From bf554d121cc116457f3432f2448314381b234016 Mon Sep 17 00:00:00 2001
From: Giordano Ricci <me@giordanoricci.com>
Date: Fri, 27 Oct 2023 14:37:23 +0100
Subject: [PATCH] Explore: Avoid reinitializing graph on every query run
 (#77281)

---
 .../app/features/explore/Graph/useStructureRev.test.ts   | 9 +++++++++
 public/app/features/explore/Graph/useStructureRev.ts     | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/public/app/features/explore/Graph/useStructureRev.test.ts b/public/app/features/explore/Graph/useStructureRev.test.ts
index dd808005929..650e1ac0a72 100644
--- a/public/app/features/explore/Graph/useStructureRev.test.ts
+++ b/public/app/features/explore/Graph/useStructureRev.test.ts
@@ -51,6 +51,15 @@ beforeAll(() => {
 describe('useStructureRev', () => {
   afterEach(() => resetCounters());
 
+  // mirrors the logic in componentDidUpdate in packages/grafana-ui/src/components/GraphNG/GraphNG.tsx,
+  // which treats all falsy values for structureRev as a signal to reconfig the graph
+  it('should start from a thruthy value', () => {
+    let frames: DataFrame[] = [toDataFrame({ fields: [{ name: 'time', type: FieldType.time, values: [1, 2, 3] }] })];
+    const { result } = renderHook((frames) => useStructureRev(frames), { initialProps: frames });
+
+    expect(result.current).not.toBeFalsy();
+  });
+
   it('should increment only when relevant fields in frame change', () => {
     let frames: DataFrame[] = [toDataFrame({ fields: [{ name: 'time', type: FieldType.time, values: [1, 2, 3] }] })];
     const { result, rerender } = renderHook((frames) => useStructureRev(frames), { initialProps: frames });
diff --git a/public/app/features/explore/Graph/useStructureRev.ts b/public/app/features/explore/Graph/useStructureRev.ts
index 23490e4d170..cb51571a42c 100644
--- a/public/app/features/explore/Graph/useStructureRev.ts
+++ b/public/app/features/explore/Graph/useStructureRev.ts
@@ -4,7 +4,7 @@ import { useCounter, usePrevious } from 'react-use';
 import { DataFrame, compareArrayValues, compareDataFrameStructures } from '@grafana/data';
 
 export function useStructureRev(frames: DataFrame[]) {
-  const [structureRev, { inc }] = useCounter(0);
+  const [structureRev, { inc }] = useCounter(1);
   const previousFrames = usePrevious(frames);
 
   // We need to increment structureRev when the number of series changes.