Sorting bug in QTableView fix

When the DisplayRole is identical for two or more items, any
modification of one item (e.g. backgroundColorRole) may trigger a
re-ordering, which is obviously not an behaviour to be expected.
Same fix as the one used for QTreewidget in
c9eacfa1c791e2d228a3c8f0c119d02d7f46ee02.

Task-number: QTBUG-4856
Task-number: 262056
Reviewed-by: Olivier Goffart

2 files changed, 23 insertions, 0 deletions

diff --git a/src/gui/itemviews/qtablewidget.cpp b/src/gui/itemviews/qtablewidget.cpp
index a086498..65758b8 100644
--- a/src/gui/itemviews/qtablewidget.cpp
+++ b/src/gui/itemviews/qtablewidget.cpp
@@ -571,6 +571,8 @@ void QTableModel::ensureSorted(int column, Qt::SortOrder order,
         colItems.remove(oldRow);
         vit = sortedInsertionIterator(vit, colItems.end(), order, item);
         int newRow = qMax((int)(vit - colItems.begin()), 0);
+        if ((newRow < oldRow) && !(*item < *colItems.at(oldRow - 1)))
+            newRow = oldRow;
         vit = colItems.insert(vit, item);
         if (newRow != oldRow) {
             changed = true;
diff --git a/tests/auto/qtablewidget/tst_qtablewidget.cpp b/tests/auto/qtablewidget/tst_qtablewidget.cpp
index 5aa2d1d..b85851f 100644
--- a/tests/auto/qtablewidget/tst_qtablewidget.cpp
+++ b/tests/auto/qtablewidget/tst_qtablewidget.cpp
@@ -102,6 +102,7 @@ private slots:
     void cellWidget();
     void task231094();
     void task219380_removeLastRow();
+    void task262056_sortDuplicate();
 
 private:
     QTableWidget *testWidget;
@@ -1474,6 +1475,26 @@ void tst_QTableWidget::task219380_removeLastRow()
     QCOMPARE(testWidget->cellWidget(18, 0)->geometry(), testWidget->visualItemRect(&item));
 }
 
+void tst_QTableWidget::task262056_sortDuplicate()
+{
+    testWidget->setColumnCount(2);
+    testWidget->setRowCount(8);
+    testWidget->setSortingEnabled(true);
+    QStringList items = (QStringList() << "AAA" << "BBB" << "CCC" << "CCC" << "DDD"\
+                         << "EEE" << "FFF" << "GGG");
+    for (int i = 0; i<8; i++ ) {
+        QTableWidgetItem *twi = new QTableWidgetItem(items.at(i));
+        testWidget->setItem(i,0,twi);
+        testWidget->setItem(i,1,new QTableWidgetItem(QString("item %1").arg(i)));
+    }
+    testWidget->sortItems(0, Qt::AscendingOrder);
+    QSignalSpy layoutChangedSpy(testWidget->model(), SIGNAL(layoutChanged()));
+    testWidget->item(3,0)->setBackgroundColor(Qt::red);
+
+    QCOMPARE(layoutChangedSpy.count(),0);
+
+}
+
 
 QTEST_MAIN(tst_QTableWidget)
 #include "tst_qtablewidget.moc"