16 files changed, 69 insertions, 32 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 13bbbb74c..af874945c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1123,6 +1123,7 @@ dependencies = [
  "rowan 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-hash 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_lexer 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.103 (registry+https://github.com/rust-lang/crates.io-index)",
  "smol_str 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)",
  "test_utils 0.1.0",
  "walkdir 2.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index c013ff99b..117ca2fe3 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -809,7 +809,10 @@ impl ImplBlock {
         let resolver = self.id.resolver(db);
         let environment = TraitEnvironment::lower(db, &resolver);
         let ty = Ty::from_hir(db, &resolver, &impl_data.target_type);
-        Type { krate: self.id.module(db).krate, ty: InEnvironment { value: ty, environment } }
+        Type {
+            krate: self.id.lookup(db).container.krate,
+            ty: InEnvironment { value: ty, environment },
+        }
     }
 
     pub fn items(&self, db: &impl DefDatabase) -> Vec<AssocItem> {
@@ -821,7 +824,7 @@ impl ImplBlock {
     }
 
     pub fn module(&self, db: &impl DefDatabase) -> Module {
-        self.id.module(db).into()
+        self.id.lookup(db).container.into()
     }
 
     pub fn krate(&self, db: &impl DefDatabase) -> Crate {
diff --git a/crates/ra_hir/src/from_source.rs b/crates/ra_hir/src/from_source.rs
index 307f3d5bf..b35188a21 100644
--- a/crates/ra_hir/src/from_source.rs
+++ b/crates/ra_hir/src/from_source.rs
@@ -107,8 +107,10 @@ impl FromSource for MacroDef {
 impl FromSource for ImplBlock {
     type Ast = ast::ImplBlock;
     fn from_source(db: &(impl DefDatabase + AstDatabase), src: InFile<Self::Ast>) -> Option<Self> {
-        let id = from_source(db, src)?;
-        Some(ImplBlock { id })
+        // XXX: use `.parent()` to avoid finding ourselves
+        let parent = src.value.syntax().parent()?;
+        let container = Container::find(db, src.with_value(parent).as_ref())?;
+        container.child_by_source(db)[keys::IMPL].get(&src).copied().map(ImplBlock::from)
     }
 }
 
diff --git a/crates/ra_hir/src/has_source.rs b/crates/ra_hir/src/has_source.rs
index b09582f93..a888fe995 100644
--- a/crates/ra_hir/src/has_source.rs
+++ b/crates/ra_hir/src/has_source.rs
@@ -114,7 +114,7 @@ impl HasSource for MacroDef {
 impl HasSource for ImplBlock {
     type Ast = ast::ImplBlock;
     fn source(self, db: &impl DefDatabase) -> InFile<ast::ImplBlock> {
-        self.id.source(db)
+        self.id.lookup(db).source(db)
     }
 }
 impl HasSource for Import {
diff --git a/crates/ra_hir_def/src/attr.rs b/crates/ra_hir_def/src/attr.rs
index 2f8f02d82..12d4e777a 100644
--- a/crates/ra_hir_def/src/attr.rs
+++ b/crates/ra_hir_def/src/attr.rs
@@ -64,7 +64,7 @@ impl Attrs {
             AttrDefId::MacroDefId(it) => {
                 it.ast_id.map_or_else(Default::default, |ast_id| attrs_from_ast(ast_id, db))
             }
-            AttrDefId::ImplId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
+            AttrDefId::ImplId(it) => attrs_from_loc(it.lookup(db), db),
             AttrDefId::ConstId(it) => attrs_from_loc(it.lookup(db), db),
             AttrDefId::StaticId(it) => attrs_from_loc(it.lookup(db), db),
             AttrDefId::FunctionId(it) => attrs_from_loc(it.lookup(db), db),
diff --git a/crates/ra_hir_def/src/child_by_source.rs b/crates/ra_hir_def/src/child_by_source.rs
index a3574a9db..821549bd5 100644
--- a/crates/ra_hir_def/src/child_by_source.rs
+++ b/crates/ra_hir_def/src/child_by_source.rs
@@ -98,6 +98,11 @@ impl ChildBySource for ModuleId {
             }
         }
 
+        for &impl_ in crate_def_map[self.local_id].impls.iter() {
+            let src = impl_.lookup(db).source(db);
+            res[keys::IMPL].insert(src, impl_)
+        }
+
         res
     }
 }
diff --git a/crates/ra_hir_def/src/data.rs b/crates/ra_hir_def/src/data.rs
index 095d7064a..42821b9b1 100644
--- a/crates/ra_hir_def/src/data.rs
+++ b/crates/ra_hir_def/src/data.rs
@@ -167,7 +167,7 @@ pub struct ImplData {
 
 impl ImplData {
     pub(crate) fn impl_data_query(db: &impl DefDatabase, id: ImplId) -> Arc<ImplData> {
-        let src = id.source(db);
+        let src = id.lookup(db).source(db);
         let items = db.ast_id_map(src.file_id);
 
         let target_trait = src.value.target_trait().map(TypeRef::from_ast);
diff --git a/crates/ra_hir_def/src/db.rs b/crates/ra_hir_def/src/db.rs
index ef5611ffc..8907aacca 100644
--- a/crates/ra_hir_def/src/db.rs
+++ b/crates/ra_hir_def/src/db.rs
@@ -18,8 +18,8 @@ use crate::{
         CrateDefMap,
     },
     AttrDefId, ConstId, ConstLoc, DefWithBodyId, EnumId, FunctionId, FunctionLoc, GenericDefId,
-    ImplId, ItemLoc, ModuleId, StaticId, StaticLoc, StructId, TraitId, TypeAliasId, TypeAliasLoc,
-    UnionId,
+    ImplId, ImplLoc, ItemLoc, ModuleId, StaticId, StaticLoc, StructId, TraitId, TypeAliasId,
+    TypeAliasLoc, UnionId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
@@ -41,7 +41,7 @@ pub trait InternDatabase: SourceDatabase {
     #[salsa::interned]
     fn intern_type_alias(&self, loc: TypeAliasLoc) -> TypeAliasId;
     #[salsa::interned]
-    fn intern_impl(&self, loc: ItemLoc<ast::ImplBlock>) -> ImplId;
+    fn intern_impl(&self, loc: ImplLoc) -> ImplId;
 }
 
 #[salsa::query_group(DefDatabaseStorage)]
diff --git a/crates/ra_hir_def/src/generics.rs b/crates/ra_hir_def/src/generics.rs
index 976cf72d0..5d1100945 100644
--- a/crates/ra_hir_def/src/generics.rs
+++ b/crates/ra_hir_def/src/generics.rs
@@ -109,7 +109,7 @@ impl GenericParams {
             // type-parameter, but rather is a type-alias for impl's target
             // type, so this is handled by the resolver.
             GenericDefId::ImplId(it) => {
-                let src = it.source(db);
+                let src = it.lookup(db).source(db);
                 generics.fill(&mut sm, &src.value);
                 src.file_id
             }
diff --git a/crates/ra_hir_def/src/keys.rs b/crates/ra_hir_def/src/keys.rs
index be702a4f8..d318b2451 100644
--- a/crates/ra_hir_def/src/keys.rs
+++ b/crates/ra_hir_def/src/keys.rs
@@ -8,7 +8,7 @@ use rustc_hash::FxHashMap;
 
 use crate::{
     dyn_map::{DynMap, Policy},
-    ConstId, EnumVariantId, FunctionId, StaticId, StructFieldId, TypeAliasId, TypeParamId,
+    ConstId, EnumVariantId, FunctionId, ImplId, StaticId, StructFieldId, TypeAliasId, TypeParamId,
 };
 
 type Key<K, V> = crate::dyn_map::Key<InFile<K>, V, AstPtrPolicy<K, V>>;
@@ -16,8 +16,10 @@ type Key<K, V> = crate::dyn_map::Key<InFile<K>, V, AstPtrPolicy<K, V>>;
 pub const FUNCTION: Key<ast::FnDef, FunctionId> = Key::new();
 pub const CONST: Key<ast::ConstDef, ConstId> = Key::new();
 pub const STATIC: Key<ast::StaticDef, StaticId> = Key::new();
-pub const ENUM_VARIANT: Key<ast::EnumVariant, EnumVariantId> = Key::new();
 pub const TYPE_ALIAS: Key<ast::TypeAliasDef, TypeAliasId> = Key::new();
+pub const IMPL: Key<ast::ImplBlock, ImplId> = Key::new();
+
+pub const ENUM_VARIANT: Key<ast::EnumVariant, EnumVariantId> = Key::new();
 pub const TUPLE_FIELD: Key<ast::TupleFieldDef, StructFieldId> = Key::new();
 pub const RECORD_FIELD: Key<ast::RecordFieldDef, StructFieldId> = Key::new();
 pub const TYPE_PARAM: Key<ast::TypeParam, TypeParamId> = Key::new();
diff --git a/crates/ra_hir_def/src/lib.rs b/crates/ra_hir_def/src/lib.rs
index 569da4f28..5564b166b 100644
--- a/crates/ra_hir_def/src/lib.rs
+++ b/crates/ra_hir_def/src/lib.rs
@@ -289,12 +289,24 @@ impl Lookup for TypeAliasId {
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct ImplId(salsa::InternId);
 impl_intern_key!(ImplId);
-impl AstItemDef<ast::ImplBlock> for ImplId {
-    fn intern(db: &impl InternDatabase, loc: ItemLoc<ast::ImplBlock>) -> Self {
-        db.intern_impl(loc)
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ImplLoc {
+    pub container: ModuleId,
+    pub ast_id: AstId<ast::ImplBlock>,
+}
+
+impl Intern for ImplLoc {
+    type ID = ImplId;
+    fn intern(self, db: &impl db::DefDatabase) -> ImplId {
+        db.intern_impl(self)
     }
-    fn lookup_intern(self, db: &impl InternDatabase) -> ItemLoc<ast::ImplBlock> {
-        db.lookup_intern_impl(self)
+}
+
+impl Lookup for ImplId {
+    type Data = ImplLoc;
+    fn lookup(&self, db: &impl db::DefDatabase) -> ImplLoc {
+        db.lookup_intern_impl(*self)
     }
 }
 
@@ -479,7 +491,7 @@ impl HasModule for FunctionLoc {
     fn module(&self, db: &impl db::DefDatabase) -> ModuleId {
         match self.container {
             ContainerId::ModuleId(it) => it,
-            ContainerId::ImplId(it) => it.module(db),
+            ContainerId::ImplId(it) => it.lookup(db).container,
             ContainerId::TraitId(it) => it.module(db),
         }
     }
@@ -489,7 +501,7 @@ impl HasModule for TypeAliasLoc {
     fn module(&self, db: &impl db::DefDatabase) -> ModuleId {
         match self.container {
             ContainerId::ModuleId(it) => it,
-            ContainerId::ImplId(it) => it.module(db),
+            ContainerId::ImplId(it) => it.lookup(db).container,
             ContainerId::TraitId(it) => it.module(db),
         }
     }
@@ -499,7 +511,7 @@ impl HasModule for ConstLoc {
     fn module(&self, db: &impl db::DefDatabase) -> ModuleId {
         match self.container {
             ContainerId::ModuleId(it) => it,
-            ContainerId::ImplId(it) => it.module(db),
+            ContainerId::ImplId(it) => it.lookup(db).container,
             ContainerId::TraitId(it) => it.module(db),
         }
     }
@@ -532,7 +544,7 @@ impl HasModule for GenericDefId {
             GenericDefId::AdtId(it) => it.module(db),
             GenericDefId::TraitId(it) => it.module(db),
             GenericDefId::TypeAliasId(it) => it.lookup(db).module(db),
-            GenericDefId::ImplId(it) => it.module(db),
+            GenericDefId::ImplId(it) => it.lookup(db).container,
             GenericDefId::EnumVariantId(it) => it.parent.module(db),
             GenericDefId::ConstId(it) => it.lookup(db).module(db),
         }
diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index a80067979..b33507a9a 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -24,7 +24,7 @@ use crate::{
     },
     path::{Path, PathKind},
     per_ns::PerNs,
-    AdtId, AstId, AstItemDef, ConstLoc, ContainerId, EnumId, EnumVariantId, FunctionLoc, ImplId,
+    AdtId, AstId, AstItemDef, ConstLoc, ContainerId, EnumId, EnumVariantId, FunctionLoc, ImplLoc,
     Intern, LocalImportId, LocalModuleId, LocationCtx, ModuleDefId, ModuleId, StaticLoc, StructId,
     TraitId, TypeAliasLoc, UnionId,
 };
@@ -661,9 +661,11 @@ where
                             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 ast_id = self.raw_items[imp].ast_id;
+                        let impl_id =
+                            ImplLoc { container: module, ast_id: AstId::new(self.file_id, ast_id) }
+                                .intern(self.def_collector.db);
+                        self.def_collector.def_map.modules[self.module_id].impls.push(impl_id)
                     }
                 }
             }
diff --git a/crates/ra_hir_def/src/resolver.rs b/crates/ra_hir_def/src/resolver.rs
index 9484a61d5..f87b16b44 100644
--- a/crates/ra_hir_def/src/resolver.rs
+++ b/crates/ra_hir_def/src/resolver.rs
@@ -564,7 +564,8 @@ impl HasResolver for TypeAliasId {
 
 impl HasResolver for ImplId {
     fn resolver(self, db: &impl DefDatabase) -> Resolver {
-        self.module(db)
+        self.lookup(db)
+            .container
             .resolver(db)
             .push_generic_params_scope(db, self.into())
             .push_impl_block_scope(self)
diff --git a/crates/ra_hir_def/src/src.rs b/crates/ra_hir_def/src/src.rs
index 27caa02cc..a5c4359a7 100644
--- a/crates/ra_hir_def/src/src.rs
+++ b/crates/ra_hir_def/src/src.rs
@@ -4,7 +4,7 @@ use hir_expand::InFile;
 use ra_arena::map::ArenaMap;
 use ra_syntax::ast;
 
-use crate::{db::DefDatabase, ConstLoc, FunctionLoc, StaticLoc, TypeAliasLoc};
+use crate::{db::DefDatabase, ConstLoc, FunctionLoc, ImplLoc, StaticLoc, TypeAliasLoc};
 
 pub trait HasSource {
     type Value;
@@ -47,6 +47,15 @@ impl HasSource for StaticLoc {
     }
 }
 
+impl HasSource for ImplLoc {
+    type Value = ast::ImplBlock;
+
+    fn source(&self, db: &impl DefDatabase) -> InFile<ast::ImplBlock> {
+        let node = self.ast_id.to_node(db);
+        InFile::new(self.ast_id.file_id, node)
+    }
+}
+
 pub trait HasChildSource {
     type ChildId;
     type Value;
diff --git a/crates/ra_hir_ty/src/method_resolution.rs b/crates/ra_hir_ty/src/method_resolution.rs
index 7220d6e0a..848e306e9 100644
--- a/crates/ra_hir_ty/src/method_resolution.rs
+++ b/crates/ra_hir_ty/src/method_resolution.rs
@@ -6,8 +6,8 @@ use std::sync::Arc;
 
 use arrayvec::ArrayVec;
 use hir_def::{
-    lang_item::LangItemTarget, resolver::Resolver, type_ref::Mutability, AssocItemId, AstItemDef,
-    FunctionId, HasModule, ImplId, Lookup, TraitId,
+    lang_item::LangItemTarget, resolver::Resolver, type_ref::Mutability, AssocItemId, FunctionId,
+    HasModule, ImplId, Lookup, TraitId,
 };
 use hir_expand::name::Name;
 use ra_db::CrateId;
@@ -134,7 +134,7 @@ impl Ty {
                 LangItemTarget::ImplBlockId(it) => Some(it),
                 _ => None,
             })
-            .map(|it| it.module(db).krate)
+            .map(|it| it.lookup(db).container.krate)
             .collect();
         Some(res)
     }
diff --git a/crates/ra_hir_ty/src/traits/chalk.rs b/crates/ra_hir_ty/src/traits/chalk.rs
index 1e7ff93d5..ff299f511 100644
--- a/crates/ra_hir_ty/src/traits/chalk.rs
+++ b/crates/ra_hir_ty/src/traits/chalk.rs
@@ -673,7 +673,7 @@ fn impl_block_datum(
     let bound_vars = Substs::bound_vars(&generic_params);
     let trait_ref = trait_ref.subst(&bound_vars);
     let trait_ = trait_ref.trait_;
-    let impl_type = if impl_id.module(db).krate == krate {
+    let impl_type = if impl_id.lookup(db).container.krate == krate {
         chalk_rust_ir::ImplType::Local
     } else {
         chalk_rust_ir::ImplType::External