Cleanup and reorganize core and canvas helpers

Move some of the "core" and "canvas" utils in `helpers.core.js` and `helpers.canvas.js` and introduce the new `isNullOrUndef` and `isObject` helpers. Deprecate `indexOf` and rename `drawRoundedRectangle` to `roundedRect` which now creates a simple `rect` path if radius is 0. Write missing unit tests for the moved helpers.

.gitignore

@@ -4,6 +4,7 @@
 /dist
 /docs/index.md
 /gh-pages
+/jsdoc
 /node_modules
 .DS_Store
 .idea

src/chart.js

@@ -3,11 +3,12 @@
  */
 var Chart = require('./core/core.js')();
 
+require('./helpers/helpers.core')(Chart);
 require('./core/core.helpers')(Chart);
 require('./helpers/helpers.time')(Chart);
+require('./helpers/helpers.canvas')(Chart);
 
 require('./platforms/platform.js')(Chart);
-require('./core/core.canvasHelpers')(Chart);
 require('./core/core.element')(Chart);
 require('./core/core.plugin.js')(Chart);
 require('./core/core.animation')(Chart);

src/controllers/controller.line.js

@@ -285,13 +285,13 @@ module.exports = function(Chart) {
 			var ilen = points.length;
 			var i = 0;
 
-			Chart.canvasHelpers.clipArea(chart.ctx, area);
+			Chart.helpers.canvas.clipArea(chart.ctx, area);
 
 			if (lineEnabled(me.getDataset(), chart.options)) {
 				meta.dataset.draw();
 			}
 
-			Chart.canvasHelpers.unclipArea(chart.ctx);
+			Chart.helpers.canvas.unclipArea(chart.ctx);
 
 			// Draw the points
 			for (; i<ilen; ++i) {

src/core/core.controller.js

@@ -151,7 +151,7 @@ module.exports = function(Chart) {
 		},
 
 		clear: function() {
-			helpers.clear(this);
+			helpers.canvas.clear(this);
 			return this;
 		},
 
@@ -511,7 +511,7 @@ module.exports = function(Chart) {
 
 			me.clear();
 
-			if (easingValue === undefined || easingValue === null) {
+			if (helpers.isNullOrUndef(easingValue)) {
 				easingValue = 1;
 			}
 
@@ -688,7 +688,7 @@ module.exports = function(Chart) {
 
 			if (canvas) {
 				me.unbindEvents();
-				helpers.clear(me);
+				helpers.canvas.clear(me);
 				platform.releaseContext(me.ctx);
 				me.canvas = null;
 				me.ctx = null;

src/core/core.helpers.js

@@ -5,32 +5,9 @@
 var color = require('chartjs-color');
 
 module.exports = function(Chart) {
-	// Global Chart helpers object for utility methods and classes
-	var helpers = Chart.helpers = {};
+	var helpers = Chart.helpers;
 
 	// -- Basic js utility methods
-	helpers.each = function(loopable, callback, self, reverse) {
-		// Check to see if null or undefined firstly.
-		var i, len;
-		if (helpers.isArray(loopable)) {
-			len = loopable.length;
-			if (reverse) {
-				for (i = len - 1; i >= 0; i--) {
-					callback.call(self, loopable[i], i);
-				}
-			} else {
-				for (i = 0; i < len; i++) {
-					callback.call(self, loopable[i], i);
-				}
-			}
-		} else if (typeof loopable === 'object') {
-			var keys = Object.keys(loopable);
-			len = keys.length;
-			for (i = 0; i < len; i++) {
-				callback.call(self, loopable[keys[i]], keys[i]);
-			}
-		}
-	};
 	helpers.clone = function(obj) {
 		var objClone = {};
 		helpers.each(obj, function(value, key) {
@@ -123,32 +100,7 @@ module.exports = function(Chart) {
 
 		return base;
 	};
-	helpers.getValueAtIndexOrDefault = function(value, index, defaultValue) {
-		if (value === undefined || value === null) {
-			return defaultValue;
-		}
-
-		if (helpers.isArray(value)) {
-			return index < value.length ? value[index] : defaultValue;
-		}
 
-		return value;
-	};
-	helpers.getValueOrDefault = function(value, defaultValue) {
-		return value === undefined ? defaultValue : value;
-	};
-	helpers.indexOf = Array.prototype.indexOf?
-		function(array, item) {
-			return array.indexOf(item);
-		}:
-		function(array, item) {
-			for (var i = 0, ilen = array.length; i < ilen; ++i) {
-				if (array[i] === item) {
-					return i;
-				}
-			}
-			return -1;
-		};
 	helpers.where = function(collection, filterCallback) {
 		if (helpers.isArray(collection) && Array.prototype.filter) {
 			return collection.filter(filterCallback);
@@ -178,7 +130,7 @@ module.exports = function(Chart) {
 		};
 	helpers.findNextWhere = function(arrayToSearch, filterCallback, startIndex) {
 		// Default to start of the array
-		if (startIndex === undefined || startIndex === null) {
+		if (helpers.isNullOrUndef(startIndex)) {
 			startIndex = -1;
 		}
 		for (var i = startIndex + 1; i < arrayToSearch.length; i++) {
@@ -190,7 +142,7 @@ module.exports = function(Chart) {
 	};
 	helpers.findPreviousWhere = function(arrayToSearch, filterCallback, startIndex) {
 		// Default to end of the array
-		if (startIndex === undefined || startIndex === null) {
+		if (helpers.isNullOrUndef(startIndex)) {
 			startIndex = arrayToSearch.length;
 		}
 		for (var i = startIndex - 1; i >= 0; i--) {
@@ -223,13 +175,6 @@ module.exports = function(Chart) {
 
 		return ChartElement;
 	};
-	helpers.noop = function() {};
-	helpers.uid = (function() {
-		var id = 0;
-		return function() {
-			return id++;
-		};
-	}());
 	// -- Math methods
 	helpers.isNumber = function(n) {
 		return !isNaN(parseFloat(n)) && isFinite(n);
@@ -837,9 +782,6 @@ module.exports = function(Chart) {
 		canvas.style.width = width + 'px';
 	};
 	// -- Canvas methods
-	helpers.clear = function(chart) {
-		chart.ctx.clearRect(0, 0, chart.width, chart.height);
-	};
 	helpers.fontString = function(pixelSize, fontStyle, fontFamily) {
 		return fontStyle + ' ' + pixelSize + 'px ' + fontFamily;
 	};
@@ -903,19 +845,6 @@ module.exports = function(Chart) {
 		});
 		return numberOfLines;
 	};
-	helpers.drawRoundedRectangle = function(ctx, x, y, width, height, radius) {
-		ctx.beginPath();
-		ctx.moveTo(x + radius, y);
-		ctx.lineTo(x + width - radius, y);
-		ctx.quadraticCurveTo(x + width, y, x + width, y + radius);
-		ctx.lineTo(x + width, y + height - radius);
-		ctx.quadraticCurveTo(x + width, y + height, x + width - radius, y + height);
-		ctx.lineTo(x + radius, y + height);
-		ctx.quadraticCurveTo(x, y + height, x, y + height - radius);
-		ctx.lineTo(x, y + radius);
-		ctx.quadraticCurveTo(x, y, x + radius, y);
-		ctx.closePath();
-	};
 
 	helpers.color = !color?
 		function(value) {
@@ -931,54 +860,10 @@ module.exports = function(Chart) {
 			return color(value);
 		};
 
-	helpers.isArray = Array.isArray?
-		function(obj) {
-			return Array.isArray(obj);
-		} :
-		function(obj) {
-			return Object.prototype.toString.call(obj) === '[object Array]';
-		};
-	// ! @see http://stackoverflow.com/a/14853974
-	helpers.arrayEquals = function(a0, a1) {
-		var i, ilen, v0, v1;
-
-		if (!a0 || !a1 || a0.length !== a1.length) {
-			return false;
-		}
-
-		for (i = 0, ilen=a0.length; i < ilen; ++i) {
-			v0 = a0[i];
-			v1 = a1[i];
-
-			if (v0 instanceof Array && v1 instanceof Array) {
-				if (!helpers.arrayEquals(v0, v1)) {
-					return false;
-				}
-			} else if (v0 !== v1) {
-				// NOTE: two different object instances will never be equal: {x:20} != {x:20}
-				return false;
-			}
-		}
-
-		return true;
-	};
-	helpers.callback = function(fn, args, thisArg) {
-		if (fn && typeof fn.call === 'function') {
-			return fn.apply(thisArg, args);
-		}
-	};
 	helpers.getHoverColor = function(colorValue) {
 		/* global CanvasPattern */
 		return (colorValue instanceof CanvasPattern) ?
 			colorValue :
 			helpers.color(colorValue).saturate(0.5).darken(0.1).rgbString();
 	};
-
-	/**
-	 * Provided for backward compatibility, use Chart.helpers#callback instead.
-	 * @function Chart.helpers#callCallback
-	 * @deprecated since version 2.6.0
-	 * @todo remove at version 3
-	 */
-	helpers.callCallback = helpers.callback;
 };

src/core/core.scale.js

@@ -422,7 +422,7 @@ module.exports = function(Chart) {
 		// Get the correct value. NaN bad inputs, If the value type is object get the x or y based on whether we are horizontal or not
 		getRightValue: function(rawValue) {
 			// Null and undefined values first
-			if (rawValue === null || typeof(rawValue) === 'undefined') {
+			if (helpers.isNullOrUndef(rawValue)) {
 				return NaN;
 			}
 			// isNaN(object) returns true, so make sure NaN is checking for a number; Discard Infinite values
@@ -575,15 +575,15 @@ module.exports = function(Chart) {
 			helpers.each(me.ticks, function(tick, index) {
 				var label = (tick && tick.value) || tick;
 				// If the callback returned a null or undefined value, do not draw this line
-				if (label === undefined || label === null) {
+				if (helpers.isNullOrUndef(label)) {
 					return;
 				}
 
 				var isLastTick = me.ticks.length === index + 1;
 
 				// Since we always show the last tick,we need may need to hide the last shown one before
 				var shouldSkip = (skipRatio > 1 && index % skipRatio > 0) || (index % skipRatio === 0 && index + skipRatio >= me.ticks.length);
-				if (shouldSkip && !isLastTick || (label === undefined || label === null)) {
+				if (shouldSkip && !isLastTick || helpers.isNullOrUndef(label)) {
 					return;
 				}
 

src/elements/element.point.js

@@ -94,7 +94,7 @@ module.exports = function(Chart) {
 				ctx.fillStyle = color(ctx.fillStyle).alpha(ratio).rgbString();
 			}
 
-			Chart.canvasHelpers.drawPoint(ctx, pointStyle, radius, x, y);
+			Chart.helpers.canvas.drawPoint(ctx, pointStyle, radius, x, y);
 		}
 	});
 };