Make updateChart robust to missing data in dataset. Relevant for other update mechanisms as in chartjs-plugin-streaming. (#434)

Author: tobbee

src/index.js

@@ -207,7 +207,8 @@ class ChartComponent extends React.Component {
       const current =
         currentDatasetsIndexed[this.props.datasetKeyProvider(next)];
 
-      if (current && current.type === next.type) {
+      if (current && current.type === next.type && next.data) {
+        // Be robust to no data. Relevant for other update mechanisms as in chartjs-plugin-streaming.
         // The data array must be edited in place. As chart.js adds listeners to it.
         current.data.splice(next.data.length);
         next.data.forEach((point, pid) => {