qquicktextinput: Fix Undo history for IM event

Do not set m_cursor (cursor position) before calling
removeSelectedText() in processInputMethodEvent(QInputMethodEvent *)
method.

Before this change, DeleteSelection command was added to history with
new cursor position. If this command will be later rolled back, cursor
position will not be set correctly. It should be set to position
before handling the event.

Pick-to: 5.15 6.0 6.1
Task-number: QTBUG-90239
Change-Id: Ib5e46d232e6b32f904e745da4f9e5bc03a58963f
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Rami Potinkara <rami.potinkara@qt.io>
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>

1 files changed, 6 insertions, 4 deletions

diff --git a/src/quick/items/qquicktextinput.cpp b/src/quick/items/qquicktextinput.cpp
index dd581c56be..6aec9e8c42 100644
--- a/src/quick/items/qquicktextinput.cpp
+++ b/src/quick/items/qquicktextinput.cpp
@@ -3432,17 +3432,19 @@ void QQuickTextInputPrivate::processInputMethodEvent(QInputMethodEvent *event)
     if (event->replacementStart() <= 0)
         c += event->commitString().length() - qMin(-event->replacementStart(), event->replacementLength());
 
-    m_cursor += event->replacementStart();
-    if (m_cursor < 0)
-        m_cursor = 0;
+    int cursorInsertPos = m_cursor + event->replacementStart();
+    if (cursorInsertPos < 0)
+        cursorInsertPos = 0;
 
     // insert commit string
     if (event->replacementLength()) {
-        m_selstart = m_cursor;
+        m_selstart = cursorInsertPos;
         m_selend = m_selstart + event->replacementLength();
         m_selend = qMin(m_selend, m_text.length());
         removeSelectedText();
     }
+    m_cursor = cursorInsertPos;
+
     if (!event->commitString().isEmpty()) {
         internalInsert(event->commitString());
         cursorPositionChanged = true;