From 83d203561d3bf14942f84fbb5a94cc2513bff4c3 Mon Sep 17 00:00:00 2001
From: Don Ho <don.h@free.fr>
Date: Mon, 3 Jul 2023 21:51:35 +0200
Subject: [PATCH] Fix Change History wrong display after "Reload from Disk"
 command

The code for fixing is from Change Lines plugin:
https://github.com/vinsworldcom/nppChangedLines/blob/main/PluginDefinition.cpp

Fix #12319, fix #12261, fix #13735, close #13858
---
 PowerEditor/src/Notepad_plus.cpp | 13 +++++++++++++
 PowerEditor/src/Notepad_plus.h   |  2 ++
 PowerEditor/src/NppIO.cpp        |  4 ++++
 3 files changed, 19 insertions(+)

diff --git a/PowerEditor/src/Notepad_plus.cpp b/PowerEditor/src/Notepad_plus.cpp
index 1527c78d2..d33bc9f37 100644
--- a/PowerEditor/src/Notepad_plus.cpp
+++ b/PowerEditor/src/Notepad_plus.cpp
@@ -8656,3 +8656,16 @@ HBITMAP Notepad_plus::generateSolidColourMenuItemIcon(COLORREF colour)
 
 	return hNewBitmap;
 }
+
+
+void Notepad_plus::clearChangesHistory()
+{
+	Sci_Position pos = (Sci_Position)::SendMessage(_pEditView->getHSelf(), SCI_GETCURRENTPOS, 0, 0);
+	int chFlags = (int)::SendMessage(_pEditView->getHSelf(), SCI_GETCHANGEHISTORY, 0, 0);
+
+	SendMessage(_pEditView->getHSelf(), SCI_EMPTYUNDOBUFFER, 0, 0);
+	SendMessage(_pEditView->getHSelf(), SCI_SETCHANGEHISTORY, SC_CHANGE_HISTORY_DISABLED, 0);
+
+	SendMessage(_pEditView->getHSelf(), SCI_SETCHANGEHISTORY, chFlags, 0);
+	SendMessage(_pEditView->getHSelf(), SCI_GOTOPOS, pos, 0);
+}
diff --git a/PowerEditor/src/Notepad_plus.h b/PowerEditor/src/Notepad_plus.h
index 58f4ebac3..1a35a24af 100644
--- a/PowerEditor/src/Notepad_plus.h
+++ b/PowerEditor/src/Notepad_plus.h
@@ -644,4 +644,6 @@ private:
 	void updateCommandShortcuts();
 
 	HBITMAP generateSolidColourMenuItemIcon(COLORREF colour);
+
+	void clearChangesHistory();
 };
diff --git a/PowerEditor/src/NppIO.cpp b/PowerEditor/src/NppIO.cpp
index f5f8fa011..11691e810 100644
--- a/PowerEditor/src/NppIO.cpp
+++ b/PowerEditor/src/NppIO.cpp
@@ -588,6 +588,10 @@ bool Notepad_plus::doReload(BufferID id, bool alert)
 	// Once reload is complete, activate buffer which will take care of
 	// many settings such as update status bar, clickable link etc.
 	activateBuffer(id, currentView(), true);
+
+	if (NppParameters::getInstance().getSVP()._isChangeHistoryEnabled4NextSession)
+		clearChangesHistory();
+
 	return res;
 }