@Test
 public void canDoXorOperation() {
   viewModel.setOperation(Operation.XOR);
   initArraysForOperations();
   viewModel.doOperation();
   assertNotNull(viewModel.getResultBitArray());
 }
  @Test
  public void canDoOrOperation() {
    initArraysForOperations();

    viewModel.doOperation();

    assertNotNull(viewModel.getResultBitArray());
  }
  @Test
  public void isResultBitArraySizeEquals5WhenInputSize5() {
    viewModel.setArraySize("5");

    viewModel.initializeArray();

    assertEquals(viewModel.getResultBitArray().getSize(), 5);
  }