Get rid of ast::StructFieldKind

src/librustc_front/lowering.rs

@@ -622,9 +622,8 @@ pub fn lower_struct_field(lctx: &LoweringContext,
     hir::StructField {
         span: f.span,
         id: f.node.id,
-        name: f.node.ident().map(|ident| ident.name)
+        name: f.node.ident.map(|ident| ident.name).unwrap_or(token::intern(&index.to_string())),
-                            .unwrap_or(token::intern(&index.to_string())),
+        vis: lower_visibility(lctx, f.node.vis),
-        vis: lower_visibility(lctx, f.node.kind.visibility()),
         ty: lower_ty(lctx, &f.node.ty),
         attrs: lower_attrs(lctx, &f.node.attrs),
     }

src/librustc_save_analysis/lib.rs

@@ -246,8 +246,7 @@ impl<'l, 'tcx: 'l> SaveContext<'l, 'tcx> {
 
     pub fn get_field_data(&self, field: &ast::StructField,
                           scope: NodeId) -> Option<VariableData> {
-        match field.node.kind {
+        if let Some(ident) = field.node.ident {
-            ast::NamedField(ident, _) => {
             let qualname = format!("::{}::{}", self.tcx.map.path_to_string(scope), ident);
             let typ = self.tcx.node_types().get(&field.node.id).unwrap().to_string();
             let sub_span = self.span_utils.sub_span_before_token(field.span, token::Colon);
@@ -261,8 +260,8 @@ impl<'l, 'tcx: 'l> SaveContext<'l, 'tcx> {
                 value: "".to_owned(),
                 type_value: typ,
             })
-            }
+        } else {
-            _ => None,
+            None
         }
     }
 

src/libsyntax/ast.rs

@@ -10,7 +10,6 @@
 
 // The Rust abstract syntax tree.
 
-pub use self::StructFieldKind::*;
 pub use self::TyParamBound::*;
 pub use self::UnsafeSource::*;
 pub use self::ViewPath_::*;
@@ -1878,45 +1877,15 @@ pub enum Visibility {
 
 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub struct StructField_ {
-    pub kind: StructFieldKind,
+    pub ident: Option<Ident>,
+    pub vis: Visibility,
     pub id: NodeId,
     pub ty: P<Ty>,
     pub attrs: Vec<Attribute>,
 }
 
-impl StructField_ {
-    pub fn ident(&self) -> Option<Ident> {
-        match self.kind {
-            NamedField(ref ident, _) => Some(ident.clone()),
-            UnnamedField(_) => None
-        }
-    }
-}
-
 pub type StructField = Spanned<StructField_>;
 
-#[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
-pub enum StructFieldKind {
-    NamedField(Ident, Visibility),
-    /// Element of a tuple-like struct
-    UnnamedField(Visibility),
-}
-
-impl StructFieldKind {
-    pub fn is_unnamed(&self) -> bool {
-        match *self {
-            UnnamedField(..) => true,
-            NamedField(..) => false,
-        }
-    }
-
-    pub fn visibility(&self) -> &Visibility {
-        match *self {
-            NamedField(_, ref vis) | UnnamedField(ref vis) => vis
-        }
-    }
-}
-
 /// Fields and Ids of enum variants and structs
 ///
 /// For enum variants: `NodeId` represents both an Id of the variant itself (relevant for all

src/libsyntax/ast_util.rs

@@ -95,12 +95,6 @@ pub fn impl_pretty_name(trait_ref: &Option<TraitRef>, ty: Option<&Ty>) -> Ident
     token::gensym_ident(&pretty[..])
 }
 
-pub fn struct_field_visibility(field: ast::StructField) -> Visibility {
-    match field.node.kind {
-        ast::NamedField(_, v) | ast::UnnamedField(v) => v
-    }
-}
-
 // ______________________________________________________________________
 // Enumerating the IDs which appear in an AST
 

src/libsyntax/ext/build.rs

@@ -1009,7 +1009,8 @@ impl<'a> AstBuilder for ExtCtxt<'a> {
         let fields: Vec<_> = tys.into_iter().map(|ty| {
             Spanned { span: ty.span, node: ast::StructField_ {
                 ty: ty,
-                kind: ast::UnnamedField(ast::Visibility::Inherited),
+                ident: None,
+                vis: ast::Visibility::Inherited,
                 attrs: Vec::new(),
                 id: ast::DUMMY_NODE_ID,
             }}

src/libsyntax/fold.rs

@@ -847,15 +847,15 @@ pub fn noop_fold_poly_trait_ref<T: Folder>(p: PolyTraitRef, fld: &mut T) -> Poly
 }
 
 pub fn noop_fold_struct_field<T: Folder>(f: StructField, fld: &mut T) -> StructField {
-    let StructField {node: StructField_ {id, kind, ty, attrs}, span} = f;
     Spanned {
         node: StructField_ {
-            id: fld.new_id(id),
+            id: fld.new_id(f.node.id),
-            kind: kind,
+            ident: f.node.ident.map(|ident| fld.fold_ident(ident)),
-            ty: fld.fold_ty(ty),
+            vis: f.node.vis,
-            attrs: fold_attrs(attrs, fld),
+            ty: fld.fold_ty(f.node.ty),
+            attrs: fold_attrs(f.node.attrs, fld),
         },
-        span: fld.new_span(span)
+        span: fld.new_span(f.span)
     }
 }
 

src/libsyntax/parse/parser.rs

@@ -29,7 +29,6 @@ use ast::Local;
 use ast::MacStmtStyle;
 use ast::Mac_;
 use ast::{MutTy, Mutability};
-use ast::NamedField;
 use ast::{Pat, PatKind};
 use ast::{PolyTraitRef, QSelf};
 use ast::{Stmt, StmtKind};
@@ -38,7 +37,6 @@ use ast::StrStyle;
 use ast::SelfKind;
 use ast::{Delimited, SequenceRepetition, TokenTree, TraitItem, TraitRef};
 use ast::{Ty, TyKind, TypeBinding, TyParam, TyParamBounds};
-use ast::UnnamedField;
 use ast::{ViewPath, ViewPathGlob, ViewPathList, ViewPathSimple};
 use ast::{Visibility, WhereClause};
 use attr::{ThinAttributes, ThinAttributesExt, AttributesExt};
@@ -3848,7 +3846,8 @@ impl<'a> Parser<'a> {
         self.expect(&token::Colon)?;
         let ty = self.parse_ty_sum()?;
         Ok(spanned(lo, self.last_span.hi, ast::StructField_ {
-            kind: NamedField(name, pr),
+            ident: Some(name),
+            vis: pr,
             id: ast::DUMMY_NODE_ID,
             ty: ty,
             attrs: attrs,
@@ -5247,7 +5246,8 @@ impl<'a> Parser<'a> {
                 let attrs = p.parse_outer_attributes()?;
                 let lo = p.span.lo;
                 let struct_field_ = ast::StructField_ {
-                    kind: UnnamedField(p.parse_visibility()?),
+                    vis: p.parse_visibility()?,
+                    ident: None,
                     id: ast::DUMMY_NODE_ID,
                     ty: p.parse_ty_sum()?,
                     attrs: attrs,

src/libsyntax/print/pprust.rs

@@ -1407,15 +1407,10 @@ impl<'a> State<'a> {
                 self.commasep(
                     Inconsistent, struct_def.fields(),
                     |s, field| {
-                        match field.node.kind {
+                        s.print_visibility(field.node.vis)?;
-                            ast::NamedField(..) => panic!("unexpected named field"),
-                            ast::UnnamedField(ref vis) => {
-                                s.print_visibility(vis)?;
                         s.maybe_print_comment(field.span.lo)?;
                         s.print_type(&field.node.ty)
                     }
-                        }
-                    }
                 )?;
                 self.pclose()?;
             }
@@ -1432,20 +1427,15 @@ impl<'a> State<'a> {
             self.hardbreak_if_not_bol()?;
 
             for field in struct_def.fields() {
-                match field.node.kind {
-                    ast::UnnamedField(..) => panic!("unexpected unnamed field"),
-                    ast::NamedField(ident, ref visibility) => {
                 self.hardbreak_if_not_bol()?;
                 self.maybe_print_comment(field.span.lo)?;
                 self.print_outer_attributes(&field.node.attrs)?;
-                        self.print_visibility(visibility)?;
+                self.print_visibility(field.node.vis)?;
-                        self.print_ident(ident)?;
+                self.print_ident(field.node.ident.unwrap())?;
                 self.word_nbsp(":")?;
                 self.print_type(&field.node.ty)?;
                 word(&mut self.s, ",")?;
             }
-                }
-            }
 
             self.bclose(span)
         }

src/libsyntax/visit.rs

@@ -619,7 +619,7 @@ pub fn walk_struct_def<'v, V: Visitor<'v>>(visitor: &mut V,
 
 pub fn walk_struct_field<'v, V: Visitor<'v>>(visitor: &mut V,
                                              struct_field: &'v StructField) {
-    walk_opt_ident(visitor, struct_field.span, struct_field.node.ident());
+    walk_opt_ident(visitor, struct_field.span, struct_field.node.ident);
     visitor.visit_ty(&struct_field.node.ty);
     walk_list!(visitor, visit_attribute, &struct_field.node.attrs);
 }

src/libsyntax_ext/deriving/generic/mod.rs

@@ -186,7 +186,6 @@
 
 pub use self::StaticFields::*;
 pub use self::SubstructureFields::*;
-use self::StructType::*;
 
 use std::cell::RefCell;
 use std::collections::HashSet;
@@ -1409,11 +1408,6 @@ impl<'a> MethodDef<'a> {
     }
 }
 
-#[derive(PartialEq)] // dogfooding!
-enum StructType {
-    Unknown, Record, Tuple
-}
-
 // general helper methods.
 impl<'a> TraitDef<'a> {
     fn set_expn_info(&self,
@@ -1441,9 +1435,9 @@ impl<'a> TraitDef<'a> {
         let mut just_spans = Vec::new();
         for field in struct_def.fields(){
             let sp = self.set_expn_info(cx, field.span);
-            match field.node.kind {
+            match field.node.ident {
-                ast::NamedField(ident, _) => named_idents.push((ident, sp)),
+                Some(ident) => named_idents.push((ident, sp)),
-                ast::UnnamedField(..) => just_spans.push(sp),
+                _ => just_spans.push(sp),
             }
         }
 
@@ -1479,53 +1473,26 @@ impl<'a> TraitDef<'a> {
                              -> (P<ast::Pat>, Vec<(Span, Option<Ident>,
                                                    P<Expr>,
                                                    &'a [ast::Attribute])>) {
-        if struct_def.fields().is_empty() {
-            if struct_def.is_struct() {
-                return (cx.pat_struct(self.span, struct_path, vec![]), vec![]);
-            } else {
-                return (cx.pat_enum(self.span, struct_path, vec![]), vec![]);
-            }
-        }
-
         let mut paths = Vec::new();
-        let mut ident_expr = Vec::new();
+        let mut ident_exprs = Vec::new();
-        let mut struct_type = Unknown;
-
         for (i, struct_field) in struct_def.fields().iter().enumerate() {
             let sp = self.set_expn_info(cx, struct_field.span);
-            let opt_id = match struct_field.node.kind {
-                ast::NamedField(ident, _) if (struct_type == Unknown ||
-                                              struct_type == Record) => {
-                    struct_type = Record;
-                    Some(ident)
-                }
-                ast::UnnamedField(..) if (struct_type == Unknown ||
-                                          struct_type == Tuple) => {
-                    struct_type = Tuple;
-                    None
-                }
-                _ => {
-                    cx.span_bug(sp, "a struct with named and unnamed fields in `derive`");
-                }
-            };
             let ident = cx.ident_of(&format!("{}_{}", prefix, i));
             paths.push(codemap::Spanned{span: sp, node: ident});
             let val = cx.expr_deref(sp, cx.expr_path(cx.path_ident(sp,ident)));
             let val = cx.expr(sp, ast::ExprKind::Paren(val));
-            ident_expr.push((sp, opt_id, val, &struct_field.node.attrs[..]));
+            ident_exprs.push((sp, struct_field.node.ident, val, &struct_field.node.attrs[..]));
         }
 
         let subpats = self.create_subpatterns(cx, paths, mutbl);
-
-        // struct_type is definitely not Unknown, since struct_def.fields
-        // must be nonempty to reach here
         let pattern = if struct_def.is_struct() {
-            let field_pats = subpats.into_iter().zip(&ident_expr)
+            let field_pats = subpats.into_iter().zip(&ident_exprs).map(|(pat, &(sp, ident, _, _))| {
-                                    .map(|(pat, &(_, id, _, _))| {
+                if ident.is_none() {
-                // id is guaranteed to be Some
+                    cx.span_bug(sp, "a braced struct with unnamed fields in `derive`");
+                }
                 codemap::Spanned {
                     span: pat.span,
-                    node: ast::FieldPat { ident: id.unwrap(), pat: pat, is_shorthand: false },
+                    node: ast::FieldPat { ident: ident.unwrap(), pat: pat, is_shorthand: false },
                 }
             }).collect();
             cx.pat_struct(self.span, struct_path, field_pats)
@@ -1533,7 +1500,7 @@ impl<'a> TraitDef<'a> {
             cx.pat_enum(self.span, struct_path, subpats)
         };
 
-        (pattern, ident_expr)
+        (pattern, ident_exprs)
     }
 
     fn create_enum_variant_pattern(&self,