6 files changed, 23 insertions, 6 deletions

diff --git a/crates/hir_def/src/body/lower.rs b/crates/hir_def/src/body/lower.rs
index 30ac12a12..2d91bb21f 100644
--- a/crates/hir_def/src/body/lower.rs
+++ b/crates/hir_def/src/body/lower.rs
@@ -239,7 +239,10 @@ impl ExprCollector<'_> {
                     None => self.missing_expr(),
                 },
                 // FIXME: we need to record these effects somewhere...
-                ast::Effect::Async(_) => self.collect_block_opt(e.block_expr()),
+                ast::Effect::Async(_) => {
+                    let body = self.collect_block_opt(e.block_expr());
+                    self.alloc_expr(Expr::Async { body }, syntax_ptr)
+                }
             },
             ast::Expr::BlockExpr(e) => self.collect_block(e),
             ast::Expr::LoopExpr(e) => {
@@ -835,8 +838,12 @@ impl ExprCollector<'_> {
 
                 Pat::Missing
             }
+            ast::Pat::BoxPat(boxpat) => {
+                let inner = self.collect_pat_opt(boxpat.pat());
+                Pat::Box { inner }
+            }
             // FIXME: implement
-            ast::Pat::BoxPat(_) | ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
+            ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
         };
         let ptr = AstPtr::new(&pat);
         self.alloc_pat(pattern, Either::Left(ptr))
diff --git a/crates/hir_def/src/data.rs b/crates/hir_def/src/data.rs
index 9a8eb4ede..6190906da 100644
--- a/crates/hir_def/src/data.rs
+++ b/crates/hir_def/src/data.rs
@@ -54,6 +54,7 @@ pub struct TypeAliasData {
     pub name: Name,
     pub type_ref: Option<TypeRef>,
     pub visibility: RawVisibility,
+    pub is_extern: bool,
     /// Bounds restricting the type alias itself (eg. `type Ty: Bound;` in a trait or impl).
     pub bounds: Vec<TypeBound>,
 }
@@ -71,6 +72,7 @@ impl TypeAliasData {
             name: typ.name.clone(),
             type_ref: typ.type_ref.clone(),
             visibility: item_tree[typ.visibility].clone(),
+            is_extern: typ.is_extern,
             bounds: typ.bounds.to_vec(),
         })
     }
diff --git a/crates/hir_def/src/expr.rs b/crates/hir_def/src/expr.rs
index c94b3a36f..e5d740a36 100644
--- a/crates/hir_def/src/expr.rs
+++ b/crates/hir_def/src/expr.rs
@@ -111,6 +111,9 @@ pub enum Expr {
     TryBlock {
         body: ExprId,
     },
+    Async {
+        body: ExprId,
+    },
     Cast {
         expr: ExprId,
         type_ref: TypeRef,
@@ -250,7 +253,7 @@ impl Expr {
                     f(*expr);
                 }
             }
-            Expr::TryBlock { body } | Expr::Unsafe { body } => f(*body),
+            Expr::TryBlock { body } | Expr::Unsafe { body } | Expr::Async { body } => f(*body),
             Expr::Loop { body, .. } => f(*body),
             Expr::While { condition, body, .. } => {
                 f(*condition);
@@ -395,6 +398,7 @@ pub enum Pat {
     Bind { mode: BindingAnnotation, name: Name, subpat: Option<PatId> },
     TupleStruct { path: Option<Path>, args: Vec<PatId>, ellipsis: Option<usize> },
     Ref { pat: PatId, mutability: Mutability },
+    Box { inner: PatId },
 }
 
 impl Pat {
@@ -415,6 +419,7 @@ impl Pat {
             Pat::Record { args, .. } => {
                 args.iter().map(|f| f.pat).for_each(f);
             }
+            Pat::Box { inner } => f(*inner),
         }
     }
 }
diff --git a/crates/hir_def/src/item_tree.rs b/crates/hir_def/src/item_tree.rs
index e14722cae..52abb8e7f 100644
--- a/crates/hir_def/src/item_tree.rs
+++ b/crates/hir_def/src/item_tree.rs
@@ -592,6 +592,7 @@ pub struct TypeAlias {
     pub bounds: Box<[TypeBound]>,
     pub generic_params: GenericParamsId,
     pub type_ref: Option<TypeRef>,
+    pub is_extern: bool,
     pub ast_id: FileAstId<ast::TypeAlias>,
 }
 
diff --git a/crates/hir_def/src/item_tree/lower.rs b/crates/hir_def/src/item_tree/lower.rs
index 6a503d785..d93377c3b 100644
--- a/crates/hir_def/src/item_tree/lower.rs
+++ b/crates/hir_def/src/item_tree/lower.rs
@@ -364,6 +364,7 @@ impl Ctx {
             generic_params,
             type_ref,
             ast_id,
+            is_extern: false,
         };
         Some(id(self.data().type_aliases.alloc(res)))
     }
@@ -558,8 +559,9 @@ impl Ctx {
                             statik.into()
                         }
                         ast::ExternItem::TypeAlias(ty) => {
-                            let id = self.lower_type_alias(&ty)?;
-                            id.into()
+                            let foreign_ty = self.lower_type_alias(&ty)?;
+                            self.data().type_aliases[foreign_ty.index].is_extern = true;
+                            foreign_ty.into()
                         }
                         ast::ExternItem::MacroCall(_) => return None,
                     };
diff --git a/crates/hir_def/src/item_tree/tests.rs b/crates/hir_def/src/item_tree/tests.rs
index 620e697d4..eed3d0d6f 100644
--- a/crates/hir_def/src/item_tree/tests.rs
+++ b/crates/hir_def/src/item_tree/tests.rs
@@ -236,7 +236,7 @@ fn smoke() {
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("on_trait"))] }, input: None }]) }]
             Trait { name: Name(Text("Tr")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(0), auto: false, items: [TypeAlias(Idx::<TypeAlias>(0)), Const(Idx::<Const>(0)), Function(Idx::<Function>(0)), Function(Idx::<Function>(1))], ast_id: FileAstId::<syntax::ast::generated::nodes::Trait>(2) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_ty"))] }, input: None }]) }]
-            > TypeAlias { name: Name(Text("AssocTy")), visibility: RawVisibilityId("pub(self)"), bounds: [Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Tr"))] }, generic_args: [Some(GenericArgs { args: [Type(Tuple([]))], has_self_type: false, bindings: [] })] })], generic_params: GenericParamsId(4294967295), type_ref: None, ast_id: FileAstId::<syntax::ast::generated::nodes::TypeAlias>(8) }
+            > TypeAlias { name: Name(Text("AssocTy")), visibility: RawVisibilityId("pub(self)"), bounds: [Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Tr"))] }, generic_args: [Some(GenericArgs { args: [Type(Tuple([]))], has_self_type: false, bindings: [] })] })], generic_params: GenericParamsId(4294967295), type_ref: None, is_extern: false, ast_id: FileAstId::<syntax::ast::generated::nodes::TypeAlias>(8) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_const"))] }, input: None }]) }]
             > Const { name: Some(Name(Text("CONST"))), visibility: RawVisibilityId("pub(self)"), type_ref: Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("u8"))] }, generic_args: [None] }), ast_id: FileAstId::<syntax::ast::generated::nodes::Const>(9) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_method"))] }, input: None }]) }]