### Question:
DiamondPrinter { List<String> printToList(char a) { throw new UnsupportedOperationException("Delete this statement and write your own implementation."); }    }### Answer:
@Test public void testOneByOneDiamond() { assertThat(diamondPrinter.printToList('A')) .containsExactly("A"); }
@Ignore("Remove to run test") @Test public void testTwoByTwoDiamond() { assertThat(diamondPrinter.printToList('B')) .containsExactly( " A ", "B B", " A "); }
@Ignore("Remove to run test") @Test public void testThreeByThreeDiamond() { assertThat(diamondPrinter.printToList('C')) .containsExactly( " A ", " B B ", "C C", " B B ", " A "); }
@Ignore("Remove to run test") @Test public void testFourByFourDiamond() { assertThat(diamondPrinter.printToList('D')) .containsExactly( " A ", " B B ", " C C ", "D D", " C C ", " B B ", " A "); }
@Ignore("Remove to run test") @Test public void testFullDiamond() { assertThat(diamondPrinter.printToList('Z')) .containsExactly( " A ", " B B ", " C C ", " D D ", " E E ", " F F ", " G G ", " H H ", " I I ", " J J ", " K K ", " L L ", " M M ", " N N ", " O O ", " P P ", " Q Q ", " R R ", " S S ", " T T ", " U U ", " V V ", " W W ", " X X ", " Y Y ", "Z Z", " Y Y ", " X X ", " W W ", " V V ", " U U ", " T T ", " S S ", " R R ", " Q Q ", " P P ", " O O ", " N N ", " M M ", " L L ", " K K ", " J J ", " I I ", " H H ", " G G ", " F F ", " E E ", " D D ", " C C ", " B B ", " A "); }