From 8f27ca23465d5595d5a0e4653962652ceded334a Mon Sep 17 00:00:00 2001
From: Axel Spoerl <axel.spoerl@qt.io>
Date: Tue, 9 Apr 2024 19:23:33 +0200
Subject: [PATCH] QLayout: Consume ChildRemoved event, when layout is disabled
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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: 6.5 6.2
Change-Id: Ib0a0bb73978d9fc2c9777d300cf38a8c4496b702
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Chris René Lerner <chris.lerner@qt.io>
(cherry picked from commit ef8e548cf1adf8032c030df04e69988f238c77fb)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/widgets/kernel/qlayout.cpp                    |  5 +++--
 tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp | 12 +++++++++---
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/widgets/kernel/qlayout.cpp b/src/widgets/kernel/qlayout.cpp
index 0251ecd7fdc..a826ea75bc6 100644
--- a/src/widgets/kernel/qlayout.cpp
+++ b/src/widgets/kernel/qlayout.cpp
@@ -520,10 +520,11 @@ void QLayoutPrivate::doResize()
 void QLayout::widgetEvent(QEvent *e)
 {
     Q_D(QLayout);
-    if (!d->enabled)
+    const QEvent::Type type = e->type();
+    if (!d->enabled && type != QEvent::ChildRemoved)
         return;
 
-    switch (e->type()) {
+    switch (type) {
     case QEvent::Resize:
         if (d->activated)
             d->doResize();
diff --git a/tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp b/tests/auto/widgets/kernel/qlayout/tst_qlayout.cpp
index 3c3010c3ec3..bd170ca8ab9 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)