auto merge of #15646 : jbclements/rust/method-macros, r=cmr

This patch adds support for macros in method position. It follows roughly the template for Item macros, where an outer `Method` wrapper contains a `Method_` enum which can either be a macro invocation or a standard macro definition. 

One note; adding support for macros that expand into multiple methods is not included here, but should be a simple parser change, since this patch updates the type of fold_macro to return a smallvector of methods.

For reviewers, please pay special attention to the parser changes; these are the ones I'm most concerned about.

Because of the small change to the interface of fold_method, this is a ...

[breaking change]

Author: bors

src/librustc/metadata/encoder.rs

@@ -799,7 +799,7 @@ fn encode_info_for_method(ecx: &EncodeContext,
         } else {
             encode_symbol(ecx, ebml_w, m.def_id.node);
         }
-        encode_method_argument_names(ebml_w, &*ast_method.decl);
+        encode_method_argument_names(ebml_w, method_fn_decl(&*ast_method));
     }
 
     ebml_w.end_tag();
@@ -1241,7 +1241,7 @@ fn encode_info_for_item(ecx: &EncodeContext,
                     encode_method_sort(ebml_w, 'p');
                     encode_inlined_item(ecx, ebml_w,
                                         IIMethodRef(def_id, true, &*m));
-                    encode_method_argument_names(ebml_w, &*m.decl);
+                    encode_method_argument_names(ebml_w, method_fn_decl(m));
                 }
             }
 

src/librustc/middle/astencode.rs

@@ -136,7 +136,7 @@ pub fn decode_inlined_item(cdata: &cstore::crate_metadata,
         let ident = match ii {
             ast::IIItem(i) => i.ident,
             ast::IIForeign(i) => i.ident,
-            ast::IIMethod(_, _, m) => m.ident,
+            ast::IIMethod(_, _, m) => ast_util::method_ident(&*m),
         };
         debug!("Fn named: {}", token::get_ident(ident));
         debug!("< Decoded inlined fn: {}::{}",
@@ -345,7 +345,9 @@ fn simplify_ast(ii: e::InlinedItemRef) -> ast::InlinedItem {
         // HACK we're not dropping items.
         e::IIItemRef(i) => ast::IIItem(fold::noop_fold_item(i, &mut fld)
                                        .expect_one("expected one item")),
-        e::IIMethodRef(d, p, m) => ast::IIMethod(d, p, fold::noop_fold_method(m, &mut fld)),
+        e::IIMethodRef(d, p, m) => ast::IIMethod(d, p, fold::noop_fold_method(m, &mut fld)
+                                                 .expect_one(
+                "noop_fold_method must produce exactly one method")),
         e::IIForeignRef(i) => ast::IIForeign(fold::noop_fold_foreign_item(i, &mut fld))
     }
 }
@@ -387,7 +389,8 @@ fn renumber_and_map_ast(xcx: &ExtendedDecodeContext,
                 ast::IIItem(fld.fold_item(i).expect_one("expected one item"))
             }
             ast::IIMethod(d, is_provided, m) => {
-                ast::IIMethod(xcx.tr_def_id(d), is_provided, fld.fold_method(m))
+                ast::IIMethod(xcx.tr_def_id(d), is_provided, fld.fold_method(m)
+                              .expect_one("expected one method"))
             }
             ast::IIForeign(i) => ast::IIForeign(fld.fold_foreign_item(i))
         }

src/librustc/middle/dead.rs

@@ -22,6 +22,7 @@ use util::nodemap::NodeSet;
 use std::collections::HashSet;
 use syntax::ast;
 use syntax::ast_map;
+use syntax::ast_util;
 use syntax::ast_util::{local_def, is_local};
 use syntax::attr::AttrMetaMethods;
 use syntax::attr;
@@ -212,7 +213,7 @@ impl<'a> MarkSymbolVisitor<'a> {
                 visit::walk_trait_method(self, &*trait_method, ctxt);
             }
             ast_map::NodeMethod(method) => {
-                visit::walk_block(self, &*method.body, ctxt);
+                visit::walk_block(self, ast_util::method_body(&*method), ctxt);
             }
             ast_map::NodeForeignItem(foreign_item) => {
                 visit::walk_foreign_item(self, &*foreign_item, ctxt);
@@ -520,7 +521,8 @@ impl<'a> Visitor<()> for DeadVisitor<'a> {
     // Overwrite so that we don't warn the trait method itself.
     fn visit_trait_method(&mut self, trait_method: &ast::TraitMethod, _: ()) {
         match *trait_method {
-            ast::Provided(ref method) => visit::walk_block(self, &*method.body, ()),
+            ast::Provided(ref method) => visit::walk_block(self,
+                                                           ast_util::method_body(&**method), ()),
             ast::Required(_) => ()
         }
     }

src/librustc/middle/effect.rs

@@ -17,6 +17,7 @@ use middle::typeck::MethodCall;
 use util::ppaux;
 
 use syntax::ast;
+use syntax::ast_util;
 use syntax::codemap::Span;
 use syntax::visit;
 use syntax::visit::Visitor;
@@ -94,7 +95,7 @@ impl<'a> Visitor<()> for EffectCheckVisitor<'a> {
             visit::FkItemFn(_, _, fn_style, _) =>
                 (true, fn_style == ast::UnsafeFn),
             visit::FkMethod(_, _, method) =>
-                (true, method.fn_style == ast::UnsafeFn),
+                (true, ast_util::method_fn_style(method) == ast::UnsafeFn),
             _ => (false, false),
         };
 

src/librustc/middle/privacy.rs

@@ -26,6 +26,7 @@ use util::nodemap::{NodeMap, NodeSet};
 
 use syntax::ast;
 use syntax::ast_map;
+use syntax::ast_util;
 use syntax::ast_util::{is_local, local_def};
 use syntax::attr;
 use syntax::codemap::Span;
@@ -263,10 +264,10 @@ impl<'a> Visitor<()> for EmbargoVisitor<'a> {
 
                 if public_ty || public_trait {
                     for method in methods.iter() {
-                        let meth_public = match method.explicit_self.node {
+                        let meth_public = match ast_util::method_explicit_self(&**method).node {
                             ast::SelfStatic => public_ty,
                             _ => true,
-                        } && method.vis == ast::Public;
+                        } && ast_util::method_vis(&**method) == ast::Public;
                         if meth_public || tr.is_some() {
                             self.exported_items.insert(method.id);
                         }
@@ -456,8 +457,8 @@ impl<'a> PrivacyVisitor<'a> {
                     let imp = self.tcx.map.get_parent_did(closest_private_id);
                     match ty::impl_trait_ref(self.tcx, imp) {
                         Some(..) => return Allowable,
-                        _ if m.vis == ast::Public => return Allowable,
-                        _ => m.vis
+                        _ if ast_util::method_vis(&**m) == ast::Public => return Allowable,
+                        _ => ast_util::method_vis(&**m)
                     }
                 }
                 Some(ast_map::NodeTraitMethod(_)) => {
@@ -1078,7 +1079,7 @@ impl<'a> SanePrivacyVisitor<'a> {
                                 "visibility qualifiers have no effect on trait \
                                  impls");
                 for m in methods.iter() {
-                    check_inherited(m.span, m.vis, "");
+                    check_inherited(m.span, ast_util::method_vis(&**m), "");
                 }
             }
 
@@ -1110,7 +1111,7 @@ impl<'a> SanePrivacyVisitor<'a> {
                 for m in methods.iter() {
                     match *m {
                         ast::Provided(ref m) => {
-                            check_inherited(m.span, m.vis,
+                            check_inherited(m.span, ast_util::method_vis(&**m),
                                             "unnecessary visibility");
                         }
                         ast::Required(ref m) => {
@@ -1148,7 +1149,7 @@ impl<'a> SanePrivacyVisitor<'a> {
         match item.node {
             ast::ItemImpl(_, _, _, ref methods) => {
                 for m in methods.iter() {
-                    check_inherited(tcx, m.span, m.vis);
+                    check_inherited(tcx, m.span, ast_util::method_vis(&**m));
                 }
             }
             ast::ItemForeignMod(ref fm) => {
@@ -1174,7 +1175,7 @@ impl<'a> SanePrivacyVisitor<'a> {
                     match *m {
                         ast::Required(..) => {}
                         ast::Provided(ref m) => check_inherited(tcx, m.span,
-                                                                m.vis),
+                                                                ast_util::method_vis(&**m)),
                     }
                 }
             }
@@ -1344,7 +1345,7 @@ impl<'a> Visitor<()> for VisiblePrivateTypesVisitor<'a> {
                     // methods will be visible as `Public::foo`.
                     let mut found_pub_static = false;
                     for method in methods.iter() {
-                        if method.explicit_self.node == ast::SelfStatic &&
+                        if ast_util::method_explicit_self(&**method).node == ast::SelfStatic &&
                             self.exported_items.contains(&method.id) {
                             found_pub_static = true;
                             visit::walk_method_helper(self, &**method, ());

src/librustc/middle/reachable.rs

@@ -68,7 +68,7 @@ fn item_might_be_inlined(item: &ast::Item) -> bool {
 fn method_might_be_inlined(tcx: &ty::ctxt, method: &ast::Method,
                            impl_src: ast::DefId) -> bool {
     if attributes_specify_inlining(method.attrs.as_slice()) ||
-        generics_require_inlining(&method.generics) {
+        generics_require_inlining(ast_util::method_generics(&*method)) {
         return true
     }
     if is_local(impl_src) {
@@ -200,7 +200,7 @@ impl<'a> ReachableContext<'a> {
                 }
             }
             Some(ast_map::NodeMethod(method)) => {
-                if generics_require_inlining(&method.generics) ||
+                if generics_require_inlining(ast_util::method_generics(&*method)) ||
                         attributes_specify_inlining(method.attrs.as_slice()) {
                     true
                 } else {
@@ -316,14 +316,14 @@ impl<'a> ReachableContext<'a> {
                         // Keep going, nothing to get exported
                     }
                     ast::Provided(ref method) => {
-                        visit::walk_block(self, &*method.body, ())
+                        visit::walk_block(self, ast_util::method_body(&**method), ())
                     }
                 }
             }
             ast_map::NodeMethod(method) => {
                 let did = self.tcx.map.get_parent_did(search_item);
                 if method_might_be_inlined(self.tcx, &*method, did) {
-                    visit::walk_block(self, &*method.body, ())
+                    visit::walk_block(self, ast_util::method_body(&*method), ())
                 }
             }
             // Nothing to recurse on for these

src/librustc/middle/resolve.rs

@@ -22,6 +22,7 @@ use util::nodemap::{NodeMap, DefIdSet, FnvHashMap};
 
 use syntax::ast::*;
 use syntax::ast;
+use syntax::ast_util;
 use syntax::ast_util::{local_def};
 use syntax::ast_util::{walk_pat, trait_method_to_ty_method};
 use syntax::ext::mtwt;
@@ -1298,20 +1299,20 @@ impl<'a> Resolver<'a> {
                         // For each method...
                         for method in methods.iter() {
                             // Add the method to the module.
-                            let ident = method.ident;
+                            let ident = ast_util::method_ident(&**method);
                             let method_name_bindings =
                                 self.add_child(ident,
                                                new_parent.clone(),
                                                ForbidDuplicateValues,
                                                method.span);
-                            let def = match method.explicit_self.node {
+                            let def = match ast_util::method_explicit_self(&**method).node {
                                 SelfStatic => {
                                     // Static methods become
                                     // `def_static_method`s.
                                     DefStaticMethod(local_def(method.id),
                                                       FromImpl(local_def(
                                                         item.id)),
-                                                      method.fn_style)
+                                                    ast_util::method_fn_style(&**method))
                                 }
                                 _ => {
                                     // Non-static methods become
@@ -1320,7 +1321,7 @@ impl<'a> Resolver<'a> {
                                 }
                             };
 
-                            let is_public = method.vis == ast::Public;
+                            let is_public = ast_util::method_vis(&**method) == ast::Public;
                             method_name_bindings.define_value(def,
                                                               method.span,
                                                               is_public);
@@ -4003,13 +4004,15 @@ impl<'a> Resolver<'a> {
     fn resolve_method(&mut self,
                       rib_kind: RibKind,
                       method: &Method) {
-        let method_generics = &method.generics;
+        let method_generics = ast_util::method_generics(method);
         let type_parameters = HasTypeParameters(method_generics,
                                                 FnSpace,
                                                 method.id,
                                                 rib_kind);
 
-        self.resolve_function(rib_kind, Some(method.decl), type_parameters, method.body);
+        self.resolve_function(rib_kind, Some(ast_util::method_fn_decl(method)),
+                              type_parameters,
+                              ast_util::method_body(method));
     }
 
     fn with_current_self_type<T>(&mut self, self_type: &Ty, f: |&mut Resolver| -> T) -> T {
@@ -4080,7 +4083,7 @@ impl<'a> Resolver<'a> {
     fn check_trait_method(&self, method: &Method) {
         // If there is a TraitRef in scope for an impl, then the method must be in the trait.
         for &(did, ref trait_ref) in self.current_trait_ref.iter() {
-            let method_name = method.ident.name;
+            let method_name = ast_util::method_ident(method).name;
 
             if self.method_map.borrow().find(&(method_name, did)).is_none() {
                 let path_str = self.path_idents_to_string(&trait_ref.path);

src/librustc/middle/save/mod.rs

@@ -333,7 +333,7 @@ impl <'l> DxrVisitor<'l> {
             },
         };
 
-        qualname.push_str(get_ident(method.ident).get());
+        qualname.push_str(get_ident(ast_util::method_ident(&*method)).get());
         let qualname = qualname.as_slice();
 
         // record the decl for this def (if it has one)
@@ -349,17 +349,18 @@ impl <'l> DxrVisitor<'l> {
                             decl_id,
                             scope_id);
 
-        self.process_formals(&method.decl.inputs, qualname, e);
+        let m_decl = ast_util::method_fn_decl(&*method);
+        self.process_formals(&m_decl.inputs, qualname, e);
 
         // walk arg and return types
-        for arg in method.decl.inputs.iter() {
+        for arg in m_decl.inputs.iter() {
             self.visit_ty(&*arg.ty, e);
         }
-        self.visit_ty(&*method.decl.output, e);
+        self.visit_ty(m_decl.output, e);
         // walk the fn body
-        self.visit_block(&*method.body, DxrVisitorEnv::new_nested(method.id));
+        self.visit_block(ast_util::method_body(&*method), DxrVisitorEnv::new_nested(method.id));
 
-        self.process_generic_params(&method.generics,
+        self.process_generic_params(ast_util::method_generics(&*method),
                                     method.span,
                                     qualname,
                                     method.id,

src/librustc/middle/trans/debuginfo.rs

@@ -1138,10 +1138,10 @@ pub fn create_function_debug_context(cx: &CrateContext,
             }
         }
         ast_map::NodeMethod(ref method) => {
-            (method.ident,
-             method.decl,
-             &method.generics,
-             method.body,
+            (ast_util::method_ident(&**method),
+             ast_util::method_fn_decl(&**method),
+             ast_util::method_generics(&**method),
+             ast_util::method_body(&**method),
              method.span,
              true)
         }
@@ -1167,10 +1167,10 @@ pub fn create_function_debug_context(cx: &CrateContext,
         ast_map::NodeTraitMethod(ref trait_method) => {
             match **trait_method {
                 ast::Provided(ref method) => {
-                    (method.ident,
-                     method.decl,
-                     &method.generics,
-                     method.body,
+                    (ast_util::method_ident(&**method),
+                     ast_util::method_fn_decl(&**method),
+                     ast_util::method_generics(&**method),
+                     ast_util::method_body(&**method),
                      method.span,
                      true)
                 }

src/librustc/middle/trans/inline.rs

@@ -128,11 +128,12 @@ pub fn maybe_instantiate_inline(ccx: &CrateContext, fn_id: ast::DefId)
             let impl_tpt = ty::lookup_item_type(ccx.tcx(), impl_did);
             let unparameterized =
                 impl_tpt.generics.types.is_empty() &&
-                mth.generics.ty_params.is_empty();
+                ast_util::method_generics(&*mth).ty_params.is_empty();
 
           if unparameterized {
               let llfn = get_item_val(ccx, mth.id);
-              trans_fn(ccx, &*mth.decl, &*mth.body, llfn,
+              trans_fn(ccx, ast_util::method_fn_decl(&*mth),
+                       ast_util::method_body(&*mth), llfn,
                        &param_substs::empty(), mth.id, []);
           }
           local_def(mth.id)