Fix interpolate when data id is a string that can be converted to a color - #604

c3.js

@@ -4608,7 +4608,11 @@
                 }
                 interpolate = d3.interpolate(this._current, updated);
                 this._current = interpolate(0);
-                return function (t) { return $$.getArc(interpolate(t), true); };
+                return function (t) {
+                    var interpolated = interpolate(t);
+                    interpolated.data = d.data; // data.id will be updated by interporator
+                    return $$.getArc(interpolated, true);
+                };
             })
             .attr("transform", withTransform ? "scale(1)" : "")
             .style("fill", function (d) {

spec/arc-spec.js

+var describe = window.describe,
+    expect = window.expect,
+    it = window.it,
+    beforeEach = window.beforeEach;
+
+describe('c3 chart axis', function () {
+    'use strict';
+
+    var chart, d3, args;
+
+    beforeEach(function (done) {
+        if (typeof chart === 'undefined') {
+            window.initDom();
+        }
+        chart = window.c3.generate(args);
+        d3 = chart.internal.d3;
+        chart.internal.d3.select('.jasmine_html-reporter')
+            .style('position', 'absolute')
+            .style('right', 0);
+
+        window.setTimeout(function () {
+            done();
+        }, 10);
+    });
+
+    describe('show pie chart', function () {
+
+        args = {
+            data: {
+                columns: [
+                    ['data1', 30],
+                    ['data2', 150],
+                    ['data3', 120]
+                ],
+                type: 'pie'
+            }
+        };
+
+        it('should have correct classes', function () {
+            var chartArc = d3.select('.c3-chart-arcs'),
+            arcs = {
+                data1: chartArc.select('.c3-chart-arc.c3-target.c3-target-data1')
+                    .select('g.c3-shapes.c3-shapes-data1.c3-arcs.c3-arcs-data1')
+                    .select('path.c3-shape.c3-shape.c3-arc.c3-arc-data1'),
+                data2: chartArc.select('.c3-chart-arc.c3-target.c3-target-data2')
+                    .select('g.c3-shapes.c3-shapes-data2.c3-arcs.c3-arcs-data2')
+                    .select('path.c3-shape.c3-shape.c3-arc.c3-arc-data2'),
+                data3: chartArc.select('.c3-chart-arc.c3-target.c3-target-data3')
+                    .select('g.c3-shapes.c3-shapes-data3.c3-arcs.c3-arcs-data3')
+                    .select('path.c3-shape.c3-shape.c3-arc.c3-arc-data3')
+            };
+            expect(arcs.data1.size()).toBe(1);
+            expect(arcs.data2.size()).toBe(1);
+            expect(arcs.data3.size()).toBe(1);
+        });
+
+        it('should have correct d', function () {
+            expect(d3.select('.c3-arc-data1').attr('d')).toMatch(/M-124\..+,-171\..+A211\..+,211\..+ 0 0,1 -3\..+,-211\..+L0,0Z/);
+            expect(d3.select('.c3-arc-data2').attr('d')).toMatch(/M1\..+,-211\..+A211\..+,211\..+ 0 0,1 1\..+,211\..+L0,0Z/);
+            expect(d3.select('.c3-arc-data3').attr('d')).toMatch(/M1\..+,211\..+A211\..+,211\..+ 0 0,1 -124\..+,-171\..+L0,0Z/);
+        });
+
+        it('should set args with data id that can be converted to a color', function () {
+            args.data.columns = [
+                ['black', 30],
+                ['data2', 150],
+                ['data3', 120]
+            ];
+            expect(true).toBeTruthy();
+        });
+
+        it('should have correct d even if data id can be converted to a color', function () {
+            expect(d3.select('.c3-arc-black').attr('d')).toMatch(/M-124\..+,-171\..+A211\..+,211\..+ 0 0,1 -3\..+,-211\..+L0,0Z/);
+        });
+
+    });
+
+});

src/arc.js

@@ -311,7 +311,11 @@ c3_chart_internal_fn.redrawArc = function (duration, durationForExit, withTransf
             }
             interpolate = d3.interpolate(this._current, updated);
             this._current = interpolate(0);
-            return function (t) { return $$.getArc(interpolate(t), true); };
+            return function (t) {
+                var interpolated = interpolate(t);
+                interpolated.data = d.data; // data.id will be updated by interporator
+                return $$.getArc(interpolated, true);
+            };
         })
         .attr("transform", withTransform ? "scale(1)" : "")
         .style("fill", function (d) {