From 835cfd2a15e9582c71d6baaf2f93bab9aee7b669 Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Tue, 14 Oct 2014 09:31:26 +1100
Subject: [PATCH] add hasSpread helper to spread transformer

---
 lib/6to5/transformers/spread.js | 57 ++++++++++++++++-----------------
 1 file changed, 28 insertions(+), 29 deletions(-)

diff --git a/lib/6to5/transformers/spread.js b/lib/6to5/transformers/spread.js
index 6dc2187112..0d9af43eb9 100644
--- a/lib/6to5/transformers/spread.js
+++ b/lib/6to5/transformers/spread.js
@@ -13,15 +13,15 @@ var getSpreadLiteral = function (spread, file) {
   return literal;
 };
 
+var hasSpread = function (nodes) {
+  return nodes.length && _.last(args).type === "SpreadElement";
+};
+
 exports.ArrayExpression = function (node, parent, file) {
   var elements = node.elements;
-  if (!elements.length) return;
+  if (!hasSpread(elements)) return;
 
   var spread = elements.pop();
-  if (spread.type !== "SpreadElement") {
-    elements.push(spread);
-    return;
-  }
 
   var concat = util.template("array-concat", {
     ARGUMENT: getSpreadLiteral(spread, file)
@@ -34,33 +34,32 @@ exports.ArrayExpression = function (node, parent, file) {
 
 exports.CallExpression = function (node, parent, file) {
   var args = node.arguments;
+  if (!hasSpread(args)) return;
 
-  if (args.length && _.last(args).type === "SpreadElement") {
-    var spread = args.pop();
+  var spread = args.pop();
 
-    var spreadLiteral  = getSpreadLiteral(spread, file);
-    var contextLiteral = b.literal(null);
+  var spreadLiteral  = getSpreadLiteral(spread, file);
+  var contextLiteral = b.literal(null);
 
-    node.arguments = [];
+  node.arguments = [];
 
-    if (args.length) {
-      var concat = util.template("array-concat");
-      concat.arguments = [spreadLiteral];
-      concat.callee.object.elements = args;
-      node.arguments.push(concat);
-    } else {
-      node.arguments.push(spreadLiteral);
-    }
-
-    var callee = node.callee;
-
-    if (callee.type === "MemberExpression") {
-      contextLiteral = callee.object;
-      callee.property = b.memberExpression(callee.property, b.identifier("apply"), false);
-    } else {
-      node.callee = b.memberExpression(node.callee, b.identifier("apply"), false);
-    }
-
-    node.arguments.unshift(contextLiteral);
+  if (args.length) {
+    var concat = util.template("array-concat");
+    concat.arguments = [spreadLiteral];
+    concat.callee.object.elements = args;
+    node.arguments.push(concat);
+  } else {
+    node.arguments.push(spreadLiteral);
   }
+
+  var callee = node.callee;
+
+  if (callee.type === "MemberExpression") {
+    contextLiteral = callee.object;
+    callee.property = b.memberExpression(callee.property, b.identifier("apply"), false);
+  } else {
+    node.callee = b.memberExpression(node.callee, b.identifier("apply"), false);
+  }
+
+  node.arguments.unshift(contextLiteral);
 };