1 files changed, 322 insertions, 315 deletions

diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index fd8245113..b9f40d3dd 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -4,14 +4,15 @@
 //! resolves imports and expands macros.
 
 use hir_expand::{
+    builtin_derive::find_builtin_derive,
     builtin_macro::find_builtin_macro,
-    name::{self, AsName, Name},
-    HirFileId, MacroCallId, MacroDefId, MacroDefKind, MacroFileKind,
+    name::{name, AsName, Name},
+    HirFileId, MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
 };
 use ra_cfg::CfgOptions;
 use ra_db::{CrateId, FileId};
 use ra_syntax::ast;
-use rustc_hash::{FxHashMap, FxHashSet};
+use rustc_hash::FxHashMap;
 use test_utils::tested_by;
 
 use crate::{
@@ -19,13 +20,12 @@ use crate::{
     db::DefDatabase,
     nameres::{
         diagnostics::DefDiagnostic, mod_resolution::ModDir, path_resolution::ReachedFixedPoint,
-        raw, CrateDefMap, ModuleData, Resolution, ResolveMode,
+        raw, BuiltinShadowMode, CrateDefMap, ModuleData, ModuleOrigin, ResolveMode,
     },
-    path::{Path, PathKind},
+    path::{ModPath, PathKind},
     per_ns::PerNs,
-    AdtId, AstId, AstItemDef, ConstLoc, ContainerId, EnumId, EnumVariantId, FunctionLoc, ImplId,
-    Intern, LocalImportId, LocalModuleId, LocationCtx, ModuleDefId, ModuleId, StaticLoc, StructId,
-    TraitId, TypeAliasLoc, UnionId,
+    AdtId, AstId, ConstLoc, ContainerId, EnumLoc, EnumVariantId, FunctionLoc, ImplLoc, Intern,
+    LocalModuleId, ModuleDefId, ModuleId, StaticLoc, StructLoc, TraitLoc, TypeAliasLoc, UnionLoc,
 };
 
 pub(super) fn collect_defs(db: &impl DefDatabase, mut def_map: CrateDefMap) -> CrateDefMap {
@@ -57,68 +57,63 @@ pub(super) fn collect_defs(db: &impl DefDatabase, mut def_map: CrateDefMap) -> C
         def_map,
         glob_imports: FxHashMap::default(),
         unresolved_imports: Vec::new(),
+        resolved_imports: Vec::new(),
+
         unexpanded_macros: Vec::new(),
+        unexpanded_attribute_macros: Vec::new(),
         mod_dirs: FxHashMap::default(),
-        macro_stack_monitor: MacroStackMonitor::default(),
-        poison_macros: FxHashSet::default(),
         cfg_options,
     };
     collector.collect();
     collector.finish()
 }
 
-#[derive(Default)]
-struct MacroStackMonitor {
-    counts: FxHashMap<MacroDefId, u32>,
-
-    /// Mainly use for test
-    validator: Option<Box<dyn Fn(u32) -> bool>>,
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+enum PartialResolvedImport {
+    /// None of any namespaces is resolved
+    Unresolved,
+    /// One of namespaces is resolved
+    Indeterminate(PerNs),
+    /// All namespaces are resolved, OR it is came from other crate
+    Resolved(PerNs),
 }
 
-impl MacroStackMonitor {
-    fn increase(&mut self, macro_def_id: MacroDefId) {
-        *self.counts.entry(macro_def_id).or_default() += 1;
-    }
-
-    fn decrease(&mut self, macro_def_id: MacroDefId) {
-        *self.counts.entry(macro_def_id).or_default() -= 1;
+impl PartialResolvedImport {
+    fn namespaces(&self) -> PerNs {
+        match self {
+            PartialResolvedImport::Unresolved => PerNs::none(),
+            PartialResolvedImport::Indeterminate(ns) => *ns,
+            PartialResolvedImport::Resolved(ns) => *ns,
+        }
     }
+}
 
-    fn is_poison(&self, macro_def_id: MacroDefId) -> bool {
-        let cur = *self.counts.get(&macro_def_id).unwrap_or(&0);
+#[derive(Clone, Debug, Eq, PartialEq)]
+struct ImportDirective {
+    module_id: LocalModuleId,
+    import_id: raw::Import,
+    import: raw::ImportData,
+    status: PartialResolvedImport,
+}
 
-        if let Some(validator) = &self.validator {
-            validator(cur)
-        } else {
-            cur > 100
-        }
-    }
+#[derive(Clone, Debug, Eq, PartialEq)]
+struct MacroDirective {
+    module_id: LocalModuleId,
+    ast_id: AstId<ast::MacroCall>,
+    path: ModPath,
+    legacy: Option<MacroCallId>,
 }
 
 /// Walks the tree of module recursively
 struct DefCollector<'a, DB> {
     db: &'a DB,
     def_map: CrateDefMap,
-    glob_imports: FxHashMap<LocalModuleId, Vec<(LocalModuleId, LocalImportId)>>,
-    unresolved_imports: Vec<(LocalModuleId, LocalImportId, raw::ImportData)>,
-    unexpanded_macros: Vec<(LocalModuleId, AstId<ast::MacroCall>, Path)>,
+    glob_imports: FxHashMap<LocalModuleId, Vec<(LocalModuleId, raw::Import)>>,
+    unresolved_imports: Vec<ImportDirective>,
+    resolved_imports: Vec<ImportDirective>,
+    unexpanded_macros: Vec<MacroDirective>,
+    unexpanded_attribute_macros: Vec<(LocalModuleId, AstId<ast::ModuleItem>, ModPath)>,
     mod_dirs: FxHashMap<LocalModuleId, ModDir>,
-
-    /// Some macro use `$tt:tt which mean we have to handle the macro perfectly
-    /// To prevent stack overflow, we add a deep counter here for prevent that.
-    macro_stack_monitor: MacroStackMonitor,
-    /// Some macros are not well-behavior, which leads to infinite loop
-    /// e.g. macro_rules! foo { ($ty:ty) => { foo!($ty); } }
-    /// We mark it down and skip it in collector
-    ///
-    /// FIXME:
-    /// Right now it only handle a poison macro in a single crate,
-    /// such that if other crate try to call that macro,
-    /// the whole process will do again until it became poisoned in that crate.
-    /// We should handle this macro set globally
-    /// However, do we want to put it as a global variable?
-    poison_macros: FxHashSet<MacroDefId>,
-
     cfg_options: &'a CfgOptions,
 }
 
@@ -131,7 +126,7 @@ where
         let file_id = crate_graph.crate_root(self.def_map.krate);
         let raw_items = self.db.raw_items(file_id.into());
         let module_id = self.def_map.root;
-        self.def_map.modules[module_id].definition = Some(file_id);
+        self.def_map.modules[module_id].origin = ModuleOrigin::CrateRoot { definition: file_id };
         ModCollector {
             def_collector: &mut *self,
             module_id,
@@ -145,9 +140,11 @@ where
         let mut i = 0;
         loop {
             self.db.check_canceled();
-            match (self.resolve_imports(), self.resolve_macros()) {
-                (ReachedFixedPoint::Yes, ReachedFixedPoint::Yes) => break,
-                _ => i += 1,
+            self.resolve_imports();
+
+            match self.resolve_macros() {
+                ReachedFixedPoint::Yes => break,
+                ReachedFixedPoint::No => i += 1,
             }
             if i == 1000 {
                 log::error!("name resolution is stuck");
@@ -155,10 +152,26 @@ where
             }
         }
 
+        // Resolve all indeterminate resolved imports again
+        // As some of the macros will expand newly import shadowing partial resolved imports
+        // FIXME: We maybe could skip this, if we handle the Indetermine imports in `resolve_imports`
+        // correctly
+        let partial_resolved = self.resolved_imports.iter().filter_map(|directive| {
+            if let PartialResolvedImport::Indeterminate(_) = directive.status {
+                let mut directive = directive.clone();
+                directive.status = PartialResolvedImport::Unresolved;
+                Some(directive)
+            } else {
+                None
+            }
+        });
+        self.unresolved_imports.extend(partial_resolved);
+        self.resolve_imports();
+
         let unresolved_imports = std::mem::replace(&mut self.unresolved_imports, Vec::new());
         // show unresolved imports in completion, etc
-        for (module_id, import, import_data) in unresolved_imports {
-            self.record_resolved_import(module_id, PerNs::none(), import, &import_data)
+        for directive in unresolved_imports {
+            self.record_resolved_import(&directive)
         }
     }
 
@@ -201,24 +214,20 @@ where
         // In Rust, `#[macro_export]` macros are unconditionally visible at the
         // crate root, even if the parent modules is **not** visible.
         if export {
-            self.update(
-                self.def_map.root,
-                None,
-                &[(name, Resolution { def: PerNs::macros(macro_), import: None })],
-            );
+            self.update(self.def_map.root, &[(name, PerNs::macros(macro_))]);
         }
     }
 
     /// Define a legacy textual scoped macro in module
     ///
-    /// We use a map `legacy_macros` to store all legacy textual scoped macros visable per module.
+    /// We use a map `legacy_macros` to store all legacy textual scoped macros visible per module.
     /// It will clone all macros from parent legacy scope, whose definition is prior to
     /// the definition of current module.
-    /// And also, `macro_use` on a module will import all legacy macros visable inside to
+    /// And also, `macro_use` on a module will import all legacy macros visible inside to
     /// current legacy scope, with possible shadowing.
-    fn define_legacy_macro(&mut self, module_id: LocalModuleId, name: Name, macro_: MacroDefId) {
+    fn define_legacy_macro(&mut self, module_id: LocalModuleId, name: Name, mac: MacroDefId) {
         // Always shadowing
-        self.def_map.modules[module_id].scope.legacy_macros.insert(name, macro_);
+        self.def_map.modules[module_id].scope.define_legacy_macro(name, mac);
     }
 
     /// Import macros from `#[macro_use] extern crate`.
@@ -259,31 +268,43 @@ where
         }
     }
 
-    fn resolve_imports(&mut self) -> ReachedFixedPoint {
-        let mut imports = std::mem::replace(&mut self.unresolved_imports, Vec::new());
-        let mut resolved = Vec::new();
-        imports.retain(|(module_id, import, import_data)| {
-            let (def, fp) = self.resolve_import(*module_id, import_data);
-            if fp == ReachedFixedPoint::Yes {
-                resolved.push((*module_id, def, *import, import_data.clone()))
+    /// Import resolution
+    ///
+    /// This is a fix point algorithm. We resolve imports until no forward
+    /// progress in resolving imports is made
+    fn resolve_imports(&mut self) {
+        let mut n_previous_unresolved = self.unresolved_imports.len() + 1;
+
+        while self.unresolved_imports.len() < n_previous_unresolved {
+            n_previous_unresolved = self.unresolved_imports.len();
+            let imports = std::mem::replace(&mut self.unresolved_imports, Vec::new());
+            for mut directive in imports {
+                directive.status = self.resolve_import(directive.module_id, &directive.import);
+
+                match directive.status {
+                    PartialResolvedImport::Indeterminate(_) => {
+                        self.record_resolved_import(&directive);
+                        // FIXME: For avoid performance regression,
+                        // we consider an imported resolved if it is indeterminate (i.e not all namespace resolved)
+                        self.resolved_imports.push(directive)
+                    }
+                    PartialResolvedImport::Resolved(_) => {
+                        self.record_resolved_import(&directive);
+                        self.resolved_imports.push(directive)
+                    }
+                    PartialResolvedImport::Unresolved => {
+                        self.unresolved_imports.push(directive);
+                    }
+                }
             }
-            fp == ReachedFixedPoint::No
-        });
-        self.unresolved_imports = imports;
-        // Resolves imports, filling-in module scopes
-        let result =
-            if resolved.is_empty() { ReachedFixedPoint::Yes } else { ReachedFixedPoint::No };
-        for (module_id, def, import, import_data) in resolved {
-            self.record_resolved_import(module_id, def, import, &import_data)
         }
-        result
     }
 
     fn resolve_import(
         &self,
         module_id: LocalModuleId,
         import: &raw::ImportData,
-    ) -> (PerNs, ReachedFixedPoint) {
+    ) -> PartialResolvedImport {
         log::debug!("resolving import: {:?} ({:?})", import, self.def_map.edition);
         if import.is_extern_crate {
             let res = self.def_map.resolve_name_in_extern_prelude(
@@ -292,26 +313,45 @@ where
                     .as_ident()
                     .expect("extern crate should have been desugared to one-element path"),
             );
-            (res, ReachedFixedPoint::Yes)
+            PartialResolvedImport::Resolved(res)
         } else {
             let res = self.def_map.resolve_path_fp_with_macro(
                 self.db,
                 ResolveMode::Import,
                 module_id,
                 &import.path,
+                BuiltinShadowMode::Module,
             );
 
-            (res.resolved_def, res.reached_fixedpoint)
+            let def = res.resolved_def;
+            if res.reached_fixedpoint == ReachedFixedPoint::No {
+                return PartialResolvedImport::Unresolved;
+            }
+
+            if let Some(krate) = res.krate {
+                if krate != self.def_map.krate {
+                    return PartialResolvedImport::Resolved(def);
+                }
+            }
+
+            // Check whether all namespace is resolved
+            if def.take_types().is_some()
+                && def.take_values().is_some()
+                && def.take_macros().is_some()
+            {
+                PartialResolvedImport::Resolved(def)
+            } else {
+                PartialResolvedImport::Indeterminate(def)
+            }
         }
     }
 
-    fn record_resolved_import(
-        &mut self,
-        module_id: LocalModuleId,
-        def: PerNs,
-        import_id: LocalImportId,
-        import: &raw::ImportData,
-    ) {
+    fn record_resolved_import(&mut self, directive: &ImportDirective) {
+        let module_id = directive.module_id;
+        let import_id = directive.import_id;
+        let import = &directive.import;
+        let def = directive.status.namespaces();
+
         if import.is_glob {
             log::debug!("glob import: {:?}", import);
             match def.take_types() {
@@ -326,13 +366,9 @@ where
                         let scope = &item_map[m.local_id].scope;
 
                         // Module scoped macros is included
-                        let items = scope
-                            .items
-                            .iter()
-                            .map(|(name, res)| (name.clone(), res.clone()))
-                            .collect::<Vec<_>>();
+                        let items = scope.collect_resolutions();
 
-                        self.update(module_id, Some(import_id), &items);
+                        self.update(module_id, &items);
                     } else {
                         // glob import from same crate => we do an initial
                         // import, and then need to propagate any further
@@ -340,18 +376,14 @@ where
                         let scope = &self.def_map[m.local_id].scope;
 
                         // Module scoped macros is included
-                        let items = scope
-                            .items
-                            .iter()
-                            .map(|(name, res)| (name.clone(), res.clone()))
-                            .collect::<Vec<_>>();
+                        let items = scope.collect_resolutions();
 
-                        self.update(module_id, Some(import_id), &items);
+                        self.update(module_id, &items);
                         // record the glob import in case we add further items
-                        self.glob_imports
-                            .entry(m.local_id)
-                            .or_default()
-                            .push((module_id, import_id));
+                        let glob = self.glob_imports.entry(m.local_id).or_default();
+                        if !glob.iter().any(|it| *it == (module_id, import_id)) {
+                            glob.push((module_id, import_id));
+                        }
                     }
                 }
                 Some(ModuleDefId::AdtId(AdtId::EnumId(e))) => {
@@ -361,17 +393,14 @@ where
                     let resolutions = enum_data
                         .variants
                         .iter()
-                        .filter_map(|(local_id, variant_data)| {
+                        .map(|(local_id, variant_data)| {
                             let name = variant_data.name.clone();
                             let variant = EnumVariantId { parent: e, local_id };
-                            let res = Resolution {
-                                def: PerNs::both(variant.into(), variant.into()),
-                                import: Some(import_id),
-                            };
-                            Some((name, res))
+                            let res = PerNs::both(variant.into(), variant.into());
+                            (name, res)
                         })
                         .collect::<Vec<_>>();
-                    self.update(module_id, Some(import_id), &resolutions);
+                    self.update(module_id, &resolutions);
                 }
                 Some(d) => {
                     log::debug!("glob import {:?} from non-module/enum {:?}", import, d);
@@ -383,7 +412,7 @@ where
         } else {
             match import.path.segments.last() {
                 Some(last_segment) => {
-                    let name = import.alias.clone().unwrap_or_else(|| last_segment.name.clone());
+                    let name = import.alias.clone().unwrap_or_else(|| last_segment.clone());
                     log::debug!("resolved import {:?} ({:?}) to {:?}", name, import, def);
 
                     // extern crates in the crate root are special-cased to insert entries into the extern prelude: rust-lang/rust#54658
@@ -393,62 +422,31 @@ where
                         }
                     }
 
-                    let resolution = Resolution { def, import: Some(import_id) };
-                    self.update(module_id, Some(import_id), &[(name, resolution)]);
+                    self.update(module_id, &[(name, def)]);
                 }
                 None => tested_by!(bogus_paths),
             }
         }
     }
 
-    fn update(
-        &mut self,
-        module_id: LocalModuleId,
-        import: Option<LocalImportId>,
-        resolutions: &[(Name, Resolution)],
-    ) {
-        self.update_recursive(module_id, import, resolutions, 0)
+    fn update(&mut self, module_id: LocalModuleId, resolutions: &[(Name, PerNs)]) {
+        self.update_recursive(module_id, resolutions, 0)
     }
 
     fn update_recursive(
         &mut self,
         module_id: LocalModuleId,
-        import: Option<LocalImportId>,
-        resolutions: &[(Name, Resolution)],
+        resolutions: &[(Name, PerNs)],
         depth: usize,
     ) {
         if depth > 100 {
             // prevent stack overflows (but this shouldn't be possible)
             panic!("infinite recursion in glob imports!");
         }
-        let module_items = &mut self.def_map.modules[module_id].scope;
+        let scope = &mut self.def_map.modules[module_id].scope;
         let mut changed = false;
         for (name, res) in resolutions {
-            let existing = module_items.items.entry(name.clone()).or_default();
-
-            if existing.def.types.is_none() && res.def.types.is_some() {
-                existing.def.types = res.def.types;
-                existing.import = import.or(res.import);
-                changed = true;
-            }
-            if existing.def.values.is_none() && res.def.values.is_some() {
-                existing.def.values = res.def.values;
-                existing.import = import.or(res.import);
-                changed = true;
-            }
-            if existing.def.macros.is_none() && res.def.macros.is_some() {
-                existing.def.macros = res.def.macros;
-                existing.import = import.or(res.import);
-                changed = true;
-            }
-
-            if existing.def.is_none()
-                && res.def.is_none()
-                && existing.import.is_none()
-                && res.import.is_some()
-            {
-                existing.import = res.import;
-            }
+            changed |= scope.push_res(name.clone(), *res);
         }
 
         if !changed {
@@ -461,27 +459,48 @@ where
             .flat_map(|v| v.iter())
             .cloned()
             .collect::<Vec<_>>();
-        for (glob_importing_module, glob_import) in glob_imports {
+        for (glob_importing_module, _glob_import) in glob_imports {
             // We pass the glob import so that the tracked import in those modules is that glob import
-            self.update_recursive(glob_importing_module, Some(glob_import), resolutions, depth + 1);
+            self.update_recursive(glob_importing_module, resolutions, depth + 1);
         }
     }
 
     fn resolve_macros(&mut self) -> ReachedFixedPoint {
         let mut macros = std::mem::replace(&mut self.unexpanded_macros, Vec::new());
+        let mut attribute_macros =
+            std::mem::replace(&mut self.unexpanded_attribute_macros, Vec::new());
         let mut resolved = Vec::new();
         let mut res = ReachedFixedPoint::Yes;
-        macros.retain(|(module_id, ast_id, path)| {
+        macros.retain(|directive| {
+            if let Some(call_id) = directive.legacy {
+                res = ReachedFixedPoint::No;
+                resolved.push((directive.module_id, call_id));
+                return false;
+            }
+
             let resolved_res = self.def_map.resolve_path_fp_with_macro(
                 self.db,
                 ResolveMode::Other,
-                *module_id,
-                path,
+                directive.module_id,
+                &directive.path,
+                BuiltinShadowMode::Module,
             );
 
             if let Some(def) = resolved_res.resolved_def.take_macros() {
-                let call_id = def.as_call_id(self.db, *ast_id);
-                resolved.push((*module_id, call_id, def));
+                let call_id = def.as_call_id(self.db, MacroCallKind::FnLike(directive.ast_id));
+                resolved.push((directive.module_id, call_id));
+                res = ReachedFixedPoint::No;
+                return false;
+            }
+
+            true
+        });
+        attribute_macros.retain(|(module_id, ast_id, path)| {
+            let resolved_res = self.resolve_attribute_macro(path);
+
+            if let Some(def) = resolved_res {
+                let call_id = def.as_call_id(self.db, MacroCallKind::Attr(*ast_id));
+                resolved.push((*module_id, call_id));
                 res = ReachedFixedPoint::No;
                 return false;
             }
@@ -490,44 +509,41 @@ where
         });
 
         self.unexpanded_macros = macros;
+        self.unexpanded_attribute_macros = attribute_macros;
 
-        for (module_id, macro_call_id, macro_def_id) in resolved {
-            self.collect_macro_expansion(module_id, macro_call_id, macro_def_id);
+        for (module_id, macro_call_id) in resolved {
+            self.collect_macro_expansion(module_id, macro_call_id);
         }
 
         res
     }
 
-    fn collect_macro_expansion(
-        &mut self,
-        module_id: LocalModuleId,
-        macro_call_id: MacroCallId,
-        macro_def_id: MacroDefId,
-    ) {
-        if self.poison_macros.contains(&macro_def_id) {
-            return;
-        }
-
-        self.macro_stack_monitor.increase(macro_def_id);
-
-        if !self.macro_stack_monitor.is_poison(macro_def_id) {
-            let file_id: HirFileId = macro_call_id.as_file(MacroFileKind::Items);
-            let raw_items = self.db.raw_items(file_id);
-            let mod_dir = self.mod_dirs[&module_id].clone();
-            ModCollector {
-                def_collector: &mut *self,
-                file_id,
-                module_id,
-                raw_items: &raw_items,
-                mod_dir,
+    fn resolve_attribute_macro(&self, path: &ModPath) -> Option<MacroDefId> {
+        // FIXME this is currently super hacky, just enough to support the
+        // built-in derives
+        if let Some(name) = path.as_ident() {
+            // FIXME this should actually be handled with the normal name
+            // resolution; the std lib defines built-in stubs for the derives,
+            // but these are new-style `macro`s, which we don't support yet
+            if let Some(def_id) = find_builtin_derive(name) {
+                return Some(def_id);
             }
-            .collect(raw_items.items());
-        } else {
-            log::error!("Too deep macro expansion: {:?}", macro_call_id);
-            self.poison_macros.insert(macro_def_id);
         }
+        None
+    }
 
-        self.macro_stack_monitor.decrease(macro_def_id);
+    fn collect_macro_expansion(&mut self, module_id: LocalModuleId, macro_call_id: MacroCallId) {
+        let file_id: HirFileId = macro_call_id.as_file();
+        let raw_items = self.db.raw_items(file_id);
+        let mod_dir = self.mod_dirs[&module_id].clone();
+        ModCollector {
+            def_collector: &mut *self,
+            file_id,
+            module_id,
+            raw_items: &raw_items,
+            mod_dir,
+        }
+        .collect(raw_items.items());
     }
 
     fn finish(self) -> CrateDefMap {
@@ -581,20 +597,31 @@ where
                     raw::RawItemKind::Module(m) => {
                         self.collect_module(&self.raw_items[m], &item.attrs)
                     }
-                    raw::RawItemKind::Import(import_id) => self
-                        .def_collector
-                        .unresolved_imports
-                        .push((self.module_id, import_id, self.raw_items[import_id].clone())),
-                    raw::RawItemKind::Def(def) => self.define_def(&self.raw_items[def]),
+                    raw::RawItemKind::Import(import_id) => {
+                        self.def_collector.unresolved_imports.push(ImportDirective {
+                            module_id: self.module_id,
+                            import_id,
+                            import: self.raw_items[import_id].clone(),
+                            status: PartialResolvedImport::Unresolved,
+                        })
+                    }
+                    raw::RawItemKind::Def(def) => {
+                        self.define_def(&self.raw_items[def], &item.attrs)
+                    }
                     raw::RawItemKind::Macro(mac) => self.collect_macro(&self.raw_items[mac]),
                     raw::RawItemKind::Impl(imp) => {
                         let module = ModuleId {
                             krate: self.def_collector.def_map.krate,
                             local_id: self.module_id,
                         };
-                        let ctx = LocationCtx::new(self.def_collector.db, module, self.file_id);
-                        let imp_id = ImplId::from_ast_id(ctx, self.raw_items[imp].ast_id);
-                        self.def_collector.def_map.modules[self.module_id].impls.push(imp_id)
+                        let container = ContainerId::ModuleId(module);
+                        let ast_id = self.raw_items[imp].ast_id;
+                        let impl_id =
+                            ImplLoc { container, ast_id: AstId::new(self.file_id, ast_id) }
+                                .intern(self.def_collector.db);
+                        self.def_collector.def_map.modules[self.module_id]
+                            .scope
+                            .define_impl(impl_id)
                     }
                 }
             }
@@ -667,72 +694,91 @@ where
         let modules = &mut self.def_collector.def_map.modules;
         let res = modules.alloc(ModuleData::default());
         modules[res].parent = Some(self.module_id);
-        modules[res].declaration = Some(declaration);
-        modules[res].definition = definition;
-        modules[res].scope.legacy_macros = modules[self.module_id].scope.legacy_macros.clone();
+        modules[res].origin = ModuleOrigin::not_sure_file(definition, declaration);
+        for (name, mac) in modules[self.module_id].scope.collect_legacy_macros() {
+            modules[res].scope.define_legacy_macro(name, mac)
+        }
         modules[self.module_id].children.insert(name.clone(), res);
-        let resolution = Resolution {
-            def: PerNs::types(
-                ModuleId { krate: self.def_collector.def_map.krate, local_id: res }.into(),
-            ),
-            import: None,
-        };
-        self.def_collector.update(self.module_id, None, &[(name, resolution)]);
+        let module = ModuleId { krate: self.def_collector.def_map.krate, local_id: res };
+        let def: ModuleDefId = module.into();
+        self.def_collector.def_map.modules[self.module_id].scope.define_def(def);
+        self.def_collector.update(self.module_id, &[(name, def.into())]);
         res
     }
 
-    fn define_def(&mut self, def: &raw::DefData) {
+    fn define_def(&mut self, def: &raw::DefData, attrs: &Attrs) {
         let module = ModuleId { krate: self.def_collector.def_map.krate, local_id: self.module_id };
-        let ctx = LocationCtx::new(self.def_collector.db, module, self.file_id);
+        // FIXME: check attrs to see if this is an attribute macro invocation;
+        // in which case we don't add the invocation, just a single attribute
+        // macro invocation
 
-        let name = def.name.clone();
-        let def: PerNs = match def.kind {
-            raw::DefKind::Function(ast_id) => {
-                let def = FunctionLoc {
-                    container: ContainerId::ModuleId(module),
-                    ast_id: AstId::new(self.file_id, ast_id),
-                }
-                .intern(self.def_collector.db);
+        self.collect_derives(attrs, def);
 
-                PerNs::values(def.into())
+        let name = def.name.clone();
+        let container = ContainerId::ModuleId(module);
+        let def: ModuleDefId = match def.kind {
+            raw::DefKind::Function(ast_id) => FunctionLoc {
+                container: container.into(),
+                ast_id: AstId::new(self.file_id, ast_id),
             }
+            .intern(self.def_collector.db)
+            .into(),
             raw::DefKind::Struct(ast_id) => {
-                let id = StructId::from_ast_id(ctx, ast_id).into();
-                PerNs::both(id, id)
+                StructLoc { container, ast_id: AstId::new(self.file_id, ast_id) }
+                    .intern(self.def_collector.db)
+                    .into()
             }
             raw::DefKind::Union(ast_id) => {
-                let id = UnionId::from_ast_id(ctx, ast_id).into();
-                PerNs::both(id, id)
+                UnionLoc { container, ast_id: AstId::new(self.file_id, ast_id) }
+                    .intern(self.def_collector.db)
+                    .into()
+            }
+            raw::DefKind::Enum(ast_id) => {
+                EnumLoc { container, ast_id: AstId::new(self.file_id, ast_id) }
+                    .intern(self.def_collector.db)
+                    .into()
             }
-            raw::DefKind::Enum(ast_id) => PerNs::types(EnumId::from_ast_id(ctx, ast_id).into()),
             raw::DefKind::Const(ast_id) => {
-                let def = ConstLoc {
-                    container: ContainerId::ModuleId(module),
-                    ast_id: AstId::new(self.file_id, ast_id),
-                }
-                .intern(self.def_collector.db);
-
-                PerNs::values(def.into())
+                ConstLoc { container: container.into(), ast_id: AstId::new(self.file_id, ast_id) }
+                    .intern(self.def_collector.db)
+                    .into()
             }
             raw::DefKind::Static(ast_id) => {
-                let def = StaticLoc { container: module, ast_id: AstId::new(self.file_id, ast_id) }
-                    .intern(self.def_collector.db);
-
-                PerNs::values(def.into())
+                StaticLoc { container, ast_id: AstId::new(self.file_id, ast_id) }
+                    .intern(self.def_collector.db)
+                    .into()
             }
-            raw::DefKind::Trait(ast_id) => PerNs::types(TraitId::from_ast_id(ctx, ast_id).into()),
-            raw::DefKind::TypeAlias(ast_id) => {
-                let def = TypeAliasLoc {
-                    container: ContainerId::ModuleId(module),
-                    ast_id: AstId::new(self.file_id, ast_id),
-                }
-                .intern(self.def_collector.db);
-
-                PerNs::types(def.into())
+            raw::DefKind::Trait(ast_id) => {
+                TraitLoc { container, ast_id: AstId::new(self.file_id, ast_id) }
+                    .intern(self.def_collector.db)
+                    .into()
             }
+            raw::DefKind::TypeAlias(ast_id) => TypeAliasLoc {
+                container: container.into(),
+                ast_id: AstId::new(self.file_id, ast_id),
+            }
+            .intern(self.def_collector.db)
+            .into(),
         };
-        let resolution = Resolution { def, import: None };
-        self.def_collector.update(self.module_id, None, &[(name, resolution)])
+        self.def_collector.def_map.modules[self.module_id].scope.define_def(def);
+        self.def_collector.update(self.module_id, &[(name, def.into())])
+    }
+
+    fn collect_derives(&mut self, attrs: &Attrs, def: &raw::DefData) {
+        for derive_subtree in attrs.by_key("derive").tt_values() {
+            // for #[derive(Copy, Clone)], `derive_subtree` is the `(Copy, Clone)` subtree
+            for tt in &derive_subtree.token_trees {
+                let ident = match &tt {
+                    tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => ident,
+                    tt::TokenTree::Leaf(tt::Leaf::Punct(_)) => continue, // , is ok
+                    _ => continue, // anything else would be an error (which we currently ignore)
+                };
+                let path = ModPath::from_tt_ident(ident);
+
+                let ast_id = AstId::new(self.file_id, def.kind.ast_id());
+                self.def_collector.unexpanded_attribute_macros.push((self.module_id, ast_id, path));
+            }
+        }
     }
 
     fn collect_macro(&mut self, mac: &raw::MacroData) {
@@ -758,8 +804,8 @@ where
         if is_macro_rules(&mac.path) {
             if let Some(name) = &mac.name {
                 let macro_id = MacroDefId {
-                    ast_id,
-                    krate: self.def_collector.def_map.krate,
+                    ast_id: Some(ast_id),
+                    krate: Some(self.def_collector.def_map.krate),
                     kind: MacroDefKind::Declarative,
                 };
                 self.def_collector.define_macro(self.module_id, name.clone(), macro_id, mac.export);
@@ -767,14 +813,20 @@ where
             return;
         }
 
-        // Case 2: try to resolve in legacy scope and expand macro_rules, triggering
-        // recursive item collection.
+        // Case 2: try to resolve in legacy scope and expand macro_rules
         if let Some(macro_def) = mac.path.as_ident().and_then(|name| {
             self.def_collector.def_map[self.module_id].scope.get_legacy_macro(&name)
         }) {
-            let macro_call_id = macro_def.as_call_id(self.def_collector.db, ast_id);
+            let macro_call_id =
+                macro_def.as_call_id(self.def_collector.db, MacroCallKind::FnLike(ast_id));
+
+            self.def_collector.unexpanded_macros.push(MacroDirective {
+                module_id: self.module_id,
+                path: mac.path.clone(),
+                ast_id,
+                legacy: Some(macro_call_id),
+            });
 
-            self.def_collector.collect_macro_expansion(self.module_id, macro_call_id, macro_def);
             return;
         }
 
@@ -782,13 +834,19 @@ where
         // We rewrite simple path `macro_name` to `self::macro_name` to force resolve in module scope only.
         let mut path = mac.path.clone();
         if path.is_ident() {
-            path.kind = PathKind::Self_;
+            path.kind = PathKind::Super(0);
         }
-        self.def_collector.unexpanded_macros.push((self.module_id, ast_id, path));
+
+        self.def_collector.unexpanded_macros.push(MacroDirective {
+            module_id: self.module_id,
+            path,
+            ast_id,
+            legacy: None,
+        });
     }
 
     fn import_all_legacy_macros(&mut self, module_id: LocalModuleId) {
-        let macros = self.def_collector.def_map[module_id].scope.legacy_macros.clone();
+        let macros = self.def_collector.def_map[module_id].scope.collect_legacy_macros();
         for (name, macro_) in macros {
             self.def_collector.define_legacy_macro(self.module_id, name.clone(), macro_);
         }
@@ -803,45 +861,35 @@ where
     }
 }
 
-fn is_macro_rules(path: &Path) -> bool {
-    path.as_ident() == Some(&name::MACRO_RULES)
+fn is_macro_rules(path: &ModPath) -> bool {
+    path.as_ident() == Some(&name![macro_rules])
 }
 
 #[cfg(test)]
 mod tests {
+    use crate::{db::DefDatabase, test_db::TestDB};
     use ra_arena::Arena;
     use ra_db::{fixture::WithFixture, SourceDatabase};
-    use rustc_hash::FxHashSet;
-
-    use crate::{db::DefDatabase, test_db::TestDB};
 
     use super::*;
 
-    fn do_collect_defs(
-        db: &impl DefDatabase,
-        def_map: CrateDefMap,
-        monitor: MacroStackMonitor,
-    ) -> (CrateDefMap, FxHashSet<MacroDefId>) {
+    fn do_collect_defs(db: &impl DefDatabase, def_map: CrateDefMap) -> CrateDefMap {
         let mut collector = DefCollector {
             db,
             def_map,
             glob_imports: FxHashMap::default(),
             unresolved_imports: Vec::new(),
+            resolved_imports: Vec::new(),
             unexpanded_macros: Vec::new(),
+            unexpanded_attribute_macros: Vec::new(),
             mod_dirs: FxHashMap::default(),
-            macro_stack_monitor: monitor,
-            poison_macros: FxHashSet::default(),
             cfg_options: &CfgOptions::default(),
         };
         collector.collect();
-        (collector.def_map, collector.poison_macros)
+        collector.def_map
     }
 
-    fn do_limited_resolve(
-        code: &str,
-        limit: u32,
-        poison_limit: u32,
-    ) -> (CrateDefMap, FxHashSet<MacroDefId>) {
+    fn do_resolve(code: &str) -> CrateDefMap {
         let (db, _file_id) = TestDB::with_single_file(&code);
         let krate = db.test_crate();
 
@@ -859,59 +907,18 @@ mod tests {
                 diagnostics: Vec::new(),
             }
         };
-
-        let mut monitor = MacroStackMonitor::default();
-        monitor.validator = Some(Box::new(move |count| {
-            assert!(count < limit);
-            count >= poison_limit
-        }));
-
-        do_collect_defs(&db, def_map, monitor)
+        do_collect_defs(&db, def_map)
     }
 
     #[test]
-    fn test_macro_expand_limit_width() {
-        do_limited_resolve(
+    fn test_macro_expand_will_stop() {
+        do_resolve(
             r#"
         macro_rules! foo {
             ($($ty:ty)*) => { foo!($($ty)*, $($ty)*); }
         }
 foo!(KABOOM);
         "#,
-            16,
-            1000,
         );
     }
-
-    #[test]
-    fn test_macro_expand_poisoned() {
-        let (_, poison_macros) = do_limited_resolve(
-            r#"
-        macro_rules! foo {
-            ($ty:ty) => { foo!($ty); }
-        }
-foo!(KABOOM);
-        "#,
-            100,
-            16,
-        );
-
-        assert_eq!(poison_macros.len(), 1);
-    }
-
-    #[test]
-    fn test_macro_expand_normal() {
-        let (_, poison_macros) = do_limited_resolve(
-            r#"
-        macro_rules! foo {
-            ($ident:ident) => { struct $ident {} }
-        }
-foo!(Bar);
-        "#,
-            16,
-            16,
-        );
-
-        assert_eq!(poison_macros.len(), 0);
-    }
 }