From bf191648790425345be8531115d88a51db1cb21e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Torstein=20H=C3=B8nsi?= <torstein@highsoft.com>
Date: Thu, 16 Mar 2017 14:01:11 +0100
Subject: [PATCH] Fixed #6469, series got lost when mixing category data in a
 dual axis chart.

---
 js/parts/Axis.js                         |  6 +-
 samples/unit-tests/axis/category/demo.js | 76 +++++++++++++++++++++++-
 2 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/js/parts/Axis.js b/js/parts/Axis.js
index ab73764c9ed..97298345de5 100644
--- a/js/parts/Axis.js
+++ b/js/parts/Axis.js
@@ -930,7 +930,9 @@ H.Axis.prototype = {
 		}
 
 		// Write the last point's name to the names array
-		this.names[x] = point.name;
+		if (x !== undefined) {
+			this.names[x] = point.name;
+		}
 
 		return x;
 	},
@@ -959,7 +961,7 @@ H.Axis.prototype = {
 					var x;
 					if (point.options) {
 						x = axis.nameToX(point);
-						if (x !== point.x) {
+						if (x !== undefined && x !== point.x) {
 							point.x = x;
 							series.xData[i] = x;
 						}
diff --git a/samples/unit-tests/axis/category/demo.js b/samples/unit-tests/axis/category/demo.js
index dc7bac370aa..d8c4213d9ca 100644
--- a/samples/unit-tests/axis/category/demo.js
+++ b/samples/unit-tests/axis/category/demo.js
@@ -476,8 +476,7 @@ QUnit.test(
         var chart = new Highcharts.Chart({
             chart: {
                 renderTo: 'container',
-                type: 'column',
-
+                type: 'column'
             },
             xAxis: {
                 type: 'category'
@@ -516,3 +515,76 @@ QUnit.test(
 
     }
 );
+
+QUnit.test(
+    'Lost series with multiple axes and mixed configuration (#6469)',
+    function (assert) {
+        var chart = Highcharts.chart('container', {
+            chart: {
+                type: "column",
+                animation: false
+            },
+            xAxis: {
+                type: "category",
+                categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
+            },
+            yAxis: [{
+                lineWidth: 1,
+                title: {
+                    text: 'Primary Axis'
+                },
+            }, {
+                lineWidth: 1,
+                opposite: true,
+                title: {
+                    text: 'Secondary Axis'
+                }
+            }],
+
+            plotOptions: {
+                animation: false
+            },
+
+            series: [{
+                data: [29.9, 71.5, 106.4, 129.2, 144.0, 176.0, 135.6, 148.5, 216.4, 194.1, 95.6, 54.4],
+                yAxis: 0
+            }, {
+                data: [
+                    ["Jan", 14400.0],
+                    ["Feb", 17600.0],
+                    ["Mar", 13500.6],
+                    ["Apr", 14800.5],
+                    ["May", 21600.4],
+                    ["Jun", 19400.1],
+                    ["Jul", 9500.6],
+                    ["Aug", 5400.4],
+                    ["Sep", 2900.9],
+                    ["Oct", 7100.5],
+                    ["Nov", 10600.4],
+                    ["Dec", 12900.2]
+                ],
+                yAxis: 1,
+                type: "spline"
+            }]
+        });
+
+        chart.series[0].hide();
+        chart.series[0].show();
+
+        assert.strictEqual(
+            chart.xAxis[0].tickPositions.length,
+            12,
+            'All ticks intact'
+        );
+        assert.strictEqual(
+            chart.xAxis[0].min,
+            0,
+            'Correct min'
+        );
+        assert.strictEqual(
+            chart.xAxis[0].max,
+            11,
+            'Correct max'
+        );
+    }
+);