4 files changed, 44 insertions, 11 deletions

diff --git a/crates/libeditor/src/scope/fn_scope.rs b/crates/libeditor/src/scope/fn_scope.rs
index abc8d34e7..60b8ce919 100644
--- a/crates/libeditor/src/scope/fn_scope.rs
+++ b/crates/libeditor/src/scope/fn_scope.rs
@@ -5,7 +5,7 @@ use std::{
 
 use libsyntax2::{
     SyntaxNodeRef, SyntaxNode, SmolStr, AstNode,
-    ast::{self, NameOwner, LoopBodyOwner},
+    ast::{self, NameOwner, LoopBodyOwner, ArgListOwner},
     algo::{ancestors, generate, walk::preorder}
 };
 
@@ -184,10 +184,10 @@ fn compute_expr_scopes(expr: ast::Expr, scopes: &mut FnScopes, scope: ScopeId) {
             }
         }
         ast::Expr::CallExpr(e) => {
-            e.arg_list().into_iter()
-                .flat_map(|it| it.args())
-                .chain(e.expr())
-                .for_each(|expr| compute_expr_scopes(expr, scopes, scope));
+            compute_call_scopes(e.expr(), e.arg_list(), scopes, scope);
+        }
+        ast::Expr::MethodCallExpr(e) => {
+            compute_call_scopes(e.expr(), e.arg_list(), scopes, scope);
         }
         ast::Expr::MatchExpr(e) => {
             if let Some(expr) = e.expr() {
@@ -210,6 +210,17 @@ fn compute_expr_scopes(expr: ast::Expr, scopes: &mut FnScopes, scope: ScopeId) {
         }
     };
 
+    fn compute_call_scopes(
+        receiver: Option<ast::Expr>,
+        arg_list: Option<ast::ArgList>,
+        scopes: &mut FnScopes, scope: ScopeId,
+    ) {
+        arg_list.into_iter()
+            .flat_map(|it| it.args())
+            .chain(receiver)
+            .for_each(|expr| compute_expr_scopes(expr, scopes, scope));
+    }
+
     fn compute_cond_scopes(cond: ast::Condition, scopes: &mut FnScopes, scope: ScopeId) -> Option<ScopeId> {
         if let Some(expr) = cond.expr() {
             compute_expr_scopes(expr, scopes, scope);
@@ -280,6 +291,16 @@ mod tests {
     }
 
     #[test]
+    fn test_metod_call_scope() {
+        do_check(r"
+            fn quux() {
+                z.f(|x| <|> );
+            }",
+            &["x"],
+        );
+    }
+
+    #[test]
     fn test_loop_scope() {
         do_check(r"
             fn quux() {
diff --git a/crates/libsyntax2/src/ast/generated.rs b/crates/libsyntax2/src/ast/generated.rs
index bdee635ae..11306a835 100644
--- a/crates/libsyntax2/src/ast/generated.rs
+++ b/crates/libsyntax2/src/ast/generated.rs
@@ -200,12 +200,10 @@ impl<'a> AstNode<'a> for CallExpr<'a> {
     fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
 }
 
+impl<'a> ast::ArgListOwner<'a> for CallExpr<'a> {}
 impl<'a> CallExpr<'a> {pub fn expr(self) -> Option<Expr<'a>> {
         super::child_opt(self)
     }
-pub fn arg_list(self) -> Option<ArgList<'a>> {
-        super::child_opt(self)
-    }
 }
 
 // CastExpr
@@ -934,7 +932,11 @@ impl<'a> AstNode<'a> for MethodCallExpr<'a> {
     fn syntax(self) -> SyntaxNodeRef<'a> { self.syntax }
 }
 
-impl<'a> MethodCallExpr<'a> {}
+impl<'a> ast::ArgListOwner<'a> for MethodCallExpr<'a> {}
+impl<'a> MethodCallExpr<'a> {pub fn expr(self) -> Option<Expr<'a>> {
+        super::child_opt(self)
+    }
+}
 
 // Module
 #[derive(Debug, Clone, Copy)]
diff --git a/crates/libsyntax2/src/ast/mod.rs b/crates/libsyntax2/src/ast/mod.rs
index 49e283f5e..274996171 100644
--- a/crates/libsyntax2/src/ast/mod.rs
+++ b/crates/libsyntax2/src/ast/mod.rs
@@ -26,6 +26,12 @@ pub trait LoopBodyOwner<'a>: AstNode<'a> {
     }
 }
 
+pub trait ArgListOwner<'a>: AstNode<'a> {
+    fn arg_list(self) -> Option<ArgList<'a>> {
+        child_opt(self)
+    }
+}
+
 pub trait TypeParamsOwner<'a>: AstNode<'a> {
     fn type_param_list(self) -> Option<TypeParamList<'a>> {
         child_opt(self)
diff --git a/crates/libsyntax2/src/grammar.ron b/crates/libsyntax2/src/grammar.ron
index 798725f7e..683623a5d 100644
--- a/crates/libsyntax2/src/grammar.ron
+++ b/crates/libsyntax2/src/grammar.ron
@@ -388,10 +388,14 @@ Grammar(
         "NamedFieldList": (),
         "NamedField": (),
         "CallExpr": (
-            options: [ "Expr", "ArgList" ]
+            traits: ["ArgListOwner"],
+            options: [ "Expr" ],
+        ),
+        "MethodCallExpr": (
+            traits: ["ArgListOwner"],
+            options: [ "Expr" ],
         ),
         "IndexExpr": (),
-        "MethodCallExpr": (),
         "FieldExpr": (),
         "TryExpr": (),
         "CastExpr": (),