syntax: Do not accidentally treat multi-segment meta-items as single-segment

3 files changed, 32 insertions, 28 deletions

diff --git a/src/libsyntax_ext/deriving/custom.rs b/src/libsyntax_ext/deriving/custom.rs
index cfc3c931598..e73110717e9 100644
--- a/src/libsyntax_ext/deriving/custom.rs
+++ b/src/libsyntax_ext/deriving/custom.rs
@@ -17,9 +17,11 @@ struct MarkAttrs<'a>(&'a [ast::Name]);
 
 impl<'a> Visitor<'a> for MarkAttrs<'a> {
     fn visit_attribute(&mut self, attr: &Attribute) {
-        if self.0.contains(&attr.name()) {
-            mark_used(attr);
-            mark_known(attr);
+        if let Some(ident) = attr.ident() {
+            if self.0.contains(&ident.name) {
+                mark_used(attr);
+                mark_known(attr);
+            }
         }
     }
 
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index b8f96c5bc0e..2bb98c1bf62 100644
--- a/src/libsyntax_ext/deriving/generic/mod.rs
+++ b/src/libsyntax_ext/deriving/generic/mod.rs
@@ -463,12 +463,9 @@ impl<'a> TraitDef<'a> {
                 let mut attrs = newitem.attrs.clone();
                 attrs.extend(item.attrs
                     .iter()
-                    .filter(|a| {
-                        match &*a.name().as_str() {
-                            "allow" | "warn" | "deny" | "forbid" | "stable" | "unstable" => true,
-                            _ => false,
-                        }
-                    })
+                    .filter(|a| a.ident_str().map_or(false, |name| {
+                        ["allow", "warn", "deny", "forbid", "stable", "unstable"].contains(&name)
+                    }))
                     .cloned());
                 push(Annotatable::Item(P(ast::Item { attrs: attrs, ..(*newitem).clone() })))
             }
diff --git a/src/libsyntax_ext/proc_macro_decls.rs b/src/libsyntax_ext/proc_macro_decls.rs
index d8f8decef39..4cd42d6d755 100644
--- a/src/libsyntax_ext/proc_macro_decls.rs
+++ b/src/libsyntax_ext/proc_macro_decls.rs
@@ -113,24 +113,27 @@ impl<'a> CollectProcMacros<'a> {
                                   "attribute must have either one or two arguments");
             return
         }
-        let trait_attr = &list[0];
-        let attributes_attr = list.get(1);
-        let trait_name = match trait_attr.name() {
-            Some(name) => name,
+        let trait_attr = match list[0].meta_item() {
+            Some(meta_item) => meta_item,
             _ => {
-                self.handler.span_err(trait_attr.span(), "not a meta item");
+                self.handler.span_err(list[0].span(), "not a meta item");
+                return
+            }
+        };
+        let trait_ident = match trait_attr.ident() {
+            Some(trait_ident) if trait_attr.is_word() => trait_ident,
+            _ => {
+                self.handler.span_err(trait_attr.span, "must only be one word");
                 return
             }
         };
-        if !trait_attr.is_word() {
-            self.handler.span_err(trait_attr.span(), "must only be one word");
-        }
 
-        if deriving::is_builtin_trait(trait_name) {
-            self.handler.span_err(trait_attr.span(),
+        if deriving::is_builtin_trait(trait_ident.name) {
+            self.handler.span_err(trait_attr.span,
                                   "cannot override a built-in #[derive] mode");
         }
 
+        let attributes_attr = list.get(1);
         let proc_attrs: Vec<_> = if let Some(attr) = attributes_attr {
             if !attr.check_name("attributes") {
                 self.handler.span_err(attr.span(), "second argument must be `attributes`")
@@ -141,20 +144,22 @@ impl<'a> CollectProcMacros<'a> {
                                        `attributes(foo, bar)`");
                 &[]
             }).into_iter().filter_map(|attr| {
-                let name = match attr.name() {
-                    Some(name) => name,
+                let attr = match attr.meta_item() {
+                    Some(meta_item) => meta_item,
                     _ => {
                         self.handler.span_err(attr.span(), "not a meta item");
                         return None;
                     },
                 };
 
-                if !attr.is_word() {
-                    self.handler.span_err(attr.span(), "must only be one word");
-                    return None;
-                }
-
-                Some(name)
+                let ident = match attr.ident() {
+                    Some(ident) if attr.is_word() => ident,
+                    _ => {
+                        self.handler.span_err(attr.span, "must only be one word");
+                        return None;
+                    }
+                };
+                Some(ident.name)
             }).collect()
         } else {
             Vec::new()
@@ -163,7 +168,7 @@ impl<'a> CollectProcMacros<'a> {
         if self.in_root && item.vis.node.is_pub() {
             self.derives.push(ProcMacroDerive {
                 span: item.span,
-                trait_name,
+                trait_name: trait_ident.name,
                 function_name: item.ident,
                 attrs: proc_attrs,
             });