use some spreads

src/babel/transformation/helpers/replace-supers.js

@@ -295,7 +295,7 @@ export default class ReplaceSupers {
       } else {
         return t.callExpression(
           t.memberExpression(superProperty, t.identifier("call")),
-          [thisReference].concat(args)
+          [thisReference, ...args]
         );
       }
     } else {

src/babel/transformation/transformers/playground/method-binding.js

@@ -11,7 +11,7 @@ exports.BindMemberExpression = function (node, parent, scope) {
 
   var call = t.callExpression(
     t.memberExpression(t.memberExpression(object, prop), t.identifier("bind")),
-    [object].concat(node.arguments)
+    [object, ...node.arguments]
   );
 
   if (temp) {

src/babel/traversal/scope.js

@@ -1,5 +1,3 @@
-
-
 var includes = require("lodash/collection/includes");
 var traverse = require("./index");
 var defaults = require("lodash/object/defaults");