QObject: restore flags printing in dumpObjectTree()

This was lost when QtCore, QtGui and QtWidgets were split up. Restored
now via a virtual function on QObjectPrivate.

Chose to return std::string instead of QString or QByteArray because
its SSO is usually sufficient to hold these flag strings.

[ChangeLog][QtCore][QObject] Restored printing of Qt3-style
information from dumpObjectTree().

[ChangeLog][QtWidgets][QWidget] Restored printing of Qt3-style
information from QWidget::dumpObjectTree().

Fixes: QTBUG-101732
Change-Id: I39ff5728ea5f5abbdbf81b5d7e13b8d16b6ee8b7
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

1 files changed, 40 insertions, 0 deletions

diff --git a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
index ea0d5e8871..040ad17c74 100644
--- a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
+++ b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
@@ -335,6 +335,8 @@ private slots:
     void resizeInPaintEvent();
     void opaqueChildren();
 
+    void dumpObjectTree();
+
     void setMaskInResizeEvent();
     void moveInResizeEvent();
 
@@ -9060,6 +9062,44 @@ void tst_QWidget::opaqueChildren()
     QCOMPARE(qt_widget_private(&grandChild)->getOpaqueChildren(), QRegion());
 }
 
+void tst_QWidget::dumpObjectTree()
+{
+    QWidget w;
+    w.setWindowTitle(QLatin1String(QTest::currentTestFunction()));
+    Q_SET_OBJECT_NAME(w);
+    w.move(100, 100);
+    w.resize(500, 500);
+
+    QLineEdit le(&w);
+    Q_SET_OBJECT_NAME(le);
+    le.resize(500, 500);
+
+    {
+        const char * const expected[] = {
+            "QWidget::w I",
+            "    QLineEdit::le I",
+            "        QWidgetLineControl:: ",
+        };
+        for (const char *line : expected)
+            QTest::ignoreMessage(QtDebugMsg, line);
+        w.dumpObjectTree();
+    }
+
+    w.show();
+    QApplication::setActiveWindow(&w);
+    QVERIFY(QTest::qWaitForWindowActive(&w));
+
+    {
+        const char * const expected[] = {
+            "QWidget::w <500x500+100+100>",
+            "    QLineEdit::le F<500x500+0+0>",
+            "        QWidgetLineControl:: ",
+        };
+        for (const char *line : expected)
+            QTest::ignoreMessage(QtDebugMsg, line);
+        w.dumpObjectTree();
+    }
+}
 
 class MaskSetWidget : public QWidget
 {