From 1d56bd112582f50aa4b3510c1e8fc054d7b00031 Mon Sep 17 00:00:00 2001
From: "Grot (@grafanabot)" <43478413+grafanabot@users.noreply.github.com>
Date: Tue, 23 Aug 2022 10:22:35 +0200
Subject: [PATCH] TimeSeries: Fix crash when min >= max in config (#54069)
 (#54077)

* TimeSeries: fix crash when min === max in config

* stat sparkline, too

* better types

(cherry picked from commit 530dd63ac62fac5d5f5a4ece3081db0f9ceb6709)

Co-authored-by: Leon Sorokin <leeoniya@gmail.com>
---
 .betterer.results                                        | 3 +--
 .../grafana-ui/src/components/Sparkline/Sparkline.tsx    | 9 ++++-----
 .../src/components/uPlot/config/UPlotScaleBuilder.ts     | 6 ++++++
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/.betterer.results b/.betterer.results
index a1fb3cf1be9..75c095e1d2a 100644
--- a/.betterer.results
+++ b/.betterer.results
@@ -2040,8 +2040,7 @@ exports[`better eslint`] = {
       [0, 0, 0, "Do not use any type assertions.", "5"]
     ],
     "packages/grafana-ui/src/components/Sparkline/Sparkline.tsx:5381": [
-      [0, 0, 0, "Do not use any type assertions.", "0"],
-      [0, 0, 0, "Do not use any type assertions.", "1"]
+      [0, 0, 0, "Do not use any type assertions.", "0"]
     ],
     "packages/grafana-ui/src/components/Spinner/Spinner.story.tsx:5381": [
       [0, 0, 0, "Do not use any type assertions.", "0"]
diff --git a/packages/grafana-ui/src/components/Sparkline/Sparkline.tsx b/packages/grafana-ui/src/components/Sparkline/Sparkline.tsx
index 270b103aa9f..ba02f8db302 100644
--- a/packages/grafana-ui/src/components/Sparkline/Sparkline.tsx
+++ b/packages/grafana-ui/src/components/Sparkline/Sparkline.tsx
@@ -93,7 +93,7 @@ export class Sparkline extends PureComponent<SparklineProps, State> {
     }
   }
 
-  getYRange(field: Field) {
+  getYRange(field: Field): Range.MinMax {
     let { min, max } = this.state.alignedDataFrame.fields[1].state?.range!;
 
     if (min === max) {
@@ -103,12 +103,11 @@ export class Sparkline extends PureComponent<SparklineProps, State> {
         min = 0;
         max! *= 2;
       }
+
+      return [min, max!];
     }
 
-    return [
-      Math.max(min!, field.config.min ?? -Infinity),
-      Math.min(max!, field.config.max ?? Infinity),
-    ] as Range.MinMax;
+    return [Math.max(min!, field.config.min ?? -Infinity), Math.min(max!, field.config.max ?? Infinity)];
   }
 
   prepareConfig(data: DataFrame) {
diff --git a/packages/grafana-ui/src/components/uPlot/config/UPlotScaleBuilder.ts b/packages/grafana-ui/src/components/uPlot/config/UPlotScaleBuilder.ts
index db2bb0309d1..448d68d1f15 100644
--- a/packages/grafana-ui/src/components/uPlot/config/UPlotScaleBuilder.ts
+++ b/packages/grafana-ui/src/components/uPlot/config/UPlotScaleBuilder.ts
@@ -83,6 +83,12 @@ export class UPlotScaleBuilder extends PlotConfigBuilder<ScaleProps, Scale> {
         minMax[1] = hardMax!;
       }
 
+      // guard against invalid y ranges
+      if (minMax[0]! >= minMax[1]!) {
+        minMax[0] = 0;
+        minMax[1] = 100;
+      }
+
       return minMax;
     };