@Test
public void testIfThenElsePieceCount() {

  Piece piece1 = new Piece();
  Piece piece2 = new Piece();
  Block ifBlock = new IfBlock(
      TRUE_SUPPLIER,
      piece1,
      piece2
  );
  Assert.assertTrue(ifBlock.getPieceCount().isKnown());
  Assert.assertEquals(1, ifBlock.getPieceCount().getCount());
}