From 17992fbab738450c892ee283a642b8f4697fafde Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sun, 16 Aug 2020 11:10:20 +0200
Subject: [PATCH] LibGUI: Resort SortingProxyModel when source invalidates if
 possible

If the source model invalidates with indexes still good, we can simply
resort the proxy's mappings.
---
 Libraries/LibGUI/SortingProxyModel.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Libraries/LibGUI/SortingProxyModel.cpp b/Libraries/LibGUI/SortingProxyModel.cpp
index e25f179b8d..0752dc1206 100644
--- a/Libraries/LibGUI/SortingProxyModel.cpp
+++ b/Libraries/LibGUI/SortingProxyModel.cpp
@@ -44,7 +44,10 @@ SortingProxyModel::~SortingProxyModel()
 
 void SortingProxyModel::invalidate(unsigned int flags)
 {
-    m_mappings.clear();
+    if (flags == UpdateFlag::DontInvalidateIndexes)
+        sort(m_last_key_column, m_last_sort_order);
+    else
+        m_mappings.clear();
     did_update(flags);
 }