3 files changed, 16 insertions, 7 deletions

diff --git a/crates/ra_hir_def/src/data.rs b/crates/ra_hir_def/src/data.rs
index 88a8ef9bf..2a26b0183 100644
--- a/crates/ra_hir_def/src/data.rs
+++ b/crates/ra_hir_def/src/data.rs
@@ -10,7 +10,7 @@ use crate::{
     attr::Attrs,
     body::Expander,
     db::DefDatabase,
-    item_tree::{AssocItem, ItemTreeId, ModItem},
+    item_tree::{AssocItem, ItemTreeId, ModItem, SelfParam},
     type_ref::{TypeBound, TypeRef},
     visibility::RawVisibility,
     AssocContainerId, AssocItemId, ConstId, ConstLoc, FunctionId, FunctionLoc, HasModule, ImplId,
@@ -25,7 +25,7 @@ pub struct FunctionData {
     pub attrs: Attrs,
     /// True if the first param is `self`. This is relevant to decide whether this
     /// can be called as a method.
-    pub has_self_param: bool,
+    pub self_param: Option<SelfParam>,
     pub is_unsafe: bool,
     pub is_varargs: bool,
     pub visibility: RawVisibility,
@@ -42,7 +42,7 @@ impl FunctionData {
             params: func.params.to_vec(),
             ret_type: func.ret_type.clone(),
             attrs: item_tree.attrs(ModItem::from(loc.id.value).into()).clone(),
-            has_self_param: func.has_self_param,
+            self_param: func.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 a67e75dac..1eaea66e4 100644
--- a/crates/ra_hir_def/src/item_tree.rs
+++ b/crates/ra_hir_def/src/item_tree.rs
@@ -500,7 +500,7 @@ pub struct Function {
     pub name: Name,
     pub visibility: RawVisibilityId,
     pub generic_params: GenericParamsId,
-    pub has_self_param: bool,
+    pub self_param: Option<SelfParam>,
     pub is_unsafe: bool,
     pub params: Box<[TypeRef]>,
     pub is_varargs: bool,
@@ -508,6 +508,12 @@ pub struct Function {
     pub ast_id: FileAstId<ast::Fn>,
 }
 
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub struct SelfParam {
+    pub is_ref: bool,
+    pub is_mut: bool,
+}
+
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct Struct {
     pub name: Name,
diff --git a/crates/ra_hir_def/src/item_tree/lower.rs b/crates/ra_hir_def/src/item_tree/lower.rs
index 450ef8798..89ad91d37 100644
--- a/crates/ra_hir_def/src/item_tree/lower.rs
+++ b/crates/ra_hir_def/src/item_tree/lower.rs
@@ -283,7 +283,7 @@ impl Ctx {
         let name = func.name()?.as_name();
 
         let mut params = Vec::new();
-        let mut has_self_param = false;
+        let mut func_self_param = None;
         if let Some(param_list) = func.param_list() {
             if let Some(self_param) = param_list.self_param() {
                 let self_type = match self_param.ty() {
@@ -302,7 +302,10 @@ impl Ctx {
                     }
                 };
                 params.push(self_type);
-                has_self_param = true;
+                func_self_param = Some(SelfParam {
+                    is_ref: self_param.amp_token().is_some(),
+                    is_mut: self_param.mut_token().is_some(),
+                });
             }
             for param in param_list.params() {
                 let type_ref = TypeRef::from_ast_opt(&self.body_ctx, param.ty());
@@ -335,7 +338,7 @@ impl Ctx {
             name,
             visibility,
             generic_params: GenericParamsId::EMPTY,
-            has_self_param,
+            self_param: func_self_param,
             is_unsafe: func.unsafe_token().is_some(),
             params: params.into_boxed_slice(),
             is_varargs,