7 files changed, 105 insertions, 22 deletions

diff --git a/crates/ra_hir_def/src/body.rs b/crates/ra_hir_def/src/body.rs
index 3804b65c7..b69d4dea6 100644
--- a/crates/ra_hir_def/src/body.rs
+++ b/crates/ra_hir_def/src/body.rs
@@ -17,7 +17,7 @@ use crate::{
     expr::{Expr, ExprId, Pat, PatId},
     nameres::CrateDefMap,
     path::Path,
-    AstItemDef, DefWithBodyId, ModuleId,
+    AstItemDef, DefWithBodyId, HasModule, HasSource, Lookup, ModuleId,
 };
 
 pub struct Expander {
@@ -149,6 +149,7 @@ impl Body {
 
         let (file_id, module, body) = match def {
             DefWithBodyId::FunctionId(f) => {
+                let f = f.lookup(db);
                 let src = f.source(db);
                 params = src.value.param_list();
                 (src.file_id, f.module(db), src.value.body().map(ast::Expr::from))
diff --git a/crates/ra_hir_def/src/db.rs b/crates/ra_hir_def/src/db.rs
index fb4402463..e4ffdebe9 100644
--- a/crates/ra_hir_def/src/db.rs
+++ b/crates/ra_hir_def/src/db.rs
@@ -14,13 +14,13 @@ use crate::{
         CrateDefMap,
     },
     traits::{TraitData, TraitItemsIndex},
-    DefWithBodyId, EnumId, ImplId, ItemLoc, ModuleId, StructOrUnionId, TraitId,
+    DefWithBodyId, EnumId, FunctionLoc, ImplId, ItemLoc, ModuleId, StructOrUnionId, TraitId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
 pub trait InternDatabase: SourceDatabase {
     #[salsa::interned]
-    fn intern_function(&self, loc: ItemLoc<ast::FnDef>) -> crate::FunctionId;
+    fn intern_function(&self, loc: FunctionLoc) -> crate::FunctionId;
     #[salsa::interned]
     fn intern_struct_or_union(&self, loc: ItemLoc<ast::StructDef>) -> crate::StructOrUnionId;
     #[salsa::interned]
diff --git a/crates/ra_hir_def/src/generics.rs b/crates/ra_hir_def/src/generics.rs
index 4adfc16bb..11dd2a948 100644
--- a/crates/ra_hir_def/src/generics.rs
+++ b/crates/ra_hir_def/src/generics.rs
@@ -11,7 +11,7 @@ use ra_syntax::ast::{self, NameOwner, TypeBoundsOwner, TypeParamsOwner};
 use crate::{
     db::DefDatabase2,
     type_ref::{TypeBound, TypeRef},
-    AdtId, AstItemDef, GenericDefId,
+    AdtId, AstItemDef, GenericDefId, HasSource, Lookup,
 };
 
 /// Data about a generic parameter (to a function, struct, impl, ...).
@@ -53,7 +53,7 @@ impl GenericParams {
         let start = generics.parent_params.as_ref().map(|p| p.params.len()).unwrap_or(0) as u32;
         // FIXME: add `: Sized` bound for everything except for `Self` in traits
         match def {
-            GenericDefId::FunctionId(it) => generics.fill(&it.source(db).value, start),
+            GenericDefId::FunctionId(it) => generics.fill(&it.lookup(db).source(db).value, start),
             GenericDefId::AdtId(AdtId::StructId(it)) => {
                 generics.fill(&it.0.source(db).value, start)
             }
diff --git a/crates/ra_hir_def/src/impls.rs b/crates/ra_hir_def/src/impls.rs
index 4323dfcb6..9be38c5e1 100644
--- a/crates/ra_hir_def/src/impls.rs
+++ b/crates/ra_hir_def/src/impls.rs
@@ -5,11 +5,12 @@
 
 use std::sync::Arc;
 
+use hir_expand::AstId;
 use ra_syntax::ast;
 
 use crate::{
-    db::DefDatabase2, type_ref::TypeRef, AssocItemId, AstItemDef, ConstId, FunctionId, ImplId,
-    LocationCtx, TypeAliasId,
+    db::DefDatabase2, type_ref::TypeRef, AssocItemId, AstItemDef, ConstId, FunctionContainerId,
+    FunctionLoc, ImplId, Intern, LocationCtx, TypeAliasId,
 };
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -35,7 +36,12 @@ impl ImplData {
                 .impl_items()
                 .map(|item_node| match item_node {
                     ast::ImplItem::FnDef(it) => {
-                        FunctionId::from_ast_id(ctx, items.ast_id(&it)).into()
+                        let func_id = FunctionLoc {
+                            container: FunctionContainerId::ImplId(id),
+                            ast_id: AstId::new(src.file_id, items.ast_id(&it)),
+                        }
+                        .intern(db);
+                        func_id.into()
                     }
                     ast::ImplItem::ConstDef(it) => {
                         ConstId::from_ast_id(ctx, items.ast_id(&it)).into()
diff --git a/crates/ra_hir_def/src/lib.rs b/crates/ra_hir_def/src/lib.rs
index 38c110570..b9a13776f 100644
--- a/crates/ra_hir_def/src/lib.rs
+++ b/crates/ra_hir_def/src/lib.rs
@@ -199,16 +199,34 @@ pub trait AstItemDef<N: AstNode>: salsa::InternKey + Clone {
 pub struct FunctionId(salsa::InternId);
 impl_intern_key!(FunctionId);
 
-impl AstItemDef<ast::FnDef> for FunctionId {
-    fn intern(db: &impl InternDatabase, loc: ItemLoc<ast::FnDef>) -> Self {
-        db.intern_function(loc)
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct FunctionLoc {
+    pub container: FunctionContainerId,
+    pub ast_id: AstId<ast::FnDef>,
+}
+
+impl Intern for FunctionLoc {
+    type ID = FunctionId;
+    fn intern(self, db: &impl db::DefDatabase2) -> FunctionId {
+        db.intern_function(self)
     }
-    fn lookup_intern(self, db: &impl InternDatabase) -> ItemLoc<ast::FnDef> {
-        db.lookup_intern_function(self)
+}
+
+impl Lookup for FunctionId {
+    type Data = FunctionLoc;
+    fn lookup(&self, db: &impl db::DefDatabase2) -> FunctionLoc {
+        db.lookup_intern_function(*self)
     }
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum FunctionContainerId {
+    ModuleId(ModuleId),
+    ImplId(ImplId),
+    TraitId(TraitId),
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct StructOrUnionId(salsa::InternId);
 impl_intern_key!(StructOrUnionId);
 impl AstItemDef<ast::StructDef> for StructOrUnionId {
@@ -433,3 +451,41 @@ impl_froms!(
     EnumVariantId,
     ConstId
 );
+
+trait Intern {
+    type ID;
+    fn intern(self, db: &impl db::DefDatabase2) -> Self::ID;
+}
+
+pub trait Lookup {
+    type Data;
+    fn lookup(&self, db: &impl db::DefDatabase2) -> Self::Data;
+}
+
+pub trait HasModule {
+    fn module(&self, db: &impl db::DefDatabase2) -> ModuleId;
+}
+
+impl HasModule for FunctionLoc {
+    fn module(&self, db: &impl db::DefDatabase2) -> ModuleId {
+        match self.container {
+            FunctionContainerId::ModuleId(it) => it,
+            FunctionContainerId::ImplId(it) => it.module(db),
+            FunctionContainerId::TraitId(it) => it.module(db),
+        }
+    }
+}
+
+pub trait HasSource {
+    type Value;
+    fn source(&self, db: &impl db::DefDatabase2) -> Source<Self::Value>;
+}
+
+impl HasSource for FunctionLoc {
+    type Value = ast::FnDef;
+
+    fn source(&self, db: &impl db::DefDatabase2) -> Source<ast::FnDef> {
+        let node = self.ast_id.to_node(db);
+        Source::new(self.ast_id.file_id(), node)
+    }
+}
diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index 8f426b097..d2ed94a87 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -19,9 +19,9 @@ use crate::{
         per_ns::PerNs, raw, CrateDefMap, ModuleData, Resolution, ResolveMode,
     },
     path::{Path, PathKind},
-    AdtId, AstId, AstItemDef, ConstId, CrateModuleId, EnumId, EnumVariantId, FunctionId, ImplId,
-    LocationCtx, ModuleDefId, ModuleId, StaticId, StructId, StructOrUnionId, TraitId, TypeAliasId,
-    UnionId,
+    AdtId, AstId, AstItemDef, ConstId, CrateModuleId, EnumId, EnumVariantId, FunctionContainerId,
+    FunctionLoc, ImplId, Intern, LocationCtx, ModuleDefId, ModuleId, StaticId, StructId,
+    StructOrUnionId, TraitId, TypeAliasId, UnionId,
 };
 
 pub(super) fn collect_defs(db: &impl DefDatabase2, mut def_map: CrateDefMap) -> CrateDefMap {
@@ -673,7 +673,12 @@ where
         let name = def.name.clone();
         let def: PerNs = match def.kind {
             raw::DefKind::Function(ast_id) => {
-                let f = FunctionId::from_ast_id(ctx, ast_id);
+                let f = FunctionLoc {
+                    container: FunctionContainerId::ModuleId(module),
+                    ast_id: AstId::new(self.file_id, ast_id),
+                }
+                .intern(self.def_collector.db);
+
                 PerNs::values(f.into())
             }
             raw::DefKind::Struct(ast_id) => {
diff --git a/crates/ra_hir_def/src/traits.rs b/crates/ra_hir_def/src/traits.rs
index a8ba31594..6e36bc0d0 100644
--- a/crates/ra_hir_def/src/traits.rs
+++ b/crates/ra_hir_def/src/traits.rs
@@ -2,14 +2,17 @@
 
 use std::sync::Arc;
 
-use hir_expand::name::{AsName, Name};
+use hir_expand::{
+    name::{AsName, Name},
+    AstId,
+};
 
 use ra_syntax::ast::{self, NameOwner};
 use rustc_hash::FxHashMap;
 
 use crate::{
-    db::DefDatabase2, AssocItemId, AstItemDef, ConstId, FunctionId, LocationCtx, ModuleDefId,
-    ModuleId, TraitId, TypeAliasId,
+    db::DefDatabase2, AssocItemId, AstItemDef, ConstId, FunctionContainerId, FunctionLoc, Intern,
+    LocationCtx, ModuleDefId, ModuleId, TraitId, TypeAliasId,
 };
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -26,11 +29,17 @@ impl TraitData {
         let module = tr.module(db);
         let ctx = LocationCtx::new(db, module, src.file_id);
         let auto = src.value.is_auto();
+        let ast_id_map = db.ast_id_map(src.file_id);
         let items = if let Some(item_list) = src.value.item_list() {
             item_list
                 .impl_items()
                 .map(|item_node| match item_node {
-                    ast::ImplItem::FnDef(it) => FunctionId::from_ast(ctx, &it).into(),
+                    ast::ImplItem::FnDef(it) => FunctionLoc {
+                        container: FunctionContainerId::TraitId(tr),
+                        ast_id: AstId::new(src.file_id, ast_id_map.ast_id(&it)),
+                    }
+                    .intern(db)
+                    .into(),
                     ast::ImplItem::ConstDef(it) => ConstId::from_ast(ctx, &it).into(),
                     ast::ImplItem::TypeAliasDef(it) => TypeAliasId::from_ast(ctx, &it).into(),
                 })
@@ -54,7 +63,13 @@ impl TraitItemsIndex {
         for decl in crate_def_map[module.module_id].scope.declarations() {
             if let ModuleDefId::TraitId(tr) = decl {
                 for item in db.trait_data(tr).items.iter() {
-                    index.traits_by_def.insert(*item, tr);
+                    match item {
+                        AssocItemId::FunctionId(_) => (),
+                        _ => {
+                            let prev = index.traits_by_def.insert(*item, tr);
+                            assert!(prev.is_none());
+                        }
+                    }
                 }
             }
         }