Common logic for resolving line element options (#6005)

diff --git a/src/controllers/controller.line.js b/src/controllers/controller.line.js
index e57d5e2ffb24de2b1cbed410b56034260a13c0b4..5341ac1e6dd1d1966d1fbf5208449ad3c356789a 100644 (file)
--- a/src/controllers/controller.line.js
+++ b/src/controllers/controller.line.js
@@ -44,17 +44,13 @@ module.exports = DatasetController.extend({
                var meta = me.getMeta();
                var line = meta.dataset;
                var points = meta.data || [];
-               var options = me.chart.options;
-               var lineElementOptions = options.elements.line;
                var scale = me.getScaleForId(meta.yAxisID);
-               var i, ilen, custom;
                var dataset = me.getDataset();
-               var showLine = lineEnabled(dataset, options);
+               var showLine = lineEnabled(dataset, me.chart.options);
+               var i, ilen;
 
                // Update Line
                if (showLine) {
-                       custom = line.custom || {};
-
                        // Compatibility: If the properties are defined with only the old name, use those values
                        if ((dataset.tension !== undefined) && (dataset.lineTension === undefined)) {
                                dataset.lineTension = dataset.tension;
@@ -66,24 +62,7 @@ module.exports = DatasetController.extend({
                        // Data
                        line._children = points;
                        // Model
-                       line._model = {
-                               // Appearance
-                               // The default behavior of lines is to break at null values, according
-                               // to https://github.com/chartjs/Chart.js/issues/2435#issuecomment-216718158
-                               // This option gives lines the ability to span gaps
-                               spanGaps: valueOrDefault(dataset.spanGaps, options.spanGaps),
-                               tension: resolve([custom.tension, dataset.lineTension, lineElementOptions.tension]),
-                               backgroundColor: resolve([custom.backgroundColor, dataset.backgroundColor, lineElementOptions.backgroundColor]),
-                               borderWidth: resolve([custom.borderWidth, dataset.borderWidth, lineElementOptions.borderWidth]),
-                               borderColor: resolve([custom.borderColor, dataset.borderColor, lineElementOptions.borderColor]),
-                               borderCapStyle: resolve([custom.borderCapStyle, dataset.borderCapStyle, lineElementOptions.borderCapStyle]),
-                               borderDash: resolve([custom.borderDash, dataset.borderDash, lineElementOptions.borderDash]),
-                               borderDashOffset: resolve([custom.borderDashOffset, dataset.borderDashOffset, lineElementOptions.borderDashOffset]),
-                               borderJoinStyle: resolve([custom.borderJoinStyle, dataset.borderJoinStyle, lineElementOptions.borderJoinStyle]),
-                               fill: resolve([custom.fill, dataset.fill, lineElementOptions.fill]),
-                               steppedLine: resolve([custom.steppedLine, dataset.steppedLine, lineElementOptions.stepped]),
-                               cubicInterpolationMode: resolve([custom.cubicInterpolationMode, dataset.cubicInterpolationMode, lineElementOptions.cubicInterpolationMode]),
-                       };
+                       line._model = me._resolveLineOptions(line);
 
                        line.pivot();
                }
@@ -114,7 +93,7 @@ module.exports = DatasetController.extend({
                var xScale = me.getScaleForId(meta.xAxisID);
                var x, y;
 
-               var options = me._resolveElementOptions(point, index);
+               var options = me._resolvePointOptions(point, index);
 
                x = xScale.getPixelForValue(typeof value === 'object' ? value : NaN, index, datasetIndex);
                y = reset ? yScale.getBasePixel() : me.calculatePointY(value, index, datasetIndex);
@@ -148,12 +127,11 @@ module.exports = DatasetController.extend({
        /**
         * @private
         */
-       _resolveElementOptions: function(point, index) {
+       _resolvePointOptions: function(element, index) {
                var me = this;
                var chart = me.chart;
-               var datasets = chart.data.datasets;
-               var dataset = datasets[me.index];
-               var custom = point.custom || {};
+               var dataset = chart.data.datasets[me.index];
+               var custom = element.custom || {};
                var options = chart.options.elements.point;
                var values = {};
                var i, ilen, key;
@@ -194,6 +172,50 @@ module.exports = DatasetController.extend({
                return values;
        },
 
+       /**
+        * @private
+        */
+       _resolveLineOptions: function(element) {
+               var me = this;
+               var chart = me.chart;
+               var dataset = chart.data.datasets[me.index];
+               var custom = element.custom || {};
+               var options = chart.options;
+               var elementOptions = options.elements.line;
+               var values = {};
+               var i, ilen, key;
+
+               var keys = [
+                       'backgroundColor',
+                       'borderWidth',
+                       'borderColor',
+                       'borderCapStyle',
+                       'borderDash',
+                       'borderDashOffset',
+                       'borderJoinStyle',
+                       'fill',
+                       'cubicInterpolationMode'
+               ];
+
+               for (i = 0, ilen = keys.length; i < ilen; ++i) {
+                       key = keys[i];
+                       values[key] = resolve([
+                               custom[key],
+                               dataset[key],
+                               elementOptions[key]
+                       ]);
+               }
+
+               // The default behavior of lines is to break at null values, according
+               // to https://github.com/chartjs/Chart.js/issues/2435#issuecomment-216718158
+               // This option gives lines the ability to span gaps
+               values.spanGaps = valueOrDefault(dataset.spanGaps, options.spanGaps);
+               values.tension = resolve([custom.tension, dataset.lineTension, elementOptions.tension]);
+               values.steppedLine = resolve([custom.steppedLine, dataset.steppedLine, elementOptions.stepped]);
+
+               return values;
+       },
+
        calculatePointY: function(value, index, datasetIndex) {
                var me = this;
                var chart = me.chart;