27 files changed, 190 insertions, 98 deletions

diff --git a/crates/ra_assists/src/assists/add_new.rs b/crates/ra_assists/src/assists/add_new.rs
index ee8bff346..8f68bd5fb 100644
--- a/crates/ra_assists/src/assists/add_new.rs
+++ b/crates/ra_assists/src/assists/add_new.rs
@@ -35,8 +35,8 @@ pub(crate) fn add_new(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     let strukt = ctx.find_node_at_offset::<ast::StructDef>()?;
 
     // We want to only apply this to non-union structs with named fields
-    let field_list = match (strukt.kind(), strukt.is_union()) {
-        (StructKind::Record(named), false) => named,
+    let field_list = match strukt.kind() {
+        StructKind::Record(named) => named,
         _ => return None,
     };
 
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index 534f1f8e9..ae730beb5 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -320,7 +320,7 @@ pub struct Struct {
 
 impl Struct {
     pub fn module(self, db: &impl DefDatabase) -> Module {
-        Module { id: self.id.0.module(db) }
+        Module { id: self.id.module(db) }
     }
 
     pub fn krate(self, db: &impl DefDatabase) -> Option<Crate> {
@@ -369,11 +369,11 @@ pub struct Union {
 
 impl Union {
     pub fn name(self, db: &impl DefDatabase) -> Option<Name> {
-        db.struct_data(self.id.into()).name.clone()
+        db.union_data(self.id).name.clone()
     }
 
     pub fn module(self, db: &impl DefDatabase) -> Module {
-        Module { id: self.id.0.module(db) }
+        Module { id: self.id.module(db) }
     }
 
     pub fn ty(self, db: &impl HirDatabase) -> Ty {
diff --git a/crates/ra_hir/src/code_model/src.rs b/crates/ra_hir/src/code_model/src.rs
index a4e317c20..076d86f2b 100644
--- a/crates/ra_hir/src/code_model/src.rs
+++ b/crates/ra_hir/src/code_model/src.rs
@@ -51,13 +51,13 @@ impl HasSource for StructField {
 impl HasSource for Struct {
     type Ast = ast::StructDef;
     fn source(self, db: &impl DefDatabase) -> Source<ast::StructDef> {
-        self.id.0.source(db)
+        self.id.source(db)
     }
 }
 impl HasSource for Union {
-    type Ast = ast::StructDef;
-    fn source(self, db: &impl DefDatabase) -> Source<ast::StructDef> {
-        self.id.0.source(db)
+    type Ast = ast::UnionDef;
+    fn source(self, db: &impl DefDatabase) -> Source<ast::UnionDef> {
+        self.id.source(db)
     }
 }
 impl HasSource for Enum {
diff --git a/crates/ra_hir/src/from_source.rs b/crates/ra_hir/src/from_source.rs
index 1e7c22774..95db7161b 100644
--- a/crates/ra_hir/src/from_source.rs
+++ b/crates/ra_hir/src/from_source.rs
@@ -1,6 +1,6 @@
 //! FIXME: write short doc here
 
-use hir_def::{AstItemDef, LocationCtx, ModuleId, StructId, StructOrUnionId, UnionId};
+use hir_def::{AstItemDef, LocationCtx, ModuleId};
 use hir_expand::{name::AsName, AstId, MacroDefId, MacroDefKind};
 use ra_syntax::{
     ast::{self, AstNode, NameOwner},
@@ -19,19 +19,18 @@ pub trait FromSource: Sized {
     fn from_source(db: &(impl DefDatabase + AstDatabase), src: Source<Self::Ast>) -> Option<Self>;
 }
 
-// FIXIME: these two impls are wrong, `ast::StructDef` might produce either a struct or a union
 impl FromSource for Struct {
     type Ast = ast::StructDef;
     fn from_source(db: &(impl DefDatabase + AstDatabase), src: Source<Self::Ast>) -> Option<Self> {
-        let id: StructOrUnionId = from_source(db, src)?;
-        Some(Struct { id: StructId(id) })
+        let id = from_source(db, src)?;
+        Some(Struct { id })
     }
 }
 impl FromSource for Union {
-    type Ast = ast::StructDef;
+    type Ast = ast::UnionDef;
     fn from_source(db: &(impl DefDatabase + AstDatabase), src: Source<Self::Ast>) -> Option<Self> {
-        let id: StructOrUnionId = from_source(db, src)?;
-        Some(Union { id: UnionId(id) })
+        let id = from_source(db, src)?;
+        Some(Union { id })
     }
 }
 impl FromSource for Enum {
diff --git a/crates/ra_hir/src/ty.rs b/crates/ra_hir/src/ty.rs
index 8c045aaef..3cbcbd1d0 100644
--- a/crates/ra_hir/src/ty.rs
+++ b/crates/ra_hir/src/ty.rs
@@ -858,7 +858,7 @@ impl HirDisplay for ApplicationTy {
                 let name = match def {
                     CallableDef::FunctionId(ff) => f.db.function_data(ff).name.clone(),
                     CallableDef::StructId(s) => {
-                        f.db.struct_data(s.0).name.clone().unwrap_or_else(Name::missing)
+                        f.db.struct_data(s).name.clone().unwrap_or_else(Name::missing)
                     }
                     CallableDef::EnumVariantId(e) => {
                         let enum_data = f.db.enum_data(e.parent);
diff --git a/crates/ra_hir/src/ty/infer/coerce.rs b/crates/ra_hir/src/ty/infer/coerce.rs
index 4b53bba73..bb9a2e427 100644
--- a/crates/ra_hir/src/ty/infer/coerce.rs
+++ b/crates/ra_hir/src/ty/infer/coerce.rs
@@ -246,7 +246,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
                 ty_app!(TypeCtor::Adt(Adt::Struct(struct2)), st2),
             ) if struct1 == struct2 => {
                 let field_tys = self.db.field_types(struct1.id.into());
-                let struct_data = self.db.struct_data(struct1.id.0);
+                let struct_data = self.db.struct_data(struct1.id);
 
                 let mut fields = struct_data.variant_data.fields().iter();
                 let (last_field_id, _data) = fields.next_back()?;
diff --git a/crates/ra_hir/src/ty/infer/expr.rs b/crates/ra_hir/src/ty/infer/expr.rs
index 1d6df2b7a..994a6d7e9 100644
--- a/crates/ra_hir/src/ty/infer/expr.rs
+++ b/crates/ra_hir/src/ty/infer/expr.rs
@@ -263,6 +263,8 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
                                 .clone()
                                 .subst(&a_ty.parameters)
                         }),
+                        // FIXME:
+                        TypeCtor::Adt(Adt::Union(_)) => None,
                         _ => None,
                     },
                     _ => None,
diff --git a/crates/ra_hir/src/ty/lower.rs b/crates/ra_hir/src/ty/lower.rs
index 27cfe00c1..eb51d31bd 100644
--- a/crates/ra_hir/src/ty/lower.rs
+++ b/crates/ra_hir/src/ty/lower.rs
@@ -560,7 +560,8 @@ pub(crate) fn field_types_query(
     variant_id: VariantId,
 ) -> Arc<ArenaMap<LocalStructFieldId, Ty>> {
     let (resolver, var_data) = match variant_id {
-        VariantId::StructId(it) => (it.resolver(db), db.struct_data(it.0).variant_data.clone()),
+        VariantId::StructId(it) => (it.resolver(db), db.struct_data(it).variant_data.clone()),
+        VariantId::UnionId(it) => (it.resolver(db), db.union_data(it).variant_data.clone()),
         VariantId::EnumVariantId(it) => (
             it.parent.resolver(db),
             db.enum_data(it.parent).variants[it.local_id].variant_data.clone(),
@@ -818,7 +819,7 @@ impl CallableDef {
     pub fn krate(self, db: &impl HirDatabase) -> CrateId {
         match self {
             CallableDef::FunctionId(f) => f.lookup(db).module(db).krate,
-            CallableDef::StructId(s) => s.0.module(db).krate,
+            CallableDef::StructId(s) => s.module(db).krate,
             CallableDef::EnumVariantId(e) => e.parent.module(db).krate,
         }
     }
diff --git a/crates/ra_hir_def/src/adt.rs b/crates/ra_hir_def/src/adt.rs
index c9f30923e..0091bfbc3 100644
--- a/crates/ra_hir_def/src/adt.rs
+++ b/crates/ra_hir_def/src/adt.rs
@@ -12,7 +12,7 @@ use ra_syntax::ast::{self, NameOwner, TypeAscriptionOwner};
 
 use crate::{
     db::DefDatabase, trace::Trace, type_ref::TypeRef, AstItemDef, EnumId, HasChildSource,
-    LocalEnumVariantId, LocalStructFieldId, StructOrUnionId, VariantId,
+    LocalEnumVariantId, LocalStructFieldId, StructId, UnionId, VariantId,
 };
 
 /// Note that we use `StructData` for unions as well!
@@ -49,13 +49,25 @@ pub struct StructFieldData {
 }
 
 impl StructData {
-    pub(crate) fn struct_data_query(db: &impl DefDatabase, id: StructOrUnionId) -> Arc<StructData> {
+    pub(crate) fn struct_data_query(db: &impl DefDatabase, id: StructId) -> Arc<StructData> {
         let src = id.source(db);
         let name = src.value.name().map(|n| n.as_name());
         let variant_data = VariantData::new(src.value.kind());
         let variant_data = Arc::new(variant_data);
         Arc::new(StructData { name, variant_data })
     }
+    pub(crate) fn union_data_query(db: &impl DefDatabase, id: UnionId) -> Arc<StructData> {
+        let src = id.source(db);
+        let name = src.value.name().map(|n| n.as_name());
+        let variant_data = VariantData::new(
+            src.value
+                .record_field_def_list()
+                .map(ast::StructKind::Record)
+                .unwrap_or(ast::StructKind::Unit),
+        );
+        let variant_data = Arc::new(variant_data);
+        Arc::new(StructData { name, variant_data })
+    }
 }
 
 impl EnumData {
@@ -137,7 +149,12 @@ impl HasChildSource for VariantId {
                 let src = it.parent.child_source(db);
                 src.map(|map| map[it.local_id].kind())
             }
-            VariantId::StructId(it) => it.0.source(db).map(|it| it.kind()),
+            VariantId::StructId(it) => it.source(db).map(|it| it.kind()),
+            VariantId::UnionId(it) => it.source(db).map(|it| {
+                it.record_field_def_list()
+                    .map(ast::StructKind::Record)
+                    .unwrap_or(ast::StructKind::Unit)
+            }),
         };
         let mut trace = Trace::new_for_map();
         lower_struct(&mut trace, &src.value);
diff --git a/crates/ra_hir_def/src/attr.rs b/crates/ra_hir_def/src/attr.rs
index 53456fc08..298608e27 100644
--- a/crates/ra_hir_def/src/attr.rs
+++ b/crates/ra_hir_def/src/attr.rs
@@ -54,9 +54,9 @@ impl Attrs {
                 Attrs::from_attrs_owner(db, src.map(|it| it as &dyn AttrsOwner))
             }
             AttrDefId::AdtId(it) => match it {
-                AdtId::StructId(it) => attrs_from_ast(it.0.lookup_intern(db).ast_id, db),
+                AdtId::StructId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
                 AdtId::EnumId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
-                AdtId::UnionId(it) => attrs_from_ast(it.0.lookup_intern(db).ast_id, db),
+                AdtId::UnionId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
             },
             AttrDefId::TraitId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
             AttrDefId::MacroDefId(it) => attrs_from_ast(it.ast_id, db),
diff --git a/crates/ra_hir_def/src/db.rs b/crates/ra_hir_def/src/db.rs
index 32adb11bd..ef5611ffc 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, StructOrUnionId, TraitId, TypeAliasId,
-    TypeAliasLoc,
+    ImplId, ItemLoc, ModuleId, StaticId, StaticLoc, StructId, TraitId, TypeAliasId, TypeAliasLoc,
+    UnionId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
@@ -27,7 +27,9 @@ pub trait InternDatabase: SourceDatabase {
     #[salsa::interned]
     fn intern_function(&self, loc: FunctionLoc) -> FunctionId;
     #[salsa::interned]
-    fn intern_struct_or_union(&self, loc: ItemLoc<ast::StructDef>) -> StructOrUnionId;
+    fn intern_struct(&self, loc: ItemLoc<ast::StructDef>) -> StructId;
+    #[salsa::interned]
+    fn intern_union(&self, loc: ItemLoc<ast::UnionDef>) -> UnionId;
     #[salsa::interned]
     fn intern_enum(&self, loc: ItemLoc<ast::EnumDef>) -> EnumId;
     #[salsa::interned]
@@ -57,7 +59,9 @@ pub trait DefDatabase: InternDatabase + AstDatabase {
     fn crate_def_map(&self, krate: CrateId) -> Arc<CrateDefMap>;
 
     #[salsa::invoke(StructData::struct_data_query)]
-    fn struct_data(&self, id: StructOrUnionId) -> Arc<StructData>;
+    fn struct_data(&self, id: StructId) -> Arc<StructData>;
+    #[salsa::invoke(StructData::union_data_query)]
+    fn union_data(&self, id: UnionId) -> Arc<StructData>;
 
     #[salsa::invoke(EnumData::enum_data_query)]
     fn enum_data(&self, e: EnumId) -> Arc<EnumData>;
diff --git a/crates/ra_hir_def/src/docs.rs b/crates/ra_hir_def/src/docs.rs
index 90a8627bc..4749b642f 100644
--- a/crates/ra_hir_def/src/docs.rs
+++ b/crates/ra_hir_def/src/docs.rs
@@ -47,9 +47,9 @@ impl Documentation {
                 }
             }
             AttrDefId::AdtId(it) => match it {
-                AdtId::StructId(it) => docs_from_ast(&it.0.source(db).value),
+                AdtId::StructId(it) => docs_from_ast(&it.source(db).value),
                 AdtId::EnumId(it) => docs_from_ast(&it.source(db).value),
-                AdtId::UnionId(it) => docs_from_ast(&it.0.source(db).value),
+                AdtId::UnionId(it) => docs_from_ast(&it.source(db).value),
             },
             AttrDefId::EnumVariantId(it) => {
                 let src = it.parent.child_source(db);
diff --git a/crates/ra_hir_def/src/generics.rs b/crates/ra_hir_def/src/generics.rs
index 015fe772e..3f94e40e4 100644
--- a/crates/ra_hir_def/src/generics.rs
+++ b/crates/ra_hir_def/src/generics.rs
@@ -60,10 +60,8 @@ impl GenericParams {
         // FIXME: add `: Sized` bound for everything except for `Self` in traits
         match def {
             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)
-            }
-            GenericDefId::AdtId(AdtId::UnionId(it)) => generics.fill(&it.0.source(db).value, start),
+            GenericDefId::AdtId(AdtId::StructId(it)) => generics.fill(&it.source(db).value, start),
+            GenericDefId::AdtId(AdtId::UnionId(it)) => generics.fill(&it.source(db).value, start),
             GenericDefId::AdtId(AdtId::EnumId(it)) => generics.fill(&it.source(db).value, start),
             GenericDefId::TraitId(it) => {
                 // traits get the Self type as an implicit first type parameter
diff --git a/crates/ra_hir_def/src/lib.rs b/crates/ra_hir_def/src/lib.rs
index 8e8c2d749..a88a78b38 100644
--- a/crates/ra_hir_def/src/lib.rs
+++ b/crates/ra_hir_def/src/lib.rs
@@ -141,30 +141,26 @@ impl Lookup for FunctionId {
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct StructOrUnionId(salsa::InternId);
-impl_intern_key!(StructOrUnionId);
-impl AstItemDef<ast::StructDef> for StructOrUnionId {
+pub struct StructId(salsa::InternId);
+impl_intern_key!(StructId);
+impl AstItemDef<ast::StructDef> for StructId {
     fn intern(db: &impl InternDatabase, loc: ItemLoc<ast::StructDef>) -> Self {
-        db.intern_struct_or_union(loc)
+        db.intern_struct(loc)
     }
     fn lookup_intern(self, db: &impl InternDatabase) -> ItemLoc<ast::StructDef> {
-        db.lookup_intern_struct_or_union(self)
+        db.lookup_intern_struct(self)
     }
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct StructId(pub StructOrUnionId);
-impl From<StructId> for StructOrUnionId {
-    fn from(id: StructId) -> StructOrUnionId {
-        id.0
+pub struct UnionId(salsa::InternId);
+impl_intern_key!(UnionId);
+impl AstItemDef<ast::UnionDef> for UnionId {
+    fn intern(db: &impl InternDatabase, loc: ItemLoc<ast::UnionDef>) -> Self {
+        db.intern_union(loc)
     }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct UnionId(pub StructOrUnionId);
-impl From<UnionId> for StructOrUnionId {
-    fn from(id: UnionId) -> StructOrUnionId {
-        id.0
+    fn lookup_intern(self, db: &impl InternDatabase) -> ItemLoc<ast::UnionDef> {
+        db.lookup_intern_union(self)
     }
 }
 
@@ -435,6 +431,7 @@ impl_froms!(
 pub enum VariantId {
     EnumVariantId(EnumVariantId),
     StructId(StructId),
+    UnionId(UnionId),
 }
 impl_froms!(VariantId: EnumVariantId, StructId);
 
@@ -485,8 +482,8 @@ impl HasModule for ConstLoc {
 impl HasModule for AdtId {
     fn module(&self, db: &impl db::DefDatabase) -> ModuleId {
         match self {
-            AdtId::StructId(it) => it.0.module(db),
-            AdtId::UnionId(it) => it.0.module(db),
+            AdtId::StructId(it) => it.module(db),
+            AdtId::UnionId(it) => it.module(db),
             AdtId::EnumId(it) => it.module(db),
         }
     }
diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index 41becf8df..4ff6f72cf 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -25,7 +25,7 @@ use crate::{
     per_ns::PerNs,
     AdtId, AstId, AstItemDef, ConstLoc, ContainerId, EnumId, EnumVariantId, FunctionLoc, ImplId,
     Intern, LocalImportId, LocalModuleId, LocationCtx, ModuleDefId, ModuleId, StaticLoc, StructId,
-    StructOrUnionId, TraitId, TypeAliasLoc, UnionId,
+    TraitId, TypeAliasLoc, UnionId,
 };
 
 pub(super) fn collect_defs(db: &impl DefDatabase, mut def_map: CrateDefMap) -> CrateDefMap {
@@ -698,14 +698,12 @@ where
                 PerNs::values(def.into())
             }
             raw::DefKind::Struct(ast_id) => {
-                let id = StructOrUnionId::from_ast_id(ctx, ast_id).into();
-                let s = StructId(id).into();
-                PerNs::both(s, s)
+                let id = StructId::from_ast_id(ctx, ast_id).into();
+                PerNs::both(id, id)
             }
             raw::DefKind::Union(ast_id) => {
-                let id = StructOrUnionId::from_ast_id(ctx, ast_id).into();
-                let u = UnionId(id).into();
-                PerNs::both(u, u)
+                let id = UnionId::from_ast_id(ctx, ast_id).into();
+                PerNs::both(id, id)
             }
             raw::DefKind::Enum(ast_id) => PerNs::types(EnumId::from_ast_id(ctx, ast_id).into()),
             raw::DefKind::Const(ast_id) => {
diff --git a/crates/ra_hir_def/src/nameres/raw.rs b/crates/ra_hir_def/src/nameres/raw.rs
index 401af031c..6eb106094 100644
--- a/crates/ra_hir_def/src/nameres/raw.rs
+++ b/crates/ra_hir_def/src/nameres/raw.rs
@@ -176,7 +176,7 @@ pub(super) struct DefData {
 pub(super) enum DefKind {
     Function(FileAstId<ast::FnDef>),
     Struct(FileAstId<ast::StructDef>),
-    Union(FileAstId<ast::StructDef>),
+    Union(FileAstId<ast::UnionDef>),
     Enum(FileAstId<ast::EnumDef>),
     Const(FileAstId<ast::ConstDef>),
     Static(FileAstId<ast::StaticDef>),
@@ -246,11 +246,12 @@ impl RawItemsCollector {
             ast::ModuleItem::StructDef(it) => {
                 let id = self.source_ast_id_map.ast_id(&it);
                 let name = it.name();
-                if it.is_union() {
-                    (DefKind::Union(id), name)
-                } else {
-                    (DefKind::Struct(id), name)
-                }
+                (DefKind::Struct(id), name)
+            }
+            ast::ModuleItem::UnionDef(it) => {
+                let id = self.source_ast_id_map.ast_id(&it);
+                let name = it.name();
+                (DefKind::Union(id), name)
             }
             ast::ModuleItem::EnumDef(it) => {
                 (DefKind::Enum(self.source_ast_id_map.ast_id(&it)), it.name())
diff --git a/crates/ra_hir_def/src/nameres/tests.rs b/crates/ra_hir_def/src/nameres/tests.rs
index f502f1cb3..87fcd617c 100644
--- a/crates/ra_hir_def/src/nameres/tests.rs
+++ b/crates/ra_hir_def/src/nameres/tests.rs
@@ -82,6 +82,12 @@ fn crate_def_map_smoke_test() {
 
         //- /foo/bar.rs
         pub struct Baz;
+
+        union U {
+            to_be: bool,
+            not_to_be: u8,
+        }
+
         enum E { V }
         ",
     );
@@ -99,6 +105,7 @@ fn crate_def_map_smoke_test() {
         ⋮crate::foo::bar
         ⋮Baz: t v
         ⋮E: t
+        ⋮U: t v
     "###)
 }
 
diff --git a/crates/ra_ide_api/src/display/short_label.rs b/crates/ra_ide_api/src/display/short_label.rs
index 5d2bce3d2..9ffc9b980 100644
--- a/crates/ra_ide_api/src/display/short_label.rs
+++ b/crates/ra_ide_api/src/display/short_label.rs
@@ -19,6 +19,12 @@ impl ShortLabel for ast::StructDef {
     }
 }
 
+impl ShortLabel for ast::UnionDef {
+    fn short_label(&self) -> Option<String> {
+        short_label_from_node(self, "union ")
+    }
+}
+
 impl ShortLabel for ast::EnumDef {
     fn short_label(&self) -> Option<String> {
         short_label_from_node(self, "enum ")
diff --git a/crates/ra_ide_api/src/impls.rs b/crates/ra_ide_api/src/impls.rs
index 3e3012559..2b3100fc3 100644
--- a/crates/ra_ide_api/src/impls.rs
+++ b/crates/ra_ide_api/src/impls.rs
@@ -49,6 +49,10 @@ fn impls_for_def(
             let src = hir::Source { file_id: position.file_id.into(), value: def.clone() };
             hir::Enum::from_source(db, src)?.ty(db)
         }
+        ast::NominalDef::UnionDef(def) => {
+            let src = hir::Source { file_id: position.file_id.into(), value: def.clone() };
+            hir::Union::from_source(db, src)?.ty(db)
+        }
     };
 
     let krate = module.krate();
diff --git a/crates/ra_parser/src/grammar/items.rs b/crates/ra_parser/src/grammar/items.rs
index 85f7eeb00..370990e21 100644
--- a/crates/ra_parser/src/grammar/items.rs
+++ b/crates/ra_parser/src/grammar/items.rs
@@ -1,13 +1,13 @@
 //! FIXME: write short doc here
 
 mod consts;
-mod nominal;
+mod adt;
 mod traits;
 mod use_item;
 
 pub(crate) use self::{
+    adt::{enum_variant_list, record_field_def_list},
     expressions::{match_arm_list, record_field_list},
-    nominal::{enum_variant_list, record_field_def_list},
     traits::{impl_item_list, trait_item_list},
     use_item::use_tree_list,
 };
@@ -247,7 +247,7 @@ fn items_without_modifiers(p: &mut Parser, m: Marker) -> Result<(), Marker> {
             //     a: i32,
             //     b: f32,
             // }
-            nominal::struct_def(p, m, T![struct]);
+            adt::struct_def(p, m);
         }
         IDENT if p.at_contextual_kw("union") && p.nth(1) == IDENT => {
             // test union_items
@@ -256,9 +256,9 @@ fn items_without_modifiers(p: &mut Parser, m: Marker) -> Result<(), Marker> {
             //     a: i32,
             //     b: f32,
             // }
-            nominal::struct_def(p, m, T![union]);
+            adt::union_def(p, m);
         }
-        T![enum] => nominal::enum_def(p, m),
+        T![enum] => adt::enum_def(p, m),
         T![use] => use_item::use_item(p, m),
         T![const] if (la == IDENT || la == T![_] || la == T![mut]) => consts::const_def(p, m),
         T![static] => consts::static_def(p, m),
diff --git a/crates/ra_parser/src/grammar/items/nominal.rs b/crates/ra_parser/src/grammar/items/adt.rs
index 9d8fb8486..c777bc9d0 100644
--- a/crates/ra_parser/src/grammar/items/nominal.rs
+++ b/crates/ra_parser/src/grammar/items/adt.rs
@@ -2,10 +2,19 @@
 
 use super::*;
 
-pub(super) fn struct_def(p: &mut Parser, m: Marker, kind: SyntaxKind) {
-    assert!(p.at(T![struct]) || p.at_contextual_kw("union"));
-    p.bump_remap(kind);
+pub(super) fn struct_def(p: &mut Parser, m: Marker) {
+    assert!(p.at(T![struct]));
+    p.bump(T![struct]);
+    struct_or_union(p, m, T![struct], STRUCT_DEF);
+}
+
+pub(super) fn union_def(p: &mut Parser, m: Marker) {
+    assert!(p.at_contextual_kw("union"));
+    p.bump_remap(T![union]);
+    struct_or_union(p, m, T![union], UNION_DEF);
+}
 
+fn struct_or_union(p: &mut Parser, m: Marker, kw: SyntaxKind, def: SyntaxKind) {
     name_r(p, ITEM_RECOVERY_SET);
     type_params::opt_type_param_list(p);
     match p.current() {
@@ -22,11 +31,11 @@ pub(super) fn struct_def(p: &mut Parser, m: Marker, kind: SyntaxKind) {
                 }
             }
         }
-        T![;] if kind == T![struct] => {
+        T![;] if kw == T![struct] => {
             p.bump(T![;]);
         }
         T!['{'] => record_field_def_list(p),
-        T!['('] if kind == T![struct] => {
+        T!['('] if kw == T![struct] => {
             tuple_field_def_list(p);
             // test tuple_struct_where
             // struct Test<T>(T) where T: Clone;
@@ -34,14 +43,14 @@ pub(super) fn struct_def(p: &mut Parser, m: Marker, kind: SyntaxKind) {
             type_params::opt_where_clause(p);
             p.expect(T![;]);
         }
-        _ if kind == T![struct] => {
+        _ if kw == T![struct] => {
             p.error("expected `;`, `{`, or `(`");
         }
         _ => {
             p.error("expected `{`");
         }
     }
-    m.complete(p, STRUCT_DEF);
+    m.complete(p, def);
 }
 
 pub(super) fn enum_def(p: &mut Parser, m: Marker) {
diff --git a/crates/ra_parser/src/syntax_kind/generated.rs b/crates/ra_parser/src/syntax_kind/generated.rs
index 96b5bce88..fe0fcdb33 100644
--- a/crates/ra_parser/src/syntax_kind/generated.rs
+++ b/crates/ra_parser/src/syntax_kind/generated.rs
@@ -122,6 +122,7 @@ pub enum SyntaxKind {
     R_DOLLAR,
     SOURCE_FILE,
     STRUCT_DEF,
+    UNION_DEF,
     ENUM_DEF,
     FN_DEF,
     RET_TYPE,
diff --git a/crates/ra_syntax/src/ast/extensions.rs b/crates/ra_syntax/src/ast/extensions.rs
index 513ed7920..a8f625176 100644
--- a/crates/ra_syntax/src/ast/extensions.rs
+++ b/crates/ra_syntax/src/ast/extensions.rs
@@ -196,17 +196,6 @@ impl StructKind {
 }
 
 impl ast::StructDef {
-    pub fn is_union(&self) -> bool {
-        for child in self.syntax().children_with_tokens() {
-            match child.kind() {
-                T![struct] => return false,
-                T![union] => return true,
-                _ => (),
-            }
-        }
-        false
-    }
-
     pub fn kind(&self) -> StructKind {
         StructKind::from_node(self)
     }
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index de506d7cd..c06076e3d 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -1856,6 +1856,7 @@ impl Module {
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum ModuleItem {
     StructDef(StructDef),
+    UnionDef(UnionDef),
     EnumDef(EnumDef),
     FnDef(FnDef),
     TraitDef(TraitDef),
@@ -1872,6 +1873,11 @@ impl From<StructDef> for ModuleItem {
         ModuleItem::StructDef(node)
     }
 }
+impl From<UnionDef> for ModuleItem {
+    fn from(node: UnionDef) -> ModuleItem {
+        ModuleItem::UnionDef(node)
+    }
+}
 impl From<EnumDef> for ModuleItem {
     fn from(node: EnumDef) -> ModuleItem {
         ModuleItem::EnumDef(node)
@@ -1925,14 +1931,15 @@ impl From<Module> for ModuleItem {
 impl AstNode for ModuleItem {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
-            STRUCT_DEF | ENUM_DEF | FN_DEF | TRAIT_DEF | TYPE_ALIAS_DEF | IMPL_BLOCK | USE_ITEM
-            | EXTERN_CRATE_ITEM | CONST_DEF | STATIC_DEF | MODULE => true,
+            STRUCT_DEF | UNION_DEF | ENUM_DEF | FN_DEF | TRAIT_DEF | TYPE_ALIAS_DEF
+            | IMPL_BLOCK | USE_ITEM | EXTERN_CRATE_ITEM | CONST_DEF | STATIC_DEF | MODULE => true,
             _ => false,
         }
     }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
         let res = match syntax.kind() {
             STRUCT_DEF => ModuleItem::StructDef(StructDef { syntax }),
+            UNION_DEF => ModuleItem::UnionDef(UnionDef { syntax }),
             ENUM_DEF => ModuleItem::EnumDef(EnumDef { syntax }),
             FN_DEF => ModuleItem::FnDef(FnDef { syntax }),
             TRAIT_DEF => ModuleItem::TraitDef(TraitDef { syntax }),
@@ -1950,6 +1957,7 @@ impl AstNode for ModuleItem {
     fn syntax(&self) -> &SyntaxNode {
         match self {
             ModuleItem::StructDef(it) => &it.syntax,
+            ModuleItem::UnionDef(it) => &it.syntax,
             ModuleItem::EnumDef(it) => &it.syntax,
             ModuleItem::FnDef(it) => &it.syntax,
             ModuleItem::TraitDef(it) => &it.syntax,
@@ -2038,6 +2046,7 @@ impl NeverType {}
 pub enum NominalDef {
     StructDef(StructDef),
     EnumDef(EnumDef),
+    UnionDef(UnionDef),
 }
 impl From<StructDef> for NominalDef {
     fn from(node: StructDef) -> NominalDef {
@@ -2049,10 +2058,15 @@ impl From<EnumDef> for NominalDef {
         NominalDef::EnumDef(node)
     }
 }
+impl From<UnionDef> for NominalDef {
+    fn from(node: UnionDef) -> NominalDef {
+        NominalDef::UnionDef(node)
+    }
+}
 impl AstNode for NominalDef {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
-            STRUCT_DEF | ENUM_DEF => true,
+            STRUCT_DEF | ENUM_DEF | UNION_DEF => true,
             _ => false,
         }
     }
@@ -2060,6 +2074,7 @@ impl AstNode for NominalDef {
         let res = match syntax.kind() {
             STRUCT_DEF => NominalDef::StructDef(StructDef { syntax }),
             ENUM_DEF => NominalDef::EnumDef(EnumDef { syntax }),
+            UNION_DEF => NominalDef::UnionDef(UnionDef { syntax }),
             _ => return None,
         };
         Some(res)
@@ -2068,6 +2083,7 @@ impl AstNode for NominalDef {
         match self {
             NominalDef::StructDef(it) => &it.syntax,
             NominalDef::EnumDef(it) => &it.syntax,
+            NominalDef::UnionDef(it) => &it.syntax,
         }
     }
 }
@@ -3789,6 +3805,38 @@ impl AstNode for TypeRef {
 }
 impl TypeRef {}
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct UnionDef {
+    pub(crate) syntax: SyntaxNode,
+}
+impl AstNode for UnionDef {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            UNION_DEF => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        &self.syntax
+    }
+}
+impl ast::VisibilityOwner for UnionDef {}
+impl ast::NameOwner for UnionDef {}
+impl ast::TypeParamsOwner for UnionDef {}
+impl ast::AttrsOwner for UnionDef {}
+impl ast::DocCommentsOwner for UnionDef {}
+impl UnionDef {
+    pub fn record_field_def_list(&self) -> Option<RecordFieldDefList> {
+        AstChildren::new(&self.syntax).next()
+    }
+}
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct UseItem {
     pub(crate) syntax: SyntaxNode,
 }
diff --git a/crates/ra_syntax/src/grammar.ron b/crates/ra_syntax/src/grammar.ron
index 88d1dc109..d1be40abe 100644
--- a/crates/ra_syntax/src/grammar.ron
+++ b/crates/ra_syntax/src/grammar.ron
@@ -126,6 +126,7 @@ Grammar(
         "SOURCE_FILE",
 
         "STRUCT_DEF",
+        "UNION_DEF",
         "ENUM_DEF",
         "FN_DEF",
         "RET_TYPE",
@@ -285,6 +286,16 @@ Grammar(
                 "DocCommentsOwner"
             ]
         ),
+        "UnionDef": (
+            traits: [
+                "VisibilityOwner",
+                "NameOwner",
+                "TypeParamsOwner",
+                "AttrsOwner",
+                "DocCommentsOwner"
+            ],
+            options: ["RecordFieldDefList"],
+        ),
         "RecordFieldDefList": (collections: [("fields", "RecordFieldDef")]),
         "RecordFieldDef": (
             traits: [
@@ -388,7 +399,7 @@ Grammar(
         ]),
 
         "NominalDef": (
-            enum: ["StructDef", "EnumDef"],
+            enum: ["StructDef", "EnumDef", "UnionDef"],
             traits: [
                 "NameOwner",
                 "TypeParamsOwner",
@@ -396,9 +407,9 @@ Grammar(
             ],
         ),
         "ModuleItem": (
-            enum: ["StructDef", "EnumDef", "FnDef", "TraitDef", "TypeAliasDef", "ImplBlock",
+            enum: ["StructDef", "UnionDef", "EnumDef", "FnDef", "TraitDef", "TypeAliasDef", "ImplBlock",
                    "UseItem", "ExternCrateItem", "ConstDef", "StaticDef", "Module" ],
-            traits: ["AttrsOwner"]
+            traits: ["AttrsOwner"],
         ),
         "ImplItem": (
             enum: ["FnDef", "TypeAliasDef", "ConstDef"],
diff --git a/crates/ra_syntax/test_data/parser/inline/ok/0068_union_items.txt b/crates/ra_syntax/test_data/parser/inline/ok/0068_union_items.txt
index f9ace02ee..9d7982684 100644
--- a/crates/ra_syntax/test_data/parser/inline/ok/0068_union_items.txt
+++ b/crates/ra_syntax/test_data/parser/inline/ok/0068_union_items.txt
@@ -1,5 +1,5 @@
 SOURCE_FILE@[0; 51)
-  STRUCT_DEF@[0; 12)
+  UNION_DEF@[0; 12)
     UNION_KW@[0; 5) "union"
     WHITESPACE@[5; 6) " "
     NAME@[6; 9)
@@ -9,7 +9,7 @@ SOURCE_FILE@[0; 51)
       L_CURLY@[10; 11) "{"
       R_CURLY@[11; 12) "}"
   WHITESPACE@[12; 13) "\n"
-  STRUCT_DEF@[13; 50)
+  UNION_DEF@[13; 50)
     UNION_KW@[13; 18) "union"
     WHITESPACE@[18; 19) " "
     NAME@[19; 22)
diff --git a/crates/ra_syntax/test_data/parser/ok/0035_weird_exprs.txt b/crates/ra_syntax/test_data/parser/ok/0035_weird_exprs.txt
index 3260cc589..90538b90d 100644
--- a/crates/ra_syntax/test_data/parser/ok/0035_weird_exprs.txt
+++ b/crates/ra_syntax/test_data/parser/ok/0035_weird_exprs.txt
@@ -1592,7 +1592,7 @@ SOURCE_FILE@[0; 3813)
       BLOCK@[2845; 2906)
         L_CURLY@[2845; 2846) "{"
         WHITESPACE@[2846; 2851) "\n    "
-        STRUCT_DEF@[2851; 2904)
+        UNION_DEF@[2851; 2904)
           UNION_KW@[2851; 2856) "union"
           WHITESPACE@[2856; 2857) " "
           NAME@[2857; 2862)