Client: Don't send illegal wl_pointer.set_cursor requests

When the cursor focus' wl_surface is destroyed, or the pointer leaves a
surface, we have to reset the enter serial to avoid sending illegal set_cursor
requests.

Change-Id: I0c886e4123acb4aebd325b07bf15b9d3fa8589da
Reviewed-by: Giulio Camuffo <giulio.camuffo@kdab.com>

2 files changed, 36 insertions, 4 deletions

diff --git a/tests/auto/client/seatv4/tst_seatv4.cpp b/tests/auto/client/seatv4/tst_seatv4.cpp
index 771307d7e..7dc2e727a 100644
--- a/tests/auto/client/seatv4/tst_seatv4.cpp
+++ b/tests/auto/client/seatv4/tst_seatv4.cpp
@@ -70,6 +70,7 @@ private slots:
     void createsPointer();
     void setsCursorOnEnter();
     void usesEnterSerial();
+    void focusDestruction();
     void mousePress();
     void simpleAxis_data();
     void simpleAxis();
@@ -147,12 +148,43 @@ void tst_seatv4::usesEnterSerial()
     uint enterSerial = exec([=] {
         return pointer()->sendEnter(xdgSurface()->m_surface, {32, 32});
     });
-    QCOMPOSITOR_TRY_VERIFY(pointer()->cursorSurface());
+    QCOMPOSITOR_TRY_VERIFY(cursorSurface());
 
     QTRY_COMPARE(setCursorSpy.count(), 1);
     QCOMPARE(setCursorSpy.takeFirst().at(0).toUInt(), enterSerial);
 }
 
+void tst_seatv4::focusDestruction()
+{
+    QSignalSpy setCursorSpy(exec([=] { return pointer(); }), &Pointer::setCursor);
+    QRasterWindow window;
+    window.resize(64, 64);
+    window.show();
+    QCOMPOSITOR_TRY_VERIFY(xdgSurface() && xdgSurface()->m_committedConfigureSerial);
+    // Setting a cursor now is not allowed since there has been no enter event
+    QCOMPARE(setCursorSpy.count(), 0);
+
+    uint enterSerial = exec([=] {
+        return pointer()->sendEnter(xdgSurface()->m_surface, {32, 32});
+    });
+    QCOMPOSITOR_TRY_VERIFY(cursorSurface());
+    QTRY_COMPARE(setCursorSpy.count(), 1);
+    QCOMPARE(setCursorSpy.takeFirst().at(0).toUInt(), enterSerial);
+
+    // Destroy the focus
+    window.close();
+
+    QRasterWindow window2;
+    window2.resize(64, 64);
+    window2.show();
+    window2.setCursor(Qt::WaitCursor);
+    QCOMPOSITOR_TRY_VERIFY(xdgSurface() && xdgSurface()->m_committedConfigureSerial);
+
+    // Setting a cursor now is not allowed since there has been no enter event
+    xdgPingAndWaitForPong();
+    QCOMPARE(setCursorSpy.count(), 0);
+}
+
 void tst_seatv4::mousePress()
 {
     class Window : public QRasterWindow {
diff --git a/tests/auto/client/shared/coreprotocol.cpp b/tests/auto/client/shared/coreprotocol.cpp
index c4dc3f341..729d481f8 100644
--- a/tests/auto/client/shared/coreprotocol.cpp
+++ b/tests/auto/client/shared/coreprotocol.cpp
@@ -261,6 +261,7 @@ uint Pointer::sendEnter(Surface *surface, const QPointF &position)
 
     uint serial = m_seat->m_compositor->nextSerial();
     m_enterSerials << serial;
+    m_cursorRole = nullptr; // According to the protocol, the pointer image is undefined after enter
 
     wl_client *client = surface->resource()->client();
     const auto pointerResources = resourceMap().values(client);
@@ -320,9 +321,8 @@ void Pointer::pointer_set_cursor(Resource *resource, uint32_t serial, wl_resourc
     QVERIFY(s);
 
     if (s->m_role) {
-        auto *cursorRole = CursorRole::fromSurface(s);
-        QVERIFY(cursorRole);
-        QVERIFY(cursorRole == m_cursorRole);
+        m_cursorRole = CursorRole::fromSurface(s);
+        QVERIFY(m_cursorRole);
     } else {
         m_cursorRole = new CursorRole(s); //TODO: make sure we don't leak CursorRole
         s->m_role = m_cursorRole;