impl Pat {
 pub struct FieldPat {
     pub id: NodeId,
     /// The identifier for the field
-    pub name: Name,
+    pub ident: Ident,
     /// The pattern the field is destructured to
     pub pat: P<Pat>,
     pub is_shorthand: bool,
@@ -1211,7 +1211,7 @@ pub struct Arm {
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub struct Field {
     pub id: NodeId,
-    pub name: Spanned<Name>,
+    pub ident: Ident,
     pub expr: P<Expr>,
     pub span: Span,
     pub is_shorthand: bool,
@@ -1414,7 +1414,7 @@ pub enum Expr_ {
     /// For example, `a += 1`.
     ExprAssignOp(BinOp, P<Expr>, P<Expr>),
     /// Access of a named (`obj.foo`) or unnamed (`obj.0`) struct or tuple field
-    ExprField(P<Expr>, Spanned<Name>),
+    ExprField(P<Expr>, Ident),
     /// An indexing operation (`foo[2]`)
     ExprIndex(P<Expr>, P<Expr>),
 
@@ -1973,7 +1973,7 @@ impl Visibility {
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub struct StructField {
     pub span: Span,
-    pub name: Name,
+    pub ident: Ident,
     pub vis: Visibility,
     pub id: NodeId,
     pub ty: P<Ty>,
@@ -1983,7 +1983,7 @@ pub struct StructField {
 impl StructField {
     // Still necessary in couple of places
     pub fn is_positional(&self) -> bool {
-        let first = self.name.as_str().as_bytes()[0];
+        let first = self.ident.as_str().as_bytes()[0];
         first >= b'0' && first <= b'9'
     }
 }

src/librustc/hir/print.rs

@@ -857,7 +857,7 @@ impl<'a> State<'a> {
                 self.maybe_print_comment(field.span.lo())?;
                 self.print_outer_attributes(&field.attrs)?;
                 self.print_visibility(&field.vis)?;
-                self.print_name(field.name)?;
+                self.print_ident(field.ident)?;
                 self.word_nbsp(":")?;
                 self.print_type(&field.ty)?;
                 self.s.word(",")?;
@@ -1166,7 +1166,7 @@ impl<'a> State<'a> {
                            |s, field| {
                                s.ibox(indent_unit)?;
                                if !field.is_shorthand {
-                                    s.print_name(field.name.node)?;
+                                    s.print_ident(field.ident)?;
                                     s.word_space(":")?;
                                }
                                s.print_expr(&field.expr)?;
@@ -1406,10 +1406,10 @@ impl<'a> State<'a> {
                 self.word_space("=")?;
                 self.print_expr_maybe_paren(&rhs, prec)?;
             }
-            hir::ExprField(ref expr, name) => {
+            hir::ExprField(ref expr, ident) => {
                 self.print_expr_maybe_paren(expr, parser::PREC_POSTFIX)?;
                 self.s.word(".")?;
-                self.print_name(name.node)?;
+                self.print_ident(ident)?;
             }
             hir::ExprIndex(ref expr, ref index) => {
                 self.print_expr_maybe_paren(&expr, parser::PREC_POSTFIX)?;
@@ -1561,13 +1561,17 @@ impl<'a> State<'a> {
         self.s.word(&i.to_string())
     }
 
-    pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
-        if name.to_ident().is_raw_guess() {
-            self.s.word(&format!("r#{}", name))?;
+    pub fn print_ident(&mut self, ident: ast::Ident) -> io::Result<()> {
+        if ident.is_raw_guess() {
+            self.s.word(&format!("r#{}", ident.name))?;
         } else {
-            self.s.word(&name.as_str())?;
+            self.s.word(&ident.as_str())?;
         }
-        self.ann.post(self, NodeName(&name))
+        self.ann.post(self, NodeName(&ident.name))
+    }
+
+    pub fn print_name(&mut self, name: ast::Name) -> io::Result<()> {
+        self.print_ident(name.to_ident())
     }
 
     pub fn print_for_decl(&mut self, loc: &hir::Local, coll: &hir::Expr) -> io::Result<()> {
@@ -1773,7 +1777,7 @@ impl<'a> State<'a> {
                                    |s, f| {
                                        s.cbox(indent_unit)?;
                                        if !f.node.is_shorthand {
-                                           s.print_name(f.node.name)?;
+                                           s.print_ident(f.node.ident)?;
                                            s.word_nbsp(":")?;
                                        }
                                        s.print_pat(&f.node.pat)?;

src/librustc/ich/impls_hir.rs

@@ -427,12 +427,12 @@ impl<'a> HashStable<StableHashingContext<'a>> for hir::FieldPat {
                                           hasher: &mut StableHasher<W>) {
         let hir::FieldPat {
             id: _,
-            name,
+            ident,
             ref pat,
             is_shorthand,
         } = *self;
 
-        name.hash_stable(hcx, hasher);
+        ident.hash_stable(hcx, hasher);
         pat.hash_stable(hcx, hasher);
         is_shorthand.hash_stable(hcx, hasher);
     }
@@ -525,13 +525,13 @@ impl<'a> HashStable<StableHashingContext<'a>> for hir::Field {
                                           hasher: &mut StableHasher<W>) {
         let hir::Field {
             id: _,
-            name,
+            ident,
             ref expr,
             span,
             is_shorthand,
         } = *self;
 
-        name.hash_stable(hcx, hasher);
+        ident.hash_stable(hcx, hasher);
         expr.hash_stable(hcx, hasher);
         span.hash_stable(hcx, hasher);
         is_shorthand.hash_stable(hcx, hasher);
@@ -598,7 +598,7 @@ impl_stable_hash_for!(enum hir::Expr_ {
     ExprBlock(blk, label),
     ExprAssign(lhs, rhs),
     ExprAssignOp(op, lhs, rhs),
-    ExprField(owner, field_name),
+    ExprField(owner, ident),
     ExprIndex(lhs, rhs),
     ExprPath(path),
     ExprAddrOf(mutability, sub),
@@ -835,7 +835,7 @@ impl_stable_hash_for!(enum hir::UseKind {
 
 impl_stable_hash_for!(struct hir::StructField {
     span,
-    name,
+    ident,
     vis,
     id,
     ty,

src/librustc/ich/impls_ty.rs

@@ -357,11 +357,17 @@ impl_stable_hash_for!(enum ty::VariantDiscr {
     Relative(distance)
 });
 
-impl_stable_hash_for!(struct ty::FieldDef {
-    did,
-    name,
-    vis
-});
+impl<'a, 'gcx> HashStable<StableHashingContext<'a>> for ty::FieldDef {
+    fn hash_stable<W: StableHasherResult>(&self,
+                                          hcx: &mut StableHashingContext<'a>,
+                                          hasher: &mut StableHasher<W>) {
+        let ty::FieldDef { did, ident, vis } = *self;
+
+        did.hash_stable(hcx, hasher);
+        ident.name.hash_stable(hcx, hasher);
+        vis.hash_stable(hcx, hasher);
+    }
+}
 
 impl<'a, 'gcx> HashStable<StableHashingContext<'a>>
 for ::middle::const_val::ConstVal<'gcx> {

src/librustc/middle/dead.rs

@@ -588,7 +588,7 @@ impl<'a, 'tcx> Visitor<'tcx> for DeadVisitor<'a, 'tcx> {
 
     fn visit_struct_field(&mut self, field: &'tcx hir::StructField) {
         if self.should_warn_about_field(&field) {
-            self.warn_dead_code(field.id, field.span, field.name, "field", "used");
+            self.warn_dead_code(field.id, field.span, field.ident.name, "field", "used");
         }
         intravisit::walk_struct_field(self, field);
     }