Lifting Generics from MethodSig to TraitItem and ImplItem since we want to support generics in each variant of TraitItem and ImplItem

Author: sunjay

src/librustc/hir/lowering.rs

@@ -1548,15 +1548,15 @@ impl<'a> LoweringContext<'a> {
                     }
                     TraitItemKind::Method(ref sig, None) => {
                         let names = this.lower_fn_args_to_names(&sig.decl);
-                        hir::TraitItemKind::Method(this.lower_method_sig(sig),
+                        hir::TraitItemKind::Method(this.lower_method_sig(&i.generics, sig),
                                                    hir::TraitMethod::Required(names))
                     }
                     TraitItemKind::Method(ref sig, Some(ref body)) => {
                         let body_id = this.lower_body(Some(&sig.decl), |this| {
                             let body = this.lower_block(body, false);
                             this.expr_block(body, ThinVec::new())
                         });
-                        hir::TraitItemKind::Method(this.lower_method_sig(sig),
+                        hir::TraitItemKind::Method(this.lower_method_sig(&i.generics, sig),
                                                    hir::TraitMethod::Provided(body_id))
                     }
                     TraitItemKind::Type(ref bounds, ref default) => {
@@ -1615,7 +1615,7 @@ impl<'a> LoweringContext<'a> {
                             let body = this.lower_block(body, false);
                             this.expr_block(body, ThinVec::new())
                         });
-                        hir::ImplItemKind::Method(this.lower_method_sig(sig), body_id)
+                        hir::ImplItemKind::Method(this.lower_method_sig(&i.generics, sig), body_id)
                     }
                     ImplItemKind::Type(ref ty) => hir::ImplItemKind::Type(this.lower_ty(ty)),
                     ImplItemKind::Macro(..) => panic!("Shouldn't exist any more"),
@@ -1727,9 +1727,9 @@ impl<'a> LoweringContext<'a> {
         })
     }
 
-    fn lower_method_sig(&mut self, sig: &MethodSig) -> hir::MethodSig {
+    fn lower_method_sig(&mut self, generics: &Generics, sig: &MethodSig) -> hir::MethodSig {
         hir::MethodSig {
-            generics: self.lower_generics(&sig.generics),
+            generics: self.lower_generics(generics),
             abi: sig.abi,
             unsafety: self.lower_unsafety(sig.unsafety),
             constness: self.lower_constness(sig.constness),

src/librustc_resolve/lib.rs

@@ -723,7 +723,6 @@ impl<'a, 'tcx> Visitor<'tcx> for Resolver<'a> {
                 ItemRibKind
             }
             FnKind::Method(_, sig, _, _) => {
-                self.visit_generics(&sig.generics);
                 MethodRibKind(!sig.decl.has_self())
             }
             FnKind::Closure(_) => ClosureRibKind(node_id),
@@ -1864,6 +1863,7 @@ impl<'a> Resolver<'a> {
 
                         for trait_item in trait_items {
                             this.check_proc_macro_attrs(&trait_item.attrs);
+                            this.visit_generics(&trait_item.generics);
 
                             match trait_item.node {
                                 TraitItemKind::Const(ref ty, ref default) => {
@@ -1880,7 +1880,7 @@ impl<'a> Resolver<'a> {
                                 }
                                 TraitItemKind::Method(ref sig, _) => {
                                     let type_parameters =
-                                        HasTypeParameters(&sig.generics,
+                                        HasTypeParameters(&trait_item.generics,
                                                           MethodRibKind(!sig.decl.has_self()));
                                     this.with_type_parameter_rib(type_parameters, |this| {
                                         visit::walk_trait_item(this, trait_item)
@@ -2075,6 +2075,7 @@ impl<'a> Resolver<'a> {
                         this.with_current_self_type(self_type, |this| {
                             for impl_item in impl_items {
                                 this.check_proc_macro_attrs(&impl_item.attrs);
+                                this.visit_generics(&impl_item.generics);
                                 this.resolve_visibility(&impl_item.vis);
                                 match impl_item.node {
                                     ImplItemKind::Const(..) => {
@@ -2097,7 +2098,7 @@ impl<'a> Resolver<'a> {
                                         // We also need a new scope for the method-
                                         // specific type parameters.
                                         let type_parameters =
-                                            HasTypeParameters(&sig.generics,
+                                            HasTypeParameters(&impl_item.generics,
                                                             MethodRibKind(!sig.decl.has_self()));
                                         this.with_type_parameter_rib(type_parameters, |this| {
                                             visit::walk_impl_item(this, impl_item);

src/librustc_save_analysis/dump_visitor.rs

@@ -354,23 +354,24 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                       body: Option<&'l ast::Block>,
                       id: ast::NodeId,
                       name: ast::Ident,
+                      generics: &'l ast::Generics,
                       vis: ast::Visibility,
                       span: Span) {
         debug!("process_method: {}:{}", id, name);
 
         if let Some(mut method_data) = self.save_ctxt.get_method_data(id, name.name, span) {
 
-            let sig_str = ::make_signature(&sig.decl, &sig.generics);
+            let sig_str = ::make_signature(&sig.decl, &generics);
             if body.is_some() {
                 self.nest_tables(id, |v| {
                     v.process_formals(&sig.decl.inputs, &method_data.qualname)
                 });
             }
 
-            self.process_generic_params(&sig.generics, span, &method_data.qualname, id);
+            self.process_generic_params(&generics, span, &method_data.qualname, id);
 
             method_data.value = sig_str;
-            method_data.sig = sig::method_signature(id, name, sig, &self.save_ctxt);
+            method_data.sig = sig::method_signature(id, name, generics, sig, &self.save_ctxt);
             self.dumper.dump_def(vis == ast::Visibility::Public, method_data);
         }
 
@@ -1007,6 +1008,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                                     body.as_ref().map(|x| &**x),
                                     trait_item.id,
                                     trait_item.ident,
+                                    &trait_item.generics,
                                     ast::Visibility::Public,
                                     trait_item.span);
             }
@@ -1066,6 +1068,7 @@ impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
                                     Some(body),
                                     impl_item.id,
                                     impl_item.ident,
+                                    &impl_item.generics,
                                     impl_item.vis.clone(),
                                     impl_item.span);
             }

src/librustc_save_analysis/sig.rs

@@ -77,13 +77,14 @@ pub fn variant_signature(variant: &ast::Variant, scx: &SaveContext) -> Option<Si
 
 pub fn method_signature(id: NodeId,
                         ident: ast::Ident,
+                        generics: &ast::Generics,
                         m: &ast::MethodSig,
                         scx: &SaveContext)
                         -> Option<Signature> {
     if !scx.config.signatures {
         return None;
     }
-    make_method_signature(id, ident, m, scx).ok()
+    make_method_signature(id, ident, generics, m, scx).ok()
 }
 
 pub fn assoc_const_signature(id: NodeId,
@@ -895,6 +896,7 @@ fn make_assoc_const_signature(id: NodeId,
 
 fn make_method_signature(id: NodeId,
                          ident: ast::Ident,
+                         generics: &ast::Generics,
                          m: &ast::MethodSig,
                          scx: &SaveContext)
                          -> Result {
@@ -915,7 +917,7 @@ fn make_method_signature(id: NodeId,
 
     let mut sig = name_and_generics(text,
                                     0,
-                                    &m.generics,
+                                    generics,
                                     id,
                                     ident,
                                     scx)?;

src/libsyntax/ast.rs

@@ -1178,7 +1178,6 @@ pub struct MethodSig {
     pub constness: Spanned<Constness>,
     pub abi: Abi,
     pub decl: P<FnDecl>,
-    pub generics: Generics,
 }
 
 /// Represents an item declaration within a trait declaration,
@@ -1190,6 +1189,7 @@ pub struct TraitItem {
     pub id: NodeId,
     pub ident: Ident,
     pub attrs: Vec<Attribute>,
+    pub generics: Generics,
     pub node: TraitItemKind,
     pub span: Span,
     /// See `Item::tokens` for what this is
@@ -1211,6 +1211,7 @@ pub struct ImplItem {
     pub vis: Visibility,
     pub defaultness: Defaultness,
     pub attrs: Vec<Attribute>,
+    pub generics: Generics,
     pub node: ImplItemKind,
     pub span: Span,
     /// See `Item::tokens` for what this is

src/libsyntax/ext/placeholders.rs

@@ -32,6 +32,7 @@ pub fn placeholder(kind: ExpansionKind, id: ast::NodeId) -> Expansion {
 
     let ident = keywords::Invalid.ident();
     let attrs = Vec::new();
+    let generics = ast::Generics::default();
     let vis = ast::Visibility::Inherited;
     let span = DUMMY_SP;
     let expr_placeholder = || P(ast::Expr {
@@ -49,12 +50,12 @@ pub fn placeholder(kind: ExpansionKind, id: ast::NodeId) -> Expansion {
             tokens: None,
         }))),
         ExpansionKind::TraitItems => Expansion::TraitItems(SmallVector::one(ast::TraitItem {
-            id, span, ident, attrs,
+            id, span, ident, attrs, generics,
             node: ast::TraitItemKind::Macro(mac_placeholder()),
             tokens: None,
         })),
         ExpansionKind::ImplItems => Expansion::ImplItems(SmallVector::one(ast::ImplItem {
-            id, span, ident, vis, attrs,
+            id, span, ident, vis, attrs, generics,
             node: ast::ImplItemKind::Macro(mac_placeholder()),
             defaultness: ast::Defaultness::Final,
             tokens: None,

src/libsyntax/fold.rs

@@ -943,6 +943,7 @@ pub fn noop_fold_trait_item<T: Folder>(i: TraitItem, folder: &mut T)
         id: folder.new_id(i.id),
         ident: folder.fold_ident(i.ident),
         attrs: fold_attrs(i.attrs, folder),
+        generics: folder.fold_generics(i.generics),
         node: match i.node {
             TraitItemKind::Const(ty, default) => {
                 TraitItemKind::Const(folder.fold_ty(ty),
@@ -972,6 +973,7 @@ pub fn noop_fold_impl_item<T: Folder>(i: ImplItem, folder: &mut T)
         vis: folder.fold_vis(i.vis),
         ident: folder.fold_ident(i.ident),
         attrs: fold_attrs(i.attrs, folder),
+        generics: folder.fold_generics(i.generics),
         defaultness: i.defaultness,
         node: match i.node  {
             ast::ImplItemKind::Const(ty, expr) => {
@@ -1074,7 +1076,6 @@ pub fn noop_fold_foreign_item<T: Folder>(ni: ForeignItem, folder: &mut T) -> For
 
 pub fn noop_fold_method_sig<T: Folder>(sig: MethodSig, folder: &mut T) -> MethodSig {
     MethodSig {
-        generics: folder.fold_generics(sig.generics),
         abi: sig.abi,
         unsafety: sig.unsafety,
         constness: sig.constness,

src/libsyntax/parse/parser.rs

@@ -1287,10 +1287,10 @@ impl<'a> Parser<'a> {
                          mut attrs: Vec<Attribute>) -> PResult<'a, TraitItem> {
         let lo = self.span;
 
-        let (name, node) = if self.eat_keyword(keywords::Type) {
+        let (name, node, generics) = if self.eat_keyword(keywords::Type) {
             let TyParam {ident, bounds, default, ..} = self.parse_ty_param(vec![])?;
             self.expect(&token::Semi)?;
-            (ident, TraitItemKind::Type(bounds, default))
+            (ident, TraitItemKind::Type(bounds, default), ast::Generics::default())
         } else if self.is_const_item() {
             self.expect_keyword(keywords::Const)?;
             let ident = self.parse_ident()?;
@@ -1305,7 +1305,7 @@ impl<'a> Parser<'a> {
                 self.expect(&token::Semi)?;
                 None
             };
-            (ident, TraitItemKind::Const(ty, default))
+            (ident, TraitItemKind::Const(ty, default), ast::Generics::default())
         } else if self.token.is_path_start() {
             // trait item macro.
             // code copied from parse_macro_use_or_failure... abstraction!
@@ -1328,7 +1328,7 @@ impl<'a> Parser<'a> {
             }
 
             let mac = respan(lo.to(self.prev_span), Mac_ { path: pth, tts: tts });
-            (keywords::Invalid.ident(), ast::TraitItemKind::Macro(mac))
+            (keywords::Invalid.ident(), ast::TraitItemKind::Macro(mac), ast::Generics::default())
         } else {
             let (constness, unsafety, abi) = self.parse_fn_front_matter()?;
 
@@ -1341,13 +1341,12 @@ impl<'a> Parser<'a> {
                 // definition...
                 p.parse_arg_general(false)
             })?;
-
             generics.where_clause = self.parse_where_clause()?;
+
             let sig = ast::MethodSig {
                 unsafety,
                 constness,
                 decl: d,
-                generics,
                 abi,
             };
 
@@ -1370,13 +1369,14 @@ impl<'a> Parser<'a> {
                     return Err(self.fatal(&format!("expected `;` or `{{`, found `{}`", token_str)));
                 }
             };
-            (ident, ast::TraitItemKind::Method(sig, body))
+            (ident, ast::TraitItemKind::Method(sig, body), generics)
         };
 
         Ok(TraitItem {
             id: ast::DUMMY_NODE_ID,
             ident: name,
             attrs,
+            generics,
             node,
             span: lo.to(self.prev_span),
             tokens: None,
@@ -4901,12 +4901,12 @@ impl<'a> Parser<'a> {
         let lo = self.span;
         let vis = self.parse_visibility(false)?;
         let defaultness = self.parse_defaultness()?;
-        let (name, node) = if self.eat_keyword(keywords::Type) {
+        let (name, node, generics) = if self.eat_keyword(keywords::Type) {
             let name = self.parse_ident()?;
             self.expect(&token::Eq)?;
             let typ = self.parse_ty()?;
             self.expect(&token::Semi)?;
-            (name, ast::ImplItemKind::Type(typ))
+            (name, ast::ImplItemKind::Type(typ), ast::Generics::default())
         } else if self.is_const_item() {
             self.expect_keyword(keywords::Const)?;
             let name = self.parse_ident()?;
@@ -4915,11 +4915,11 @@ impl<'a> Parser<'a> {
             self.expect(&token::Eq)?;
             let expr = self.parse_expr()?;
             self.expect(&token::Semi)?;
-            (name, ast::ImplItemKind::Const(typ, expr))
+            (name, ast::ImplItemKind::Const(typ, expr), ast::Generics::default())
         } else {
-            let (name, inner_attrs, node) = self.parse_impl_method(&vis, at_end)?;
+            let (name, inner_attrs, generics, node) = self.parse_impl_method(&vis, at_end)?;
             attrs.extend(inner_attrs);
-            (name, node)
+            (name, node, generics)
         };
 
         Ok(ImplItem {
@@ -4929,6 +4929,7 @@ impl<'a> Parser<'a> {
             vis,
             defaultness,
             attrs,
+            generics,
             node,
             tokens: None,
         })
@@ -4986,7 +4987,7 @@ impl<'a> Parser<'a> {
 
     /// Parse a method or a macro invocation in a trait impl.
     fn parse_impl_method(&mut self, vis: &Visibility, at_end: &mut bool)
-                         -> PResult<'a, (Ident, Vec<ast::Attribute>, ast::ImplItemKind)> {
+                         -> PResult<'a, (Ident, Vec<ast::Attribute>, ast::Generics, ast::ImplItemKind)> {
         // code copied from parse_macro_use_or_failure... abstraction!
         if self.token.is_path_start() {
             // Method macro.
@@ -5013,7 +5014,7 @@ impl<'a> Parser<'a> {
             }
 
             let mac = respan(lo.to(self.prev_span), Mac_ { path: pth, tts: tts });
-            Ok((keywords::Invalid.ident(), vec![], ast::ImplItemKind::Macro(mac)))
+            Ok((keywords::Invalid.ident(), vec![], ast::Generics::default(), ast::ImplItemKind::Macro(mac)))
         } else {
             let (constness, unsafety, abi) = self.parse_fn_front_matter()?;
             let ident = self.parse_ident()?;
@@ -5022,8 +5023,7 @@ impl<'a> Parser<'a> {
             generics.where_clause = self.parse_where_clause()?;
             *at_end = true;
             let (inner_attrs, body) = self.parse_inner_attrs_and_block()?;
-            Ok((ident, inner_attrs, ast::ImplItemKind::Method(ast::MethodSig {
-                generics,
+            Ok((ident, inner_attrs, generics, ast::ImplItemKind::Method(ast::MethodSig {
                 abi,
                 unsafety,
                 constness,

src/libsyntax/print/pprust.rs

@@ -1525,6 +1525,7 @@ impl<'a> State<'a> {
 
     pub fn print_method_sig(&mut self,
                             ident: ast::Ident,
+                            generics: &ast::Generics,
                             m: &ast::MethodSig,
                             vis: &ast::Visibility)
                             -> io::Result<()> {
@@ -1533,7 +1534,7 @@ impl<'a> State<'a> {
                       m.constness.node,
                       m.abi,
                       Some(ident),
-                      &m.generics,
+                      &generics,
                       vis)
     }
 
@@ -1553,7 +1554,7 @@ impl<'a> State<'a> {
                 if body.is_some() {
                     self.head("")?;
                 }
-                self.print_method_sig(ti.ident, sig, &ast::Visibility::Inherited)?;
+                self.print_method_sig(ti.ident, &ti.generics, sig, &ast::Visibility::Inherited)?;
                 if let Some(ref body) = *body {
                     self.nbsp()?;
                     self.print_block_with_attrs(body, &ti.attrs)?;
@@ -1592,7 +1593,7 @@ impl<'a> State<'a> {
             }
             ast::ImplItemKind::Method(ref sig, ref body) => {
                 self.head("")?;
-                self.print_method_sig(ii.ident, sig, &ii.vis)?;
+                self.print_method_sig(ii.ident, &ii.generics, sig, &ii.vis)?;
                 self.nbsp()?;
                 self.print_block_with_attrs(body, &ii.attrs)?;
             }