5 files changed, 34 insertions, 15 deletions

diff --git a/crates/ra_hir_def/src/data.rs b/crates/ra_hir_def/src/data.rs
index aa335f1e3..88a8ef9bf 100644
--- a/crates/ra_hir_def/src/data.rs
+++ b/crates/ra_hir_def/src/data.rs
@@ -27,6 +27,7 @@ pub struct FunctionData {
     /// can be called as a method.
     pub has_self_param: bool,
     pub is_unsafe: bool,
+    pub is_varargs: bool,
     pub visibility: RawVisibility,
 }
 
@@ -43,6 +44,7 @@ impl FunctionData {
             attrs: item_tree.attrs(ModItem::from(loc.id.value).into()).clone(),
             has_self_param: func.has_self_param,
             is_unsafe: func.is_unsafe,
+            is_varargs: func.is_varargs,
             visibility: item_tree[func.visibility].clone(),
         })
     }
diff --git a/crates/ra_hir_def/src/item_tree.rs b/crates/ra_hir_def/src/item_tree.rs
index 3e603bd55..da79d8ffd 100644
--- a/crates/ra_hir_def/src/item_tree.rs
+++ b/crates/ra_hir_def/src/item_tree.rs
@@ -503,6 +503,7 @@ pub struct Function {
     pub has_self_param: bool,
     pub is_unsafe: bool,
     pub params: Box<[TypeRef]>,
+    pub is_varargs: bool,
     pub ret_type: TypeRef,
     pub ast_id: FileAstId<ast::FnDef>,
 }
diff --git a/crates/ra_hir_def/src/item_tree/lower.rs b/crates/ra_hir_def/src/item_tree/lower.rs
index 4182a9e3b..f79b8fca3 100644
--- a/crates/ra_hir_def/src/item_tree/lower.rs
+++ b/crates/ra_hir_def/src/item_tree/lower.rs
@@ -313,6 +313,14 @@ impl Ctx {
                 params.push(type_ref);
             }
         }
+
+        let mut is_varargs = false;
+        if let Some(params) = func.param_list() {
+            if let Some(last) = params.params().last() {
+                is_varargs = last.dotdotdot_token().is_some();
+            }
+        }
+
         let ret_type = match func.ret_type().and_then(|rt| rt.type_ref()) {
             Some(type_ref) => TypeRef::from_ast(&self.body_ctx, type_ref),
             _ => TypeRef::unit(),
@@ -334,6 +342,7 @@ impl Ctx {
             has_self_param,
             is_unsafe: func.unsafe_token().is_some(),
             params: params.into_boxed_slice(),
+            is_varargs,
             ret_type,
             ast_id,
         };
diff --git a/crates/ra_hir_def/src/item_tree/tests.rs b/crates/ra_hir_def/src/item_tree/tests.rs
index a0431dbce..f26982985 100644
--- a/crates/ra_hir_def/src/item_tree/tests.rs
+++ b/crates/ra_hir_def/src/item_tree/tests.rs
@@ -240,9 +240,9 @@ fn smoke() {
             > #[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::<ra_syntax::ast::generated::nodes::ConstDef>(9) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_method"))] }, input: None }]) }]
-            > Function { name: Name(Text("method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Shared)], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(10) }
+            > Function { name: Name(Text("method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Shared)], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(10) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_dfl_method"))] }, input: None }]) }]
-            > Function { name: Name(Text("dfl_method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Mut)], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(11) }
+            > Function { name: Name(Text("dfl_method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Mut)], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(11) }
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("struct0"))] }, input: None }]) }]
             Struct { name: Name(Text("Struct0")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(1), fields: Unit, ast_id: FileAstId::<ra_syntax::ast::generated::nodes::StructDef>(3), kind: Unit }
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("struct1"))] }, input: None }]) }]
@@ -275,12 +275,12 @@ fn simple_inner_items() {
 
             top-level items:
             Impl { generic_params: GenericParamsId(0), target_trait: Some(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("D"))] }, generic_args: [None] })), target_type: Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Response"))] }, generic_args: [Some(GenericArgs { args: [Type(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("T"))] }, generic_args: [None] }))], has_self_type: false, bindings: [] })] }), is_negative: false, items: [Function(Idx::<Function>(1))], ast_id: FileAstId::<ra_syntax::ast::generated::nodes::ImplDef>(0) }
-            > Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
+            > Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
 
             inner items:
 
             for AST FileAstId::<ra_syntax::ast::generated::nodes::ModuleItem>(2):
-            Function { name: Name(Text("end")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(1), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
+            Function { name: Name(Text("end")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(1), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
 
         "#]],
     );
@@ -303,9 +303,9 @@ fn extern_attrs() {
 
             top-level items:
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_a"))] }, input: None }, Attr { path: ModPath { kind: Plain, segments: [Name(Text("block_attr"))] }, input: None }]) }]
-            Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: true, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
+            Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: true, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_b"))] }, input: None }, Attr { path: ModPath { kind: Plain, segments: [Name(Text("block_attr"))] }, input: None }]) }]
-            Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: true, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
+            Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: true, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
         "##]],
     );
 }
@@ -329,9 +329,9 @@ fn trait_attrs() {
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("trait_attr"))] }, input: None }]) }]
             Trait { name: Name(Text("Tr")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(0), auto: false, items: [Function(Idx::<Function>(0)), Function(Idx::<Function>(1))], ast_id: FileAstId::<ra_syntax::ast::generated::nodes::TraitDef>(0) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_a"))] }, input: None }]) }]
-            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
+            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_b"))] }, input: None }]) }]
-            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
+            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
         "##]],
     );
 }
@@ -355,9 +355,9 @@ fn impl_attrs() {
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("impl_attr"))] }, input: None }]) }]
             Impl { generic_params: GenericParamsId(4294967295), target_trait: None, target_type: Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Ty"))] }, generic_args: [None] }), is_negative: false, items: [Function(Idx::<Function>(0)), Function(Idx::<Function>(1))], ast_id: FileAstId::<ra_syntax::ast::generated::nodes::ImplDef>(0) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_a"))] }, input: None }]) }]
-            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
+            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_b"))] }, input: None }]) }]
-            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
+            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(2) }
         "##]],
     );
 }
@@ -408,13 +408,13 @@ fn inner_item_attrs() {
             inner attrs: Attrs { entries: None }
 
             top-level items:
-            Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(0) }
+            Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(0) }
 
             inner items:
 
             for AST FileAstId::<ra_syntax::ast::generated::nodes::ModuleItem>(1):
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("on_inner"))] }, input: None }]) }]
-            Function { name: Name(Text("inner")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
+            Function { name: Name(Text("inner")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<ra_syntax::ast::generated::nodes::FnDef>(1) }
 
         "##]],
     );
diff --git a/crates/ra_hir_def/src/type_ref.rs b/crates/ra_hir_def/src/type_ref.rs
index 86a77b704..e90b2a0b9 100644
--- a/crates/ra_hir_def/src/type_ref.rs
+++ b/crates/ra_hir_def/src/type_ref.rs
@@ -63,7 +63,7 @@ pub enum TypeRef {
     Array(Box<TypeRef> /*, Expr*/),
     Slice(Box<TypeRef>),
     /// A fn pointer. Last element of the vector is the return type.
-    Fn(Vec<TypeRef>),
+    Fn(Vec<TypeRef>, bool /*varargs*/),
     // For
     ImplTrait(Vec<TypeBound>),
     DynTrait(Vec<TypeBound>),
@@ -118,7 +118,12 @@ impl TypeRef {
                     .and_then(|rt| rt.type_ref())
                     .map(|it| TypeRef::from_ast(ctx, it))
                     .unwrap_or_else(|| TypeRef::Tuple(Vec::new()));
+                let mut is_varargs = false;
                 let mut params = if let Some(pl) = inner.param_list() {
+                    if let Some(param) = pl.params().last() {
+                        is_varargs = param.dotdotdot_token().is_some();
+                    }
+
                     pl.params()
                         .map(|p| p.ascribed_type())
                         .map(|it| TypeRef::from_ast_opt(&ctx, it))
@@ -127,7 +132,7 @@ impl TypeRef {
                     Vec::new()
                 };
                 params.push(ret_ty);
-                TypeRef::Fn(params)
+                TypeRef::Fn(params, is_varargs)
             }
             // for types are close enough for our purposes to the inner type for now...
             ast::TypeRef::ForType(inner) => TypeRef::from_ast_opt(&ctx, inner.type_ref()),
@@ -158,7 +163,9 @@ impl TypeRef {
         fn go(type_ref: &TypeRef, f: &mut impl FnMut(&TypeRef)) {
             f(type_ref);
             match type_ref {
-                TypeRef::Fn(types) | TypeRef::Tuple(types) => types.iter().for_each(|t| go(t, f)),
+                TypeRef::Fn(types, _) | TypeRef::Tuple(types) => {
+                    types.iter().for_each(|t| go(t, f))
+                }
                 TypeRef::RawPtr(type_ref, _)
                 | TypeRef::Reference(type_ref, _)
                 | TypeRef::Array(type_ref)