Rollup merge of #39953 - keeperofdakeys:macro-error, r=jseyfried

Provide suggestions for unknown macros imported with `use`

cc https://github.com/rust-lang/rust/issues/30197

r? @jseyfried

src/librustc/hir/def.rs

@@ -11,6 +11,7 @@
 use hir::def_id::DefId;
 use util::nodemap::NodeMap;
 use syntax::ast;
+use syntax::ext::base::MacroKind;
 use hir;
 
 #[derive(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
@@ -53,7 +54,7 @@ pub enum Def {
     Label(ast::NodeId),
 
     // Macro namespace
-    Macro(DefId),
+    Macro(DefId, MacroKind),
 
     // Both namespaces
     Err,
@@ -141,7 +142,7 @@ impl Def {
             Def::Variant(id) | Def::VariantCtor(id, ..) | Def::Enum(id) | Def::TyAlias(id) |
             Def::AssociatedTy(id) | Def::TyParam(id) | Def::Struct(id) | Def::StructCtor(id, ..) |
             Def::Union(id) | Def::Trait(id) | Def::Method(id) | Def::Const(id) |
-            Def::AssociatedConst(id) | Def::Local(id) | Def::Upvar(id, ..) | Def::Macro(id) => {
+            Def::AssociatedConst(id) | Def::Local(id) | Def::Upvar(id, ..) | Def::Macro(id, ..) => {
                 id
             }
 

src/librustc_metadata/decoder.rs

@@ -39,6 +39,7 @@ use rustc_serialize::{Decodable, Decoder, SpecializedDecoder, opaque};
 use syntax::attr;
 use syntax::ast;
 use syntax::codemap;
+use syntax::ext::base::MacroKind;
 use syntax_pos::{self, Span, BytePos, Pos, DUMMY_SP};
 
 pub struct DecodeContext<'a, 'tcx: 'a> {
@@ -434,7 +435,7 @@ impl<'tcx> EntryKind<'tcx> {
             EntryKind::Variant(_) => Def::Variant(did),
             EntryKind::Trait(_) => Def::Trait(did),
             EntryKind::Enum(..) => Def::Enum(did),
-            EntryKind::MacroDef(_) => Def::Macro(did),
+            EntryKind::MacroDef(_) => Def::Macro(did, MacroKind::Bang),
 
             EntryKind::ForeignMod |
             EntryKind::Impl(_) |
@@ -483,9 +484,11 @@ impl<'a, 'tcx> CrateMetadata {
     }
 
     pub fn get_def(&self, index: DefIndex) -> Option<Def> {
-        match self.is_proc_macro(index) {
-            true => Some(Def::Macro(self.local_def_id(index))),
-            false => self.entry(index).kind.to_def(self.local_def_id(index)),
+        if !self.is_proc_macro(index) {
+            self.entry(index).kind.to_def(self.local_def_id(index))
+        } else {
+            let kind = self.proc_macros.as_ref().unwrap()[index.as_usize() - 1].1.kind();
+            Some(Def::Macro(self.local_def_id(index), kind))
         }
     }
 
@@ -688,8 +691,14 @@ impl<'a, 'tcx> CrateMetadata {
     {
         if let Some(ref proc_macros) = self.proc_macros {
             if id == CRATE_DEF_INDEX {
-                for (id, &(name, _)) in proc_macros.iter().enumerate() {
-                    let def = Def::Macro(DefId { krate: self.cnum, index: DefIndex::new(id + 1) });
+                for (id, &(name, ref ext)) in proc_macros.iter().enumerate() {
+                    let def = Def::Macro(
+                        DefId {
+                            krate: self.cnum,
+                            index: DefIndex::new(id + 1)
+                        },
+                        ext.kind()
+                    );
                     callback(def::Export { name: name, def: def });
                 }
             }

src/librustc_resolve/build_reduced_graph.rs

@@ -495,7 +495,7 @@ impl<'a> Resolver<'a> {
 
     pub fn get_macro(&mut self, def: Def) -> Rc<SyntaxExtension> {
         let def_id = match def {
-            Def::Macro(def_id) => def_id,
+            Def::Macro(def_id, ..) => def_id,
             _ => panic!("Expected Def::Macro(..)"),
         };
         if let Some(ext) = self.macro_map.get(&def_id) {
@@ -537,7 +537,6 @@ impl<'a> Resolver<'a> {
                            binding: &'a NameBinding<'a>,
                            span: Span,
                            allow_shadowing: bool) {
-        self.macro_names.insert(name);
         if self.builtin_macros.insert(name, binding).is_some() && !allow_shadowing {
             let msg = format!("`{}` is already in scope", name);
             let note =

src/librustc_resolve/lib.rs

@@ -1265,7 +1265,7 @@ impl<'a> Resolver<'a> {
             ribs: PerNS {
                 value_ns: vec![Rib::new(ModuleRibKind(graph_root))],
                 type_ns: vec![Rib::new(ModuleRibKind(graph_root))],
-                macro_ns: None,
+                macro_ns: Some(vec![Rib::new(ModuleRibKind(graph_root))]),
             },
             label_ribs: Vec::new(),
 
@@ -2328,10 +2328,13 @@ impl<'a> Resolver<'a> {
                 };
             }
         }
-        if primary_ns != MacroNS && path.len() == 1 &&
-                self.macro_names.contains(&path[0].name) {
+        let is_builtin = self.builtin_macros.get(&path[0].name).cloned()
+            .map(|binding| binding.get_macro(self).kind() == MacroKind::Bang).unwrap_or(false);
+        if primary_ns != MacroNS && (is_builtin || self.macro_names.contains(&path[0].name)) {
             // Return some dummy definition, it's enough for error reporting.
-            return Some(PathResolution::new(Def::Macro(DefId::local(CRATE_DEF_INDEX))));
+            return Some(
+                PathResolution::new(Def::Macro(DefId::local(CRATE_DEF_INDEX), MacroKind::Bang))
+            );
         }
         fin_res
     }

src/librustc_resolve/macros.rs

@@ -23,7 +23,7 @@ use syntax::ast::{self, Name, Ident};
 use syntax::attr;
 use syntax::errors::DiagnosticBuilder;
 use syntax::ext::base::{self, Determinacy, MultiModifier, MultiDecorator};
-use syntax::ext::base::{NormalTT, Resolver as SyntaxResolver, SyntaxExtension};
+use syntax::ext::base::{Resolver as SyntaxResolver, SyntaxExtension};
 use syntax::ext::base::MacroKind;
 use syntax::ext::expand::{Expansion, mark_tts};
 use syntax::ext::hygiene::Mark;
@@ -152,16 +152,14 @@ impl<'a> base::Resolver for Resolver<'a> {
     }
 
     fn add_ext(&mut self, ident: ast::Ident, ext: Rc<SyntaxExtension>) {
-        if let NormalTT(..) = *ext {
-            self.macro_names.insert(ident.name);
-        }
         let def_id = DefId {
             krate: BUILTIN_MACROS_CRATE,
             index: DefIndex::new(self.macro_map.len()),
         };
+        let kind = ext.kind();
         self.macro_map.insert(def_id, ext);
         let binding = self.arenas.alloc_name_binding(NameBinding {
-            kind: NameBindingKind::Def(Def::Macro(def_id)),
+            kind: NameBindingKind::Def(Def::Macro(def_id, kind)),
             span: DUMMY_SP,
             vis: ty::Visibility::Invisible,
             expansion: Mark::root(),
@@ -470,24 +468,40 @@ impl<'a> Resolver<'a> {
 
     fn suggest_macro_name(&mut self, name: &str, kind: MacroKind,
                           err: &mut DiagnosticBuilder<'a>) {
-        let suggestion = match kind {
-            MacroKind::Bang =>
-                find_best_match_for_name(self.macro_names.iter(), name, None),
-            MacroKind::Attr |
-            MacroKind::Derive => {
-                // Find a suggestion from the legacy namespace.
-                // FIXME: get_macro needs an &mut Resolver, can we do it without cloning?
-                let builtin_macros = self.builtin_macros.clone();
-                let names = builtin_macros.iter().filter_map(|(name, binding)| {
-                    if binding.get_macro(self).kind() == kind {
-                        Some(name)
-                    } else {
-                        None
-                    }
-                });
-                find_best_match_for_name(names, name, None)
+        // First check if this is a locally-defined bang macro.
+        let suggestion = if let MacroKind::Bang = kind {
+            find_best_match_for_name(self.macro_names.iter(), name, None)
+        } else {
+            None
+        // Then check builtin macros.
+        }.or_else(|| {
+            // FIXME: get_macro needs an &mut Resolver, can we do it without cloning?
+            let builtin_macros = self.builtin_macros.clone();
+            let names = builtin_macros.iter().filter_map(|(name, binding)| {
+                if binding.get_macro(self).kind() == kind {
+                    Some(name)
+                } else {
+                    None
+                }
+            });
+            find_best_match_for_name(names, name, None)
+        // Then check modules.
+        }).or_else(|| {
+            if !self.use_extern_macros {
+                return None;
             }
-        };
+            let is_macro = |def| {
+                if let Def::Macro(_, def_kind) = def {
+                    def_kind == kind
+                } else {
+                    false
+                }
+            };
+            let ident = Ident::from_str(name);
+            self.lookup_typo_candidate(&vec![ident], MacroNS, is_macro)
+                .as_ref().map(|s| Symbol::intern(s))
+        });
+
         if let Some(suggestion) = suggestion {
             if suggestion != name {
                 if let MacroKind::Bang = kind {
@@ -566,7 +580,7 @@ impl<'a> Resolver<'a> {
             });
             self.macro_exports.push(Export {
                 name: def.ident.name,
-                def: Def::Macro(self.definitions.local_def_id(def.id)),
+                def: Def::Macro(self.definitions.local_def_id(def.id), MacroKind::Bang),
             });
             self.exported_macros.push(def);
         }

src/librustc_save_analysis/dump_visitor.rs

@@ -336,7 +336,7 @@ impl<'l, 'tcx: 'l, 'll, D: Dump + 'll> DumpVisitor<'l, 'tcx, 'll, D> {
             Def::AssociatedTy(..) |
             Def::AssociatedConst(..) |
             Def::PrimTy(_) |
-            Def::Macro(_) |
+            Def::Macro(..) |
             Def::Err => {
                span_bug!(span,
                          "process_def_kind for unexpected item: {:?}",

src/librustdoc/visit_ast.rs

@@ -199,7 +199,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
         self.inside_public_path = orig_inside_public_path;
         if let Some(exports) = self.cx.export_map.get(&id) {
             for export in exports {
-                if let Def::Macro(def_id) = export.def {
+                if let Def::Macro(def_id, ..) = export.def {
                     if def_id.krate == LOCAL_CRATE {
                         continue // These are `krate.exported_macros`, handled in `self.visit()`.
                     }

src/libsyntax/ext/base.rs

@@ -475,7 +475,7 @@ pub type BuiltinDeriveFn =
     for<'cx> fn(&'cx mut ExtCtxt, Span, &MetaItem, &Annotatable, &mut FnMut(Annotatable));
 
 /// Represents different kinds of macro invocations that can be resolved.
-#[derive(Clone, Copy, PartialEq, Eq)]
+#[derive(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub enum MacroKind {
     /// A bang macro - foo!()
     Bang,

src/test/compile-fail-fulldeps/proc-macro/resolve-error.rs

@@ -22,15 +22,24 @@ extern crate attr_proc_macro;
 
 use attr_proc_macro::attr_proc_macro;
 
-#[derive(FooWithLongNam)]
-//~^ ERROR cannot find derive macro `FooWithLongNam` in this scope
+macro_rules! FooWithLongNam {
+    () => {}
+}
+
+#[derive(FooWithLongNan)]
+//~^ ERROR cannot find derive macro `FooWithLongNan` in this scope
 //~^^ HELP did you mean `FooWithLongName`?
 struct Foo;
 
 #[attr_proc_macra]
 //~^ ERROR cannot find attribute macro `attr_proc_macra` in this scope
+//~^^ HELP did you mean `attr_proc_macro`?
 struct Bar;
 
+#[FooWithLongNan]
+//~^ ERROR cannot find attribute macro `FooWithLongNan` in this scope
+struct Asdf;
+
 #[derive(Dlone)]
 //~^ ERROR cannot find derive macro `Dlone` in this scope
 //~^^ HELP did you mean `Clone`?
@@ -41,4 +50,18 @@ struct A;
 //~^^ HELP did you mean `Clona`?
 struct B;
 
-fn main() {}
+#[derive(attr_proc_macra)]
+//~^ ERROR cannot find derive macro `attr_proc_macra` in this scope
+struct C;
+
+fn main() {
+    FooWithLongNama!();
+    //~^ ERROR cannot find macro `FooWithLongNama!` in this scope
+    //~^^ HELP did you mean `FooWithLongNam!`?
+
+    attr_proc_macra!();
+    //~^ ERROR cannot find macro `attr_proc_macra!` in this scope
+
+    Dlona!();
+    //~^ ERROR cannot find macro `Dlona!` in this scope
+}