Fix conflict

c3.js

@@ -1630,11 +1630,11 @@
     };
     c3_chart_internal_fn.isOrderDesc = function () {
         var config = this.config;
-        return config.data_order && config.data_order.toLowerCase() === 'desc';
+        return typeof(config.data_order) === 'string' && config.data_order.toLowerCase() === 'desc';
     };
     c3_chart_internal_fn.isOrderAsc = function () {
         var config = this.config;
-        return config.data_order && config.data_order.toLowerCase() === 'asc';
+        return typeof(config.data_order) === 'string' && config.data_order.toLowerCase() === 'asc';
     };
     c3_chart_internal_fn.orderTargets = function (targets) {
         var $$ = this, config = $$.config, orderAsc = $$.isOrderAsc(), orderDesc = $$.isOrderDesc();

spec/data-spec.js

+var describe = window.describe,
+    expect = window.expect,
+    it = window.it,
+    beforeEach = window.beforeEach;
+
+describe('c3 chart data', function () {
+    'use strict';
+
+    var chart, d3;
+
+    beforeEach(function () {
+        window.initDom();
+        chart = window.c3.generate({
+            data: {
+                columns: [
+                    ['data1', 30, 200, 100, 400, 150, 250],
+                    ['data2', 50, 20, 10, 40, 15, 25],
+                    ['data3', 150, 120, 110, 140, 115, 125]
+                ],
+                order: function () {
+                    return 0;
+                }
+            }
+        });
+        d3 = chart.internal.d3;
+    });
+
+    describe('function in data.order', function () {
+        it('should return false in isOrderAsc and isOrderDesc functions', function () {
+            expect(chart.internal.isOrderAsc() || chart.internal.isOrderDesc()).toBe(false);
+        });
+    });
+});

src/data.js

@@ -206,11 +206,11 @@ c3_chart_internal_fn.hasPositiveValueInTargets = function (targets) {
 };
 c3_chart_internal_fn.isOrderDesc = function () {
     var config = this.config;
-    return config.data_order && config.data_order.toLowerCase() === 'desc';
+    return typeof(config.data_order) === 'string' && config.data_order.toLowerCase() === 'desc';
 };
 c3_chart_internal_fn.isOrderAsc = function () {
     var config = this.config;
-    return config.data_order && config.data_order.toLowerCase() === 'asc';
+    return typeof(config.data_order) === 'string' && config.data_order.toLowerCase() === 'asc';
 };
 c3_chart_internal_fn.orderTargets = function (targets) {
     var $$ = this, config = $$.config, orderAsc = $$.isOrderAsc(), orderDesc = $$.isOrderDesc();