commit 7fa34554e8d0b2222658f02125b0e71959e0e1fc
Author: Richard Moe Gustavsen <richard.gustavsen@qt.io>
Date:   Tue Nov 14 13:19:41 2023 +0100

    TableView, 5.15 patch: don't emit rows and columns changed while rebuilding

diff --git a/src/quick/items/qquicktableview.cpp b/src/quick/items/qquicktableview.cpp
index 2a8a8ccae0..5334cae55a 100644
--- a/src/quick/items/qquicktableview.cpp
+++ b/src/quick/items/qquicktableview.cpp
@@ -1025,21 +1025,22 @@ void QQuickTableViewPrivate::forceLayout()
 
     const QSize actualTableSize = calculateTableSize();
     if (tableSize != actualTableSize) {
-        // This can happen if the app is calling forceLayout while
-        // the model is updated, but before we're notified about it.
-        rebuildOptions = RebuildOption::All;
-    } else {
-        // Resizing a column (or row) can result in the table going from being
-        // e.g completely inside the viewport to go outside. And in the latter
-        // case, the user needs to be able to scroll the viewport, also if
-        // flags such as Flickable.StopAtBounds is in use. So we need to
-        // update contentWidth/Height to support that case.
-        rebuildOptions = RebuildOption::LayoutOnly
-                | RebuildOption::CalculateNewContentWidth
-                | RebuildOption::CalculateNewContentHeight
-                | checkForVisibilityChanges();
+        // The table size will have changed if forceLayout is called after
+        // the row count in the model has changed, but before we received
+        // a rowsInsertedCallback about it (and vice versa for columns).
+        rebuildOptions |= RebuildOption::ViewportOnly;
     }
 
+    // Resizing a column (or row) can result in the table going from being
+    // e.g completely inside the viewport to go outside. And in the latter
+    // case, the user needs to be able to scroll the viewport, also if
+    // flags such as Flickable.StopAtBounds is in use. So we need to
+    // update contentWidth/Height to support that case.
+    rebuildOptions |= RebuildOption::LayoutOnly
+            | RebuildOption::CalculateNewContentWidth
+            | RebuildOption::CalculateNewContentHeight
+            | checkForVisibilityChanges();
+
     scheduleRebuildTable(rebuildOptions);
 
     auto rootView = rootSyncView();
@@ -1302,21 +1303,6 @@ qreal QQuickTableViewPrivate::sizeHintForRow(int row)
     return rowHeight;
 }
 
-void QQuickTableViewPrivate::updateTableSize()
-{
-    // tableSize is the same as row and column count, and will always
-    // be the same as the number of rows and columns in the model.
-    Q_Q(QQuickTableView);
-
-    const QSize prevTableSize = tableSize;
-    tableSize = calculateTableSize();
-
-    if (prevTableSize.width() != tableSize.width())
-        emit q->columnsChanged();
-    if (prevTableSize.height() != tableSize.height())
-        emit q->rowsChanged();
-}
-
 QSize QQuickTableViewPrivate::calculateTableSize()
 {
     QSize size(0, 0);
@@ -1714,6 +1700,8 @@ void QQuickTableViewPrivate::processRebuildTable()
             else
                 Q_TABLEVIEW_UNREACHABLE(rebuildOptions);
         }
+
+        tableSizeBeforeRebuild = tableSize;
     }
 
     moveToNextRebuildState();
@@ -1771,6 +1759,13 @@ void QQuickTableViewPrivate::processRebuildTable()
             return;
     }
 
+    if (rebuildState == RebuildState::Done) {
+        if (tableSizeBeforeRebuild.width() != tableSize.width())
+            emit q->columnsChanged();
+        if (tableSizeBeforeRebuild.height() != tableSize.height())
+            emit q->rowsChanged();
+    }
+
     Q_TABLEVIEW_ASSERT(rebuildState == RebuildState::Done, int(rebuildState));
     qCDebug(lcTableViewDelegateLifecycle()) << "rebuild complete:" << q;
 }
@@ -1892,7 +1887,7 @@ void QQuickTableViewPrivate::calculateTopLeft(QPoint &topLeftCell, QPointF &topL
 
 void QQuickTableViewPrivate::beginRebuildTable()
 {
-    updateTableSize();
+    tableSize = calculateTableSize();
 
     QPoint topLeft;
     QPointF topLeftPos;
diff --git a/src/quick/items/qquicktableview_p_p.h b/src/quick/items/qquicktableview_p_p.h
index 758c0308b8..52ef3546f1 100644
--- a/src/quick/items/qquicktableview_p_p.h
+++ b/src/quick/items/qquicktableview_p_p.h
@@ -311,6 +311,8 @@ public:
     QList<QPointer<QQuickTableView> > syncChildren;
     Qt::Orientations assignedSyncDirection = Qt::Horizontal | Qt::Vertical;
 
+    QSize tableSizeBeforeRebuild;
+
     const static QPoint kLeft;
     const static QPoint kRight;
     const static QPoint kUp;
@@ -329,7 +331,6 @@ public:
     qreal sizeHintForColumn(int column);
     qreal sizeHintForRow(int row);
     QSize calculateTableSize();
-    void updateTableSize();
 
     inline bool isColumnHidden(int column);
     inline bool isRowHidden(int row);