Velocities reported by Flickable in onFlickStarted can be 0

Ensure the smoothed velocity is set at the start of the flick.  Ensure
that the smoothed velocity animation isn't restarted unless there is
new valid data.

Change-Id: I00f8bbf1fe91faeea752b093c4658ad0f53ad06d
Task-number: QTBUG-19676
Reviewed-by: Bea Lam
(cherry picked from commit a2d97672bfaace677a4308db93f5802ba53af46e)

1 files changed, 69 insertions, 0 deletions

diff --git a/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp b/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp
index b077fdc..31a6b10 100644
--- a/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp
+++ b/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp
@@ -78,6 +78,7 @@ private slots:
     void testQtQuick11Attributes();
     void testQtQuick11Attributes_data();
     void wheel();
+    void flickVelocity();
 
 private:
     QDeclarativeEngine engine;
@@ -480,6 +481,74 @@ void tst_qdeclarativeflickable::wheel()
     delete canvas;
 }
 
+void tst_qdeclarativeflickable::flickVelocity()
+{
+    QDeclarativeView *canvas = new QDeclarativeView;
+    canvas->setSource(QUrl::fromLocalFile(SRCDIR "/data/flickable03.qml"));
+    canvas->show();
+    canvas->setFocus();
+    QVERIFY(canvas->rootObject() != 0);
+
+    QDeclarativeFlickable *flickable = qobject_cast<QDeclarativeFlickable*>(canvas->rootObject());
+    QVERIFY(flickable != 0);
+
+    QTest::mousePress(canvas->viewport(), Qt::LeftButton, 0, canvas->mapFromScene(QPoint(20, 90)));
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,80)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,70)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,60)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,50)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+
+    QTest::mouseRelease(canvas->viewport(), Qt::LeftButton, 0, canvas->mapFromScene(QPoint(20, 50)));
+
+    QVERIFY(flickable->verticalVelocity() > 0.0);
+    QTRY_VERIFY(flickable->verticalVelocity() == 0.0);
+
+    QTest::mousePress(canvas->viewport(), Qt::LeftButton, 0, canvas->mapFromScene(QPoint(20, 10)));
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,20)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,30)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,40)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+    {
+        QMouseEvent mv(QEvent::MouseMove, canvas->mapFromScene(QPoint(20,50)), Qt::LeftButton, Qt::LeftButton,Qt::NoModifier);
+        QApplication::sendEvent(canvas->viewport(), &mv);
+    }
+    QTest::qWait(10);
+
+    QTest::mouseRelease(canvas->viewport(), Qt::LeftButton, 0, canvas->mapFromScene(QPoint(20, 50)));
+
+    QVERIFY(flickable->verticalVelocity() < 0.0);
+    QTRY_VERIFY(flickable->verticalVelocity() == 0.0);
+
+    delete canvas;
+}
+
 
 template<typename T>
 T *tst_qdeclarativeflickable::findItem(QGraphicsObject *parent, const QString &objectName)