From 47c6bd6963ac163f714bdeb9ad5704ed58395e77 Mon Sep 17 00:00:00 2001
From: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com>
Date: Fri, 24 Apr 2020 09:45:44 +0200
Subject: [PATCH] Fix PromQuery cascader when selected option has no children
 (#23835)

---
 .../datasource/prometheus/components/PromQueryField.tsx      | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/public/app/plugins/datasource/prometheus/components/PromQueryField.tsx b/public/app/plugins/datasource/prometheus/components/PromQueryField.tsx
index f0390639d91..efa1326d6ae 100644
--- a/public/app/plugins/datasource/prometheus/components/PromQueryField.tsx
+++ b/public/app/plugins/datasource/prometheus/components/PromQueryField.tsx
@@ -199,8 +199,9 @@ class PromQueryField extends React.PureComponent<PromQueryFieldProps, PromQueryF
   onChangeMetrics = (values: string[], selectedOptions: CascaderOption[]) => {
     let query;
     if (selectedOptions.length === 1) {
-      if (selectedOptions[0].children.length === 0) {
-        query = selectedOptions[0].value;
+      const selectedOption = selectedOptions[0];
+      if (!selectedOption.children || selectedOption.children.length === 0) {
+        query = selectedOption.value;
       } else {
         // Ignore click on group
         return;