1 files changed, 146 insertions, 28 deletions

diff --git a/crates/ra_hir_def/src/item_scope.rs b/crates/ra_hir_def/src/item_scope.rs
index fc15948ad..beeb98559 100644
--- a/crates/ra_hir_def/src/item_scope.rs
+++ b/crates/ra_hir_def/src/item_scope.rs
@@ -1,18 +1,39 @@
 //! Describes items defined or visible (ie, imported) in a certain scope.
 //! This is shared between modules and blocks.
 
+use std::collections::hash_map::Entry;
+
 use hir_expand::name::Name;
 use once_cell::sync::Lazy;
-use rustc_hash::FxHashMap;
+use ra_db::CrateId;
+use rustc_hash::{FxHashMap, FxHashSet};
+use test_utils::mark;
 
 use crate::{
-    per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, ImplId, MacroDefId, ModuleDefId,
-    TraitId,
+    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, HasModule, ImplId,
+    LocalModuleId, Lookup, MacroDefId, ModuleDefId, TraitId,
 };
 
+#[derive(Copy, Clone)]
+pub(crate) enum ImportType {
+    Glob,
+    Named,
+}
+
+#[derive(Debug, Default)]
+pub struct PerNsGlobImports {
+    types: FxHashSet<(LocalModuleId, Name)>,
+    values: FxHashSet<(LocalModuleId, Name)>,
+    macros: FxHashSet<(LocalModuleId, Name)>,
+}
+
 #[derive(Debug, Default, PartialEq, Eq)]
 pub struct ItemScope {
-    visible: FxHashMap<Name, PerNs>,
+    types: FxHashMap<Name, (ModuleDefId, Visibility)>,
+    values: FxHashMap<Name, (ModuleDefId, Visibility)>,
+    macros: FxHashMap<Name, (MacroDefId, Visibility)>,
+    unresolved: FxHashSet<Name>,
+
     defs: Vec<ModuleDefId>,
     impls: Vec<ImplId>,
     /// Macros visible in current module in legacy textual scope
@@ -50,14 +71,16 @@ pub(crate) enum BuiltinShadowMode {
 /// Other methods will only resolve values, types and module scoped macros only.
 impl ItemScope {
     pub fn entries<'a>(&'a self) -> impl Iterator<Item = (&'a Name, PerNs)> + 'a {
-        //FIXME: shadowing
-        self.visible.iter().map(|(n, def)| (n, *def))
-    }
+        // FIXME: shadowing
+        let keys: FxHashSet<_> = self
+            .types
+            .keys()
+            .chain(self.values.keys())
+            .chain(self.macros.keys())
+            .chain(self.unresolved.iter())
+            .collect();
 
-    pub fn entries_without_primitives<'a>(
-        &'a self,
-    ) -> impl Iterator<Item = (&'a Name, PerNs)> + 'a {
-        self.visible.iter().map(|(n, def)| (n, *def))
+        keys.into_iter().map(move |name| (name, self.get(name)))
     }
 
     pub fn declarations(&self) -> impl Iterator<Item = ModuleDefId> + '_ {
@@ -76,7 +99,7 @@ impl ItemScope {
 
     /// Iterate over all module scoped macros
     pub(crate) fn macros<'a>(&'a self) -> impl Iterator<Item = (&'a Name, MacroDefId)> + 'a {
-        self.visible.iter().filter_map(|(name, def)| def.take_macros().map(|macro_| (name, macro_)))
+        self.entries().filter_map(|(name, def)| def.take_macros().map(|macro_| (name, macro_)))
     }
 
     /// Iterate over all legacy textual scoped macros visible at the end of the module
@@ -86,12 +109,16 @@ impl ItemScope {
 
     /// Get a name from current module scope, legacy macros are not included
     pub(crate) fn get(&self, name: &Name) -> PerNs {
-        self.visible.get(name).copied().unwrap_or_else(PerNs::none)
+        PerNs {
+            types: self.types.get(name).copied(),
+            values: self.values.get(name).copied(),
+            macros: self.macros.get(name).copied(),
+        }
     }
 
     pub(crate) fn name_of(&self, item: ItemInNs) -> Option<(&Name, Visibility)> {
-        for (name, per_ns) in &self.visible {
-            if let Some(vis) = item.match_with(*per_ns) {
+        for (name, per_ns) in self.entries() {
+            if let Some(vis) = item.match_with(per_ns) {
                 return Some((name, vis));
             }
         }
@@ -99,8 +126,8 @@ impl ItemScope {
     }
 
     pub(crate) fn traits<'a>(&'a self) -> impl Iterator<Item = TraitId> + 'a {
-        self.visible.values().filter_map(|def| match def.take_types() {
-            Some(ModuleDefId::TraitId(t)) => Some(t),
+        self.types.values().filter_map(|(def, _)| match def {
+            ModuleDefId::TraitId(t) => Some(*t),
             _ => None,
         })
     }
@@ -123,26 +150,99 @@ impl ItemScope {
 
     pub(crate) fn push_res(&mut self, name: Name, def: PerNs) -> bool {
         let mut changed = false;
-        let existing = self.visible.entry(name).or_default();
 
-        if existing.types.is_none() && def.types.is_some() {
-            existing.types = def.types;
-            changed = true;
+        if let Some(types) = def.types {
+            self.types.entry(name.clone()).or_insert_with(|| {
+                changed = true;
+                types
+            });
         }
-        if existing.values.is_none() && def.values.is_some() {
-            existing.values = def.values;
-            changed = true;
+        if let Some(values) = def.values {
+            self.values.entry(name.clone()).or_insert_with(|| {
+                changed = true;
+                values
+            });
+        }
+        if let Some(macros) = def.macros {
+            self.macros.entry(name.clone()).or_insert_with(|| {
+                changed = true;
+                macros
+            });
+        }
+
+        if def.is_none() {
+            if self.unresolved.insert(name) {
+                changed = true;
+            }
+        }
+
+        changed
+    }
+
+    pub(crate) fn push_res_with_import(
+        &mut self,
+        glob_imports: &mut PerNsGlobImports,
+        lookup: (LocalModuleId, Name),
+        def: PerNs,
+        def_import_type: ImportType,
+    ) -> bool {
+        let mut changed = false;
+
+        macro_rules! check_changed {
+            (
+                $changed:ident,
+                ( $this:ident / $def:ident ) . $field:ident,
+                $glob_imports:ident [ $lookup:ident ],
+                $def_import_type:ident
+            ) => {{
+                let existing = $this.$field.entry($lookup.1.clone());
+                match (existing, $def.$field) {
+                    (Entry::Vacant(entry), Some(_)) => {
+                        match $def_import_type {
+                            ImportType::Glob => {
+                                $glob_imports.$field.insert($lookup.clone());
+                            }
+                            ImportType::Named => {
+                                $glob_imports.$field.remove(&$lookup);
+                            }
+                        }
+
+                        if let Some(fld) = $def.$field {
+                            entry.insert(fld);
+                        }
+                        $changed = true;
+                    }
+                    (Entry::Occupied(mut entry), Some(_))
+                        if $glob_imports.$field.contains(&$lookup)
+                            && matches!($def_import_type, ImportType::Named) =>
+                    {
+                        mark::hit!(import_shadowed);
+                        $glob_imports.$field.remove(&$lookup);
+                        if let Some(fld) = $def.$field {
+                            entry.insert(fld);
+                        }
+                        $changed = true;
+                    }
+                    _ => {}
+                }
+            }};
         }
-        if existing.macros.is_none() && def.macros.is_some() {
-            existing.macros = def.macros;
-            changed = true;
+
+        check_changed!(changed, (self / def).types, glob_imports[lookup], def_import_type);
+        check_changed!(changed, (self / def).values, glob_imports[lookup], def_import_type);
+        check_changed!(changed, (self / def).macros, glob_imports[lookup], def_import_type);
+
+        if def.is_none() {
+            if self.unresolved.insert(lookup.1) {
+                changed = true;
+            }
         }
 
         changed
     }
 
     pub(crate) fn resolutions<'a>(&'a self) -> impl Iterator<Item = (Name, PerNs)> + 'a {
-        self.visible.iter().map(|(name, res)| (name.clone(), *res))
+        self.entries().map(|(name, res)| (name.clone(), res))
     }
 
     pub(crate) fn collect_legacy_macros(&self) -> FxHashMap<Name, MacroDefId> {
@@ -203,4 +303,22 @@ impl ItemInNs {
             ItemInNs::Macros(_) => None,
         }
     }
+
+    /// Returns the crate defining this item (or `None` if `self` is built-in).
+    pub fn krate(&self, db: &dyn DefDatabase) -> Option<CrateId> {
+        Some(match self {
+            ItemInNs::Types(did) | ItemInNs::Values(did) => match did {
+                ModuleDefId::ModuleId(id) => id.krate,
+                ModuleDefId::FunctionId(id) => id.lookup(db).module(db).krate,
+                ModuleDefId::AdtId(id) => id.module(db).krate,
+                ModuleDefId::EnumVariantId(id) => id.parent.lookup(db).container.module(db).krate,
+                ModuleDefId::ConstId(id) => id.lookup(db).container.module(db).krate,
+                ModuleDefId::StaticId(id) => id.lookup(db).container.module(db).krate,
+                ModuleDefId::TraitId(id) => id.lookup(db).container.module(db).krate,
+                ModuleDefId::TypeAliasId(id) => id.lookup(db).module(db).krate,
+                ModuleDefId::BuiltinType(_) => return None,
+            },
+            ItemInNs::Macros(id) => return id.krate,
+        })
+    }
 }