QLayout: Consume ChildRemoved event, when layout is disabled

QLayout::widgetEvent() returned early, when the layout was disabled.
That suppressed ChildRemoved events and lead to a crash, when the
layout was enabled again.

Don't return early on ChildRemoved events.
Add an autotest in tst_layout::removeWidget().

Fixes: QTBUG-124151
Pick-to: 6.7 6.5 6.2
Change-Id: Ib0a0bb73978d9fc2c9777d300cf38a8c4496b702
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Chris René Lerner <chris.lerner@qt.io>

1 files changed, 9 insertions, 3 deletions

diff --git a/tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp b/tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp
index 3c3010c3ec..bd170ca8ab 100644
--- a/tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp
+++ b/tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp
@@ -378,10 +378,10 @@ void tst_QLayout::removeWidget()
 {
     QHBoxLayout layout;
     QCOMPARE(layout.count(), 0);
-    QWidget w;
-    layout.addWidget(&w);
+    std::unique_ptr<QWidget> w(new QWidget);
+    layout.addWidget(w.get());
     QCOMPARE(layout.count(), 1);
-    layout.removeWidget(&w);
+    layout.removeWidget(w.get());
     QCOMPARE(layout.count(), 0);
 
     QPointer<QLayout> childLayout(new QHBoxLayout);
@@ -395,6 +395,12 @@ void tst_QLayout::removeWidget()
     QCOMPARE(layout.count(), 0);
 
     QVERIFY(!childLayout.isNull());
+
+    // Test inactive layout consumes ChildRemoved event (QTBUG-124151)
+    layout.addWidget(w.get());
+    layout.setEnabled(false);
+    w.reset();
+    layout.setEnabled(true);
 }
 
 QTEST_MAIN(tst_QLayout)