From 913b749fa96f4a7d9dc0b850c06306f126e412a0 Mon Sep 17 00:00:00 2001
From: Bart <9132501-flyingsheep@users.noreply.gitlab.com>
Date: Mon, 7 Apr 2025 22:30:41 +0200
Subject: [PATCH] LazUtf8: correct a StartCharIndex < 1 in Utf8Insert. Reason:
 consistent with System.Insert().

---
 components/lazutils/lazutf8.pas | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/components/lazutils/lazutf8.pas b/components/lazutils/lazutf8.pas
index 3b97933dbf..c9f94117b8 100644
--- a/components/lazutils/lazutf8.pas
+++ b/components/lazutils/lazutf8.pas
@@ -1190,6 +1190,8 @@ procedure UTF8Insert(const source: String; var s: String; StartCharIndex: PtrInt
 var
   StartBytePos: PChar;
 begin
+  if StartCharIndex < 1 then
+    StartCharIndex := 1;  //Insert() does this correction too
   StartBytePos:=UTF8CodepointStart(PChar(s),length(s),StartCharIndex-1);
   if StartBytePos <> nil then
     Insert(source, s, StartBytePos-PChar(s)+1);