From fcb70e903af8ad6dd4f24449c64e6fedd4ba2c23 Mon Sep 17 00:00:00 2001
From: wp_xyz <wp_xxyyzzz@gmx.net>
Date: Thu, 3 Feb 2022 00:33:51 +0100
Subject: [PATCH] TAChart: Fix TBoxAndWhiskerSeries crashing when MinYValue or
 MaxYValue is queried and the series is empty.

---
 components/tachart/tamultiseries.pas | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/components/tachart/tamultiseries.pas b/components/tachart/tamultiseries.pas
index ff8d477d2d..070e09a3e9 100644
--- a/components/tachart/tamultiseries.pas
+++ b/components/tachart/tamultiseries.pas
@@ -1157,6 +1157,9 @@ var
 
 begin
   Result := Source.ExtentList;
+  if Source.Count = 0 then
+    exit;
+  
   // Show first and last boxes fully.
   j := -1;
   x := NaN;