Make Chart.helpers importable (#4479)

Properly export helpers and remove dependencies to `Chart.helpers`. Helpers can now be accessed from `src/helpers/index.js` (`var helpers = require('path/to/helpers/index')`, instead of `var helpers = Chart.helpers`).

Author: simonbrunel

src/chart.js

@@ -3,11 +3,10 @@
  */
 var Chart = require('./core/core')();
 
-require('./helpers/helpers.core')(Chart);
-require('./helpers/helpers.easing')(Chart);
+Chart.helpers = require('./helpers/index');
+
+// @todo dispatch these helpers into appropriated helpers/helpers.* file and write unit tests!
 require('./core/core.helpers')(Chart);
-require('./helpers/helpers.time')(Chart);
-require('./helpers/helpers.canvas')(Chart);
 
 require('./platforms/platform')(Chart);
 require('./core/core.element')(Chart);
@@ -66,3 +65,14 @@ module.exports = Chart;
 if (typeof window !== 'undefined') {
 	window.Chart = Chart;
 }
+
+// DEPRECATIONS
+
+/**
+ * Provided for backward compatibility, use Chart.helpers.canvas instead.
+ * @namespace Chart.canvasHelpers
+ * @deprecated since version 2.6.0
+ * @todo remove at version 3
+ * @private
+ */
+Chart.canvasHelpers = Chart.helpers.canvas;

src/controllers/controller.bar.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	Chart.defaults.bar = {
 		hover: {

src/controllers/controller.bubble.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	Chart.defaults.bubble = {
 		hover: {

src/controllers/controller.doughnut.js

@@ -1,9 +1,10 @@
 'use strict';
 
+var helpers = require('../helpers/index');
+
 module.exports = function(Chart) {
 
-	var helpers = Chart.helpers,
-		defaults = Chart.defaults;
+	var defaults = Chart.defaults;
 
 	defaults.doughnut = {
 		animation: {

src/controllers/controller.line.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	Chart.defaults.line = {
 		showLines: true,
@@ -285,13 +285,13 @@ module.exports = function(Chart) {
 			var ilen = points.length;
 			var i = 0;
 
-			Chart.helpers.canvas.clipArea(chart.ctx, area);
+			helpers.canvas.clipArea(chart.ctx, area);
 
 			if (lineEnabled(me.getDataset(), chart.options)) {
 				meta.dataset.draw();
 			}
 
-			Chart.helpers.canvas.unclipArea(chart.ctx);
+			helpers.canvas.unclipArea(chart.ctx);
 
 			// Draw the points
 			for (; i<ilen; ++i) {

src/controllers/controller.polarArea.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	Chart.defaults.polarArea = {
 

src/controllers/controller.radar.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	Chart.defaults.radar = {
 		scale: {

src/core/core.animation.js

@@ -1,9 +1,9 @@
 /* global window: false */
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	Chart.defaults.global.animation = {
 		duration: 1000,

src/core/core.controller.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 	var plugins = Chart.plugins;
 	var platform = Chart.platform;
 

src/core/core.datasetController.js

@@ -1,8 +1,8 @@
 'use strict';
 
-module.exports = function(Chart) {
+var helpers = require('../helpers/index');
 
-	var helpers = Chart.helpers;
+module.exports = function(Chart) {
 
 	var arrayEvents = ['push', 'pop', 'shift', 'splice', 'unshift'];