3 files changed, 44 insertions, 38 deletions

diff --git a/crates/ra_hir/src/adt.rs b/crates/ra_hir/src/adt.rs
index 6b13b464d..e0f515642 100644
--- a/crates/ra_hir/src/adt.rs
+++ b/crates/ra_hir/src/adt.rs
@@ -3,11 +3,14 @@
 
 use std::sync::Arc;
 
-use ra_syntax::ast::{self, NameOwner, StructFlavor};
+use ra_syntax::{
+    TreeArc,
+    ast::{self, NameOwner, StructFlavor}
+};
 
 use crate::{
     Name, AsName, Struct, Enum, EnumVariant, Crate,
-    HirDatabase,
+    HirDatabase, HirFileId,
     type_ref::TypeRef,
     ids::LocationCtx,
 };
@@ -55,6 +58,24 @@ impl StructData {
     }
 }
 
+fn variants(enum_def: &ast::EnumDef) -> impl Iterator<Item = &ast::EnumVariant> {
+    enum_def
+        .variant_list()
+        .into_iter()
+        .flat_map(|it| it.variants())
+}
+
+impl EnumVariant {
+    pub fn source_impl(&self, db: &impl HirDatabase) -> (HirFileId, TreeArc<ast::EnumVariant>) {
+        let (file_id, enum_def) = self.parent.source(db);
+        let var = variants(&*enum_def)
+            .nth(self.idx as usize)
+            .unwrap()
+            .to_owned();
+        (file_id, var)
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct EnumData {
     pub(crate) name: Option<Name>,
@@ -68,22 +89,19 @@ impl EnumData {
     }
 
     pub(crate) fn enum_data_query(db: &impl HirDatabase, e: Enum) -> Arc<EnumData> {
-        let (file_id, enum_def) = e.source(db);
-        let module = e.module(db);
-        let ctx = LocationCtx::new(db, module, file_id);
-        let variants = if let Some(vl) = enum_def.variant_list() {
-            vl.variants()
-                .filter_map(|variant_def| {
-                    let name = variant_def.name()?.as_name();
-                    let var = EnumVariant {
-                        id: ctx.to_def(variant_def),
-                    };
-                    Some((name, var))
-                })
-                .collect()
-        } else {
-            Vec::new()
-        };
+        let (_file_id, enum_def) = e.source(db);
+        let variants = variants(&*enum_def)
+            .enumerate()
+            .filter_map(|(idx, variant_def)| {
+                let name = variant_def.name()?.as_name();
+                let var = EnumVariant {
+                    parent: e,
+                    idx: idx as u32,
+                };
+                Some((name, var))
+            })
+            .collect();
+
         Arc::new(EnumData::new(&*enum_def, variants))
     }
 }
diff --git a/crates/ra_hir/src/code_model_api.rs b/crates/ra_hir/src/code_model_api.rs
index a469ad477..4fc47aba5 100644
--- a/crates/ra_hir/src/code_model_api.rs
+++ b/crates/ra_hir/src/code_model_api.rs
@@ -15,7 +15,7 @@ use crate::{
     generics::GenericParams,
     docs::{Documentation, Docs, docs_from_ast},
     module_tree::ModuleId,
-    ids::{FunctionId, StructId, EnumId, EnumVariantId, AstItemDef, ConstId, StaticId, TraitId, TypeId},
+    ids::{FunctionId, StructId, EnumId, AstItemDef, ConstId, StaticId, TraitId, TypeId},
 };
 
 /// hir::Crate describes a single crate. It's the main interface with which
@@ -269,18 +269,19 @@ impl Docs for Enum {
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct EnumVariant {
-    pub(crate) id: EnumVariantId,
+    pub(crate) parent: Enum,
+    pub(crate) idx: u32,
 }
 
 impl EnumVariant {
     pub fn source(&self, db: &impl HirDatabase) -> (HirFileId, TreeArc<ast::EnumVariant>) {
-        self.id.source(db)
+        self.source_impl(db)
     }
     pub fn module(&self, db: &impl HirDatabase) -> Module {
-        self.id.module(db)
+        self.parent.module(db)
     }
-    pub fn parent_enum(&self, db: &impl HirDatabase) -> Enum {
-        db.enum_variant_data(*self).parent_enum.clone()
+    pub fn parent_enum(&self, _db: &impl HirDatabase) -> Enum {
+        self.parent
     }
 
     pub fn name(&self, db: &impl HirDatabase) -> Option<Name> {
diff --git a/crates/ra_hir/src/ids.rs b/crates/ra_hir/src/ids.rs
index b125a1518..5272656ec 100644
--- a/crates/ra_hir/src/ids.rs
+++ b/crates/ra_hir/src/ids.rs
@@ -18,7 +18,6 @@ pub struct HirInterner {
     fns: LocationIntener<ItemLoc<ast::FnDef>, FunctionId>,
     structs: LocationIntener<ItemLoc<ast::StructDef>, StructId>,
     enums: LocationIntener<ItemLoc<ast::EnumDef>, EnumId>,
-    enum_variants: LocationIntener<ItemLoc<ast::EnumVariant>, EnumVariantId>,
     consts: LocationIntener<ItemLoc<ast::ConstDef>, ConstId>,
     statics: LocationIntener<ItemLoc<ast::StaticDef>, StaticId>,
     traits: LocationIntener<ItemLoc<ast::TraitDef>, TraitId>,
@@ -31,7 +30,6 @@ impl HirInterner {
             + self.fns.len()
             + self.structs.len()
             + self.enums.len()
-            + self.enum_variants.len()
             + self.consts.len()
             + self.statics.len()
             + self.traits.len()
@@ -262,15 +260,6 @@ impl AstItemDef<ast::EnumDef> for EnumId {
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct EnumVariantId(RawId);
-impl_arena_id!(EnumVariantId);
-impl AstItemDef<ast::EnumVariant> for EnumVariantId {
-    fn interner(interner: &HirInterner) -> &LocationIntener<ItemLoc<ast::EnumVariant>, Self> {
-        &interner.enum_variants
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct ConstId(RawId);
 impl_arena_id!(ConstId);
 impl AstItemDef<ast::ConstDef> for ConstId {
@@ -342,9 +331,7 @@ impl SourceFileItems {
         // change parent's id. This means that, say, adding a new function to a
         // trait does not chage ids of top-level items, which helps caching.
         bfs(source_file.syntax(), |it| {
-            if let Some(enum_variant) = ast::EnumVariant::cast(it) {
-                self.alloc(enum_variant.syntax().to_owned());
-            } else if let Some(module_item) = ast::ModuleItem::cast(it) {
+            if let Some(module_item) = ast::ModuleItem::cast(it) {
                 self.alloc(module_item.syntax().to_owned());
             } else if let Some(macro_call) = ast::MacroCall::cast(it) {
                 self.alloc(macro_call.syntax().to_owned());