use Array.isArray instead of _.isArray

lib/6to5/generation/buffer.js

@@ -123,7 +123,7 @@ Buffer.prototype.isLast = function (cha, trimRight) {
   if (trimRight) buf = util.trimRight(buf);
   var last = buf[buf.length - 1];
 
-  if (_.isArray(cha)) {
+  if (Array.isArray(cha)) {
     return _.contains(cha, last);
   } else {
     return cha === last;

lib/6to5/traverse/index.js

@@ -33,7 +33,7 @@ TraversalContext.prototype.maybeReplace = function (result, obj, key, node) {
   if (result === false) return node;
   if (result == null) return node;
 
-  var isArray = _.isArray(result);
+  var isArray = Array.isArray(result);
 
   // inherit comments from original node to the first replacement node
   var inheritTo = result;
@@ -96,7 +96,7 @@ function traverse(parent, opts, scope) {
   if (!parent) return;
 
   // array of nodes
-  if (_.isArray(parent)) {
+  if (Array.isArray(parent)) {
     for (var i = 0; i < parent.length; i++)
       traverse(parent[i], opts, scope);
     return;
@@ -114,7 +114,7 @@ function traverse(parent, opts, scope) {
     var nodes = parent[key];
     if (!nodes) continue;
 
-    if (_.isArray(nodes)) {
+    if (Array.isArray(nodes)) {
       for (var k = 0; k < nodes.length; k++) {
         context = new TraversalContext(context);
         context.visit(nodes, k, opts, scope, parent);

lib/6to5/types/index.js

@@ -320,7 +320,7 @@ t.toBlock = function (node, parent) {
     return node;
   }
 
-  if (!_.isArray(node)) {
+  if (!Array.isArray(node)) {
     if (!t.isStatement(node)) {
       if (t.isFunction(parent)) {
         node = t.returnStatement(node);

lib/6to5/util.js

@@ -39,7 +39,7 @@ exports.list = function (val) {
 
 exports.regexify = function (val) {
   if (!val) return new RegExp(/.^/);
-  if (_.isArray(val)) val = val.join("|");
+  if (Array.isArray(val)) val = val.join("|");
   if (_.isString(val)) return new RegExp(val);
   if (_.isRegExp(val)) return val;
   throw new TypeError("illegal type for regexify");
@@ -48,7 +48,7 @@ exports.regexify = function (val) {
 exports.arrayify = function (val) {
   if (!val) return [];
   if (_.isString(val)) return exports.list(val);
-  if (_.isArray(val)) return val;
+  if (Array.isArray(val)) return val;
   throw new TypeError("illegal type for arrayify");
 };