Fix tooltip error and add fixed steps to linear scale

.gitignore

@@ -9,3 +9,5 @@ docs/index.md
 bower_components/
 
 coverage/*
+
+nbproject/*

Chart.js

@@ -97,6 +97,11 @@
 			},
 			onClick: null,
 			defaultColor: 'rgba(0,0,0,0.1)',
+			defaultFontColor: '#666',
+			defaultFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
+			defaultFontSize: 12,
+			defaultFontStyle: 'normal',
+			showLines: true,
 
 			// Element defaults defined in element extensions
 			elements: {},
@@ -180,7 +185,7 @@
 	helpers.extend = function(base) {
 		var len = arguments.length;
 		var additionalArgs = [];
-		for(var i = 1; i < len; i++) {
+		for (var i = 1; i < len; i++) {
 			additionalArgs.push(arguments[i]);
 		}
 		helpers.each(additionalArgs, function(extensionObject) {
@@ -314,7 +319,8 @@
 			return arrayToSearch.indexOf(item);
 		} else {
 			for (var i = 0; i < arrayToSearch.length; i++) {
-				if (arrayToSearch[i] === item) return i;
+				if (arrayToSearch[i] === item)
+					return i;
 			}
 			return -1;
 		}
@@ -394,6 +400,9 @@
 	helpers.isNumber = function(n) {
 		return !isNaN(parseFloat(n)) && isFinite(n);
 	};
+	helpers.almostEquals = function(x, y, epsilon) {
+		return Math.abs(x - y) < epsilon;
+	};
 	helpers.max = function(array) {
 		return array.reduce(function(max, value) {
 			if (!isNaN(value)) {
@@ -803,7 +812,8 @@
 	};
 	helpers.bindEvents = function(chartInstance, arrayOfEvents, handler) {
 		// Create the events object if it's not already present
-		if (!chartInstance.events) chartInstance.events = {};
+		if (!chartInstance.events)
+			chartInstance.events = {};
 
 		helpers.each(arrayOfEvents, function(eventName) {
 			chartInstance.events[eventName] = function() {
@@ -978,7 +988,6 @@
 		// Insert the iframe so that contentWindow is available
 		node.insertBefore(hiddenIframe, node.firstChild);
 
-		var timer = 0;
 		(hiddenIframe.contentWindow || hiddenIframe).onresize = function() {
 			if (callback) {
 				callback();
@@ -999,6 +1008,17 @@
 		}
 		return Array.isArray(obj);
 	};
+	helpers.pushAllIfDefined = function(element, array) {
+		if (typeof element == "undefined") {
+			return;
+		}
+
+		if (helpers.isArray(element)) {
+			array.push.apply(array, element);
+		} else {
+			array.push(element);
+		}
+	};
 	helpers.isDatasetVisible = function(dataset) {
 		return !dataset.hidden;
 	};
@@ -2223,10 +2243,10 @@
 
 		labels: {
 			boxWidth: 40,
-			fontSize: 12,
-			fontStyle: "normal",
-			fontColor: "#666",
-			fontFamily: "Helvetica Neue",
+			fontSize: Chart.defaults.global.defaultFontSize,
+			fontStyle: Chart.defaults.global.defaultFontStyle,
+			fontColor: Chart.defaults.global.defaultFontColor,
+			fontFamily: Chart.defaults.global.defaultFontFamily,
 			padding: 10,
 			// Generates labels shown in the legend
 			// Valid properties to return:
@@ -2549,10 +2569,10 @@
 
 		// scale label
 		scaleLabel: {
-			fontColor: '#666',
-			fontFamily: 'Helvetica Neue',
-			fontSize: 12,
-			fontStyle: 'normal',
+			fontColor: Chart.defaults.global.defaultFontColor,
+			fontFamily: Chart.defaults.global.defaultFontFamily,
+			fontSize: Chart.defaults.global.defaultFontSize,
+			fontStyle: Chart.defaults.global.defaultFontStyle,
 
 			// actual label
 			labelString: '',
@@ -2564,10 +2584,10 @@
 		// label settings
 		ticks: {
 			beginAtZero: false,
-			fontSize: 12,
-			fontStyle: "normal",
-			fontColor: "#666",
-			fontFamily: "Helvetica Neue",
+			fontSize: Chart.defaults.global.defaultFontSize,
+			fontStyle: Chart.defaults.global.defaultFontStyle,
+			fontColor: Chart.defaults.global.defaultFontColor,
+			fontFamily: Chart.defaults.global.defaultFontFamily,
 			maxRotation: 90,
 			mirror: false,
 			padding: 10,
@@ -3248,9 +3268,9 @@
 		position: 'top',
 		fullWidth: true, // marks that this box should take the full width of the canvas (pushing down other boxes)
 
-		fontColor: '#666',
-		fontFamily: 'Helvetica Neue',
-		fontSize: 12,
+		fontColor: Chart.defaults.global.defaultFontColor,
+		fontFamily: Chart.defaults.global.defaultFontFamily,
+		fontSize: Chart.defaults.global.defaultFontSize,
 		fontStyle: 'bold',
 		padding: 10,
 
@@ -3445,21 +3465,21 @@
 		custom: null,
 		mode: 'single',
 		backgroundColor: "rgba(0,0,0,0.8)",
-		titleFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
-		titleFontSize: 12,
+		titleFontFamily: Chart.defaults.global.defaultFontFamily,
+		titleFontSize: Chart.defaults.global.defaultFontSize,
 		titleFontStyle: "bold",
 		titleSpacing: 2,
 		titleMarginBottom: 6,
 		titleColor: "#fff",
 		titleAlign: "left",
-		bodyFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
-		bodyFontSize: 12,
-		bodyFontStyle: "normal",
+		bodyFontFamily: Chart.defaults.global.defaultFontFamily,
+		bodyFontSize: Chart.defaults.global.defaultFontSize,
+		bodyFontStyle: Chart.defaults.global.defaultFontStyle,
 		bodySpacing: 2,
 		bodyColor: "#fff",
 		bodyAlign: "left",
-		footerFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
-		footerFontSize: 12,
+		footerFontFamily: Chart.defaults.global.defaultFontFamily,
+		footerFontSize: Chart.defaults.global.defaultFontSize,
 		footerFontStyle: "bold",
 		footerSpacing: 2,
 		footerMarginTop: 6,
@@ -3594,11 +3614,9 @@
 			var lines = [];
 
 			helpers.each(tooltipItems, function(bodyItem) {
-				var beforeLabel = this._options.tooltips.callbacks.beforeLabel.call(this, bodyItem, data) || '';
-				var bodyLabel = this._options.tooltips.callbacks.label.call(this, bodyItem, data) || '';
-				var afterLabel = this._options.tooltips.callbacks.afterLabel.call(this, bodyItem, data) || '';
-
-				lines.push(beforeLabel + bodyLabel + afterLabel);
+                helpers.pushAllIfDefined(this._options.tooltips.callbacks.beforeLabel.call(this, bodyItem, data), lines);
+                helpers.pushAllIfDefined(this._options.tooltips.callbacks.label.call(this, bodyItem, data), lines);
+                helpers.pushAllIfDefined(this._options.tooltips.callbacks.afterLabel.call(this, bodyItem, data), lines);
 			}, this);
 
 			return lines;
@@ -5722,11 +5740,11 @@
 
 			if (this.isHorizontal()) {
 				maxTicks = Math.min(this.options.ticks.maxTicksLimit ? this.options.ticks.maxTicksLimit : 11,
-				                    Math.ceil(this.width / 50));
+					Math.ceil(this.width / 50));
 			} else {
 				// The factor of 2 used to scale the font size has been experimentally determined.
 				maxTicks = Math.min(this.options.ticks.maxTicksLimit ? this.options.ticks.maxTicksLimit : 11,
-				                    Math.ceil(this.height / (2 * this.options.ticks.fontSize)));
+					Math.ceil(this.height / (2 * this.options.ticks.fontSize)));
 			}
 
 			// Make sure we always have at least 2 ticks 
@@ -5736,12 +5754,24 @@
 			// "nice number" algorithm. See http://stackoverflow.com/questions/8506881/nice-label-algorithm-for-charts-with-minimum-ticks
 			// for details.
 
-			var niceRange = helpers.niceNum(this.max - this.min, false);
-			var spacing = helpers.niceNum(niceRange / (maxTicks - 1), true);
+			var spacing;
+			var fixedStepSizeSet = this.options.ticks.fixedStepSize && this.options.ticks.fixedStepSize > 0;
+			if (fixedStepSizeSet) {
+				spacing = this.options.ticks.fixedStepSize;
+			} else {
+				var niceRange = helpers.niceNum(this.max - this.min, false);
+				spacing = helpers.niceNum(niceRange / (maxTicks - 1), true);
+			}
 			var niceMin = Math.floor(this.min / spacing) * spacing;
 			var niceMax = Math.ceil(this.max / spacing) * spacing;
+			var numSpaces = (niceMax - niceMin) / spacing;
 
-			var numSpaces = Math.ceil((niceMax - niceMin) / spacing);
+			// If very close to our rounded value, use it. 
+			if (helpers.almostEquals(numSpaces, Math.round(numSpaces), spacing / 1000)) {
+				numSpaces = Math.round(numSpaces);
+			} else {
+				numSpaces = Math.ceil(numSpaces);
+			}
 
 			// Put the values into the ticks array
 			this.ticks.push(this.options.ticks.min !== undefined ? this.options.ticks.min : niceMin);
@@ -5773,11 +5803,9 @@
 			this.ticksAsNumbers = this.ticks.slice(); // do after we potentially reverse the ticks
 			this.zeroLineIndex = this.ticks.indexOf(0);
 		},
-
 		getLabelForIndex: function(index, datasetIndex) {
 			return +this.getRightValue(this.chart.data.datasets[datasetIndex].data[index]);
 		},
-
 		// Utils
 		getPixelForValue: function(value, index, datasetIndex, includeOffset) {
 			// This must be called after fit has been run so that 
@@ -6036,16 +6064,16 @@
 
 		pointLabels: {
 			//String - Point label font declaration
-			fontFamily: "'Arial'",
+			fontFamily: Chart.defaults.global.defaultFontFamily,
 
 			//String - Point label font weight
-			fontStyle: "normal",
+			fontStyle: Chart.defaults.global.defaultFontStyle,
 
 			//Number - Point label font size in pixels
 			fontSize: 10,
 
 			//String - Point label font colour
-			fontColor: "#666",
+			fontColor: Chart.defaults.global.defaultFontColor,
 
 			//Function - Used to convert point labels
 			callback: function(label) {

docs/01-Scales.md

@@ -130,7 +130,13 @@ The linear scale extends the core scale class with the following tick template:
 }
 ```
 
-### Logarithmic Scale
+It also provides additional configuration options:
+
+Name | Type | Default | Description
+--- |:---:| --- | ---
+*ticks*.fixedStepSize | Number | - | User defined fixed step size for the scale. If set, the scale ticks will be enumerated by multiple of fixedStepSize, having one tick per increment. If not set, the ticks are labeled automatically using the nice numbers algorithm.
+
+#### Logarithmic Scale
 The logarithmic scale is used to display logarithmic data of course. It can be placed on either the x or y axis.
 
 The log scale extends the core scale class with the following tick template:

package.json

@@ -10,7 +10,7 @@
   },
   "devDependencies": {
     "color": "git://github.com/chartjs/color",
-    "gulp": "3.5.x",
+    "gulp": "3.9.x",
     "gulp-concat": "~2.1.x",
     "gulp-connect": "~2.0.5",
     "gulp-html-validator": "^0.0.2",

src/core/core.helpers.js

@@ -50,7 +50,7 @@
 	helpers.extend = function(base) {
 		var len = arguments.length;
 		var additionalArgs = [];
-		for(var i = 1; i < len; i++) {
+		for (var i = 1; i < len; i++) {
 			additionalArgs.push(arguments[i]);
 		}
 		helpers.each(additionalArgs, function(extensionObject) {
@@ -184,7 +184,8 @@
 			return arrayToSearch.indexOf(item);
 		} else {
 			for (var i = 0; i < arrayToSearch.length; i++) {
-				if (arrayToSearch[i] === item) return i;
+				if (arrayToSearch[i] === item)
+					return i;
 			}
 			return -1;
 		}
@@ -676,7 +677,8 @@
 	};
 	helpers.bindEvents = function(chartInstance, arrayOfEvents, handler) {
 		// Create the events object if it's not already present
-		if (!chartInstance.events) chartInstance.events = {};
+		if (!chartInstance.events)
+			chartInstance.events = {};
 
 		helpers.each(arrayOfEvents, function(eventName) {
 			chartInstance.events[eventName] = function() {
@@ -851,7 +853,6 @@
 		// Insert the iframe so that contentWindow is available
 		node.insertBefore(hiddenIframe, node.firstChild);
 
-		var timer = 0;
 		(hiddenIframe.contentWindow || hiddenIframe).onresize = function() {
 			if (callback) {
 				callback();
@@ -872,6 +873,17 @@
 		}
 		return Array.isArray(obj);
 	};
+	helpers.pushAllIfDefined = function(element, array) {
+		if (typeof element == "undefined") {
+			return;
+		}
+
+		if (helpers.isArray(element)) {
+			array.push.apply(array, element);
+		} else {
+			array.push(element);
+		}
+	};
 	helpers.isDatasetVisible = function(dataset) {
 		return !dataset.hidden;
 	};

src/core/core.tooltip.js

@@ -160,11 +160,9 @@
 			var lines = [];
 
 			helpers.each(tooltipItems, function(bodyItem) {
-				var beforeLabel = this._options.tooltips.callbacks.beforeLabel.call(this, bodyItem, data) || '';
-				var bodyLabel = this._options.tooltips.callbacks.label.call(this, bodyItem, data) || '';
-				var afterLabel = this._options.tooltips.callbacks.afterLabel.call(this, bodyItem, data) || '';
-
-				lines.push(beforeLabel + bodyLabel + afterLabel);
+                helpers.pushAllIfDefined(this._options.tooltips.callbacks.beforeLabel.call(this, bodyItem, data), lines);
+                helpers.pushAllIfDefined(this._options.tooltips.callbacks.label.call(this, bodyItem, data), lines);
+                helpers.pushAllIfDefined(this._options.tooltips.callbacks.afterLabel.call(this, bodyItem, data), lines);
 			}, this);
 
 			return lines;