From 7c4974c36a2471203b5577fa0c3b5b011239045d Mon Sep 17 00:00:00 2001
From: erri120 <erri120@fossmailer.de>
Date: Fri, 13 Dec 2024 17:05:58 +0100
Subject: [PATCH] Fix incrementing `-1` indices

Fixes https://github.com/Cysharp/ObservableCollections/issues/89
---
 .../ObservableCollectionR3Extensions.cs                       | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/ObservableCollections.R3/ObservableCollectionR3Extensions.cs b/src/ObservableCollections.R3/ObservableCollectionR3Extensions.cs
index 21adea2..16d681b 100644
--- a/src/ObservableCollections.R3/ObservableCollectionR3Extensions.cs
+++ b/src/ObservableCollections.R3/ObservableCollectionR3Extensions.cs
@@ -167,10 +167,12 @@ protected override void Handler(in NotifyCollectionChangedEventArgs<T> eventArgs
                             eventArgs.Action,
                             item,
                             eventArgs.OldItem,
-                            i++,
+                            newStartingIndex: i,
                             eventArgs.OldStartingIndex,
                             eventArgs.SortOperation);
 
+                        if (eventArgs.NewStartingIndex != -1) i++;
+
                         observer.OnNext(newArgs);
                     }
                 }