public void testComputeSize() {
   Fixture.fakePhase(PhaseId.PROCESS_ACTION);
   Display display = new Display();
   Composite shell = new Shell(display, SWT.NONE);
   Twistie twistie = new Twistie(shell, SWT.NONE);
   Point expected = new Point(11, 11);
   assertEquals(expected, twistie.computeSize(SWT.DEFAULT, SWT.DEFAULT));
   // fixed size
   expected = new Point(11, 11);
   assertEquals(expected, twistie.computeSize(50, 50));
 }