xcb: Delete touch points without target windows

When XCB_INPUT_TOUCH_BEGIN closes a popup, we then receive
XCB_INPUT_TOUCH_END, and cannot find a target window (because it's
destroyed). If we don't deliver it, we need to at least clear the
stored point from QPointingDevicePrivate::activePoints. Then when
we deliver the next touch press, m_fakeMouseSourcePointId also
needs to be reset.

It's now even more paramount that autotests (and real-world
touchscreens) must never omit any active touchpoint from a touch event.
If a point doesn't move, it must be included in the QTouchEvent, with
Stationary state. If not, QGuiApp::processTouchEvent() could generate
multiple TouchBegin events in a row, which gets other bits of logic
confused, here and there.

Fixes: QTBUG-94557
Fixes: QTBUG-98519
Fixes: QTBUG-102751
Fixes: QTBUG-103706
Pick-to: 6.2 6.3 5.15
Change-Id: Ia95e410a2bb8bc7784aa5d296fac2b89e53a9f55
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

1 files changed, 39 insertions, 1 deletions

diff --git a/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp b/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
index 1cf0c43d98..dafa69fb96 100644
--- a/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
+++ b/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
@@ -1157,14 +1157,18 @@ void tst_QWindow::touchToMouseTranslation()
     QVERIFY(QTest::qWaitForWindowExposed(&window));
 
     QList<QWindowSystemInterface::TouchPoint> points;
-    QWindowSystemInterface::TouchPoint tp1, tp2;
+    QWindowSystemInterface::TouchPoint tp1, tp2, tp3;
     const QRectF pressArea(101, 102, 4, 4);
+    const QRectF pressArea1(107, 110, 4, 4);
     const QRectF moveArea(105, 108, 4, 4);
     tp1.id = 1;
     tp1.state = QEventPoint::State::Pressed;
     tp1.area = QHighDpi::toNativePixels(pressArea, &window);
     tp2.id = 2;
     tp2.state = QEventPoint::State::Pressed;
+    tp3.id = 3;
+    tp3.state = QEventPoint::State::Pressed;
+    tp3.area = QHighDpi::toNativePixels(pressArea1, &window);
     points << tp1 << tp2;
     QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
     // Now an update but with changed list order. The mouse event should still
@@ -1246,6 +1250,40 @@ void tst_QWindow::touchToMouseTranslation()
     QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
     QCoreApplication::processEvents();
     QTRY_COMPARE(window.mouseReleaseButton, 1);
+
+    points.clear();
+    points.append(tp1);
+    points[0].state = QEventPoint::State::Pressed;
+    QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
+    QCoreApplication::processEvents();
+    points.clear();
+    points.append(tp2);
+    points[0].state = QEventPoint::State::Pressed;
+    QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
+    QCoreApplication::processEvents();
+    points.clear();
+    points.append(tp3);
+    points[0].state = QEventPoint::State::Pressed;
+    QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
+    QCoreApplication::processEvents();
+    QTRY_COMPARE(window.mousePressButton, 1);
+
+    points.clear();
+    points.append(tp2);
+    points[0].state = QEventPoint::State::Released;
+    QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
+    QCoreApplication::processEvents();
+    points.clear();
+    points.append(tp3);
+    points[0].state = QEventPoint::State::Released;
+    QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
+    QCoreApplication::processEvents();
+    points.clear();
+    points.append(tp1);
+    points[0].state = QEventPoint::State::Released;
+    QWindowSystemInterface::handleTouchEvent(&window, touchDevice, points);
+    QCoreApplication::processEvents();
+    QTRY_COMPARE(window.mouseReleaseButton, 1);
 }
 
 void tst_QWindow::touchToMouseTranslationForDevices()