'motions: lowercase mode is alpha, digit and _, uppercase is delim by spaces
b/B: backward short/long word'

def test_motion_backward(self):

    r = ViModeTest()
    r._set_line(u'abc_123        def--456.789        x')
    r.input(u'Escape')
    r.input(u'"$"')
    self.assertEqual(23, r.line_cursor)
    r.input(u'"b"')
    self.assertEqual(18, r.line_cursor)
    r.input(u'"b"')
    self.assertEqual(17, r.line_cursor)
    r.input(u'"B"')
    self.assertEqual(9, r.line_cursor)
    r.input(u'"B"')
    self.assertEqual(0, r.line_cursor)
