Ensure that when the time axis accesses `data.labels` it actually exists (#5750)

diff --git a/src/scales/scale.time.js b/src/scales/scale.time.js
index 2496a487c3ef0d257e7e8d7677c9bbf84c1fb79b..405d8ff8c80daf1e6a8a771c7d617524f4c81a66 100644 (file)
--- a/src/scales/scale.time.js
+++ b/src/scales/scale.time.js
@@ -534,10 +534,11 @@ module.exports = function() {
                        var datasets = [];
                        var labels = [];
                        var i, j, ilen, jlen, data, timestamp;
+                       var dataLabels = chart.data.labels || [];
 
                        // Convert labels to timestamps
-                       for (i = 0, ilen = chart.data.labels.length; i < ilen; ++i) {
-                               labels.push(parse(chart.data.labels[i], me));
+                       for (i = 0, ilen = dataLabels.length; i < ilen; ++i) {
+                               labels.push(parse(dataLabels[i], me));
                        }
 
                        // Convert data to timestamps