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nreese · nreese · commit 4438e94e2abb · 2020-07-02T10:17:19.000-06:00
diff --git a/x-pack/plugins/maps/public/classes/sources/es_agg_source/es_agg_source.js b/x-pack/plugins/maps/public/classes/sources/es_agg_source/es_agg_source.js
@@ -50,6 +50,7 @@ export class AbstractESAggSource extends AbstractESSource {
 
   getMetricFields() {
     const metrics = this._metricFields.filter((esAggField) => esAggField.isValid());
+    // Handle case where metrics is empty because older saved object state is empty array or there are no valid aggs.
     return metrics.length === 0
       ? esAggFieldsFactory({ type: AGG_TYPE.COUNT }, this, this.getOriginForField())
       : metrics;
