def test_event_marker(self):
        pv = self.pile_viewer
        self.add_one_pick()

        # select all markers
        QTest.keyPress(pv, 'a', Qt.ShiftModifier, 100)

        # convert to EventMarker
        QTest.keyPress(pv, 'e')

        QTest.keyPress(pv, 'd')

        for m in pv.viewer.get_markers():
            self.assertTrue(isinstance(m, gui_util.EventMarker))