Fix crash when connecting a new screen

In QWaylandWindow::virtualSiblings, don't include screens that have not been
added yet. I.e. QWaylandScreens for which QPlatformIntegration::screenAdded has
not yet been called.

There are two reasons why this crash wasn't covered by the
removePrimaryScreen() test. First of all, the mock output didn't send
wl_output.done events when updating the mode/geometry. These wayland events are
what causes QWindowSystemInterface::handleScreenGeometryChange() to be called
(where virtualSiblings are called).

Furthermore, virtualSiblings is only called when the geometry actually changes,
so add a new test that changes the screen geometry of the existing screen while
a new one is being added (i.e. moves it to the right).

Task-number: QTBUG-62044
Change-Id: I623fbf8799d21c6b9293e7120ded301277639cc6
Reviewed-by: David Edmundson <davidedmundson@kde.org>
Reviewed-by: Aleix Pol
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

1 files changed, 25 insertions, 2 deletions

diff --git a/tests/auto/client/shared/mockoutput.cpp b/tests/auto/client/shared/mockoutput.cpp
index 7d7b7413a..13e0524ad 100644
--- a/tests/auto/client/shared/mockoutput.cpp
+++ b/tests/auto/client/shared/mockoutput.cpp
@@ -54,6 +54,16 @@ void Compositor::sendRemoveOutput(void *data, const QList<QVariant> &parameters)
     delete output;
 }
 
+void Compositor::sendOutputGeometry(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Q_ASSERT(compositor);
+    Output *output = resolveOutput(parameters.first());
+    Q_ASSERT(output);
+    QRect geometry = parameters.at(1).toRect();
+    output->sendGeometryAndMode(geometry);
+}
+
 void Compositor::setOutputMode(void *data, const QList<QVariant> &parameters)
 {
     Compositor *compositor = static_cast<Compositor *>(data);
@@ -74,16 +84,29 @@ Output::Output(wl_display *display, const QSize &resolution, const QPoint &posit
 
 void Output::setCurrentMode(const QSize &size)
 {
-    qDebug() << Q_FUNC_INFO << size;
     m_size = size;
-    for (Resource *resource : resourceMap())
+    for (Resource *resource : resourceMap()) {
+        sendCurrentMode(resource);
+        send_done(resource->handle);
+    }
+}
+
+void Output::sendGeometryAndMode(const QRect &geometry)
+{
+    m_size = geometry.size();
+    m_position = geometry.topLeft();
+    for (Resource *resource : resourceMap()) {
+        sendGeometry(resource);
         sendCurrentMode(resource);
+        send_done(resource->handle);
+    }
 }
 
 void Output::output_bind_resource(QtWaylandServer::wl_output::Resource *resource)
 {
     sendGeometry(resource);
     sendCurrentMode(resource);
+    send_done(resource->handle);
 }
 
 void Output::sendGeometry(Resource *resource)