import org.junit.jupiter.api.Disabled; import org.junit.jupiter.api.DisplayName; import org.junit.jupiter.api.Test; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; import static org.assertj.core.api.Assertions.assertThat; import static org.assertj.core.api.Assertions.assertThatExceptionOfType; public class DominoesTest { @Test @DisplayName("empty input = empty output") public void emtpyInputEmptyOutputTest() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); List dominoesList = new ArrayList<>(); List chain = dominoes.formChain(dominoesList); assertThat(chain).withFailMessage("The output list should be empty.").hasSize(0); } @Disabled("Remove to run test") @Test @DisplayName("singleton input = singleton output") public void singletonInputSingletonOutput() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 1)}; List dominoesList = Arrays.asList(dominoesArray); List chain = dominoes.formChain(dominoesList); assertValidChain(dominoesList, chain); } @Disabled("Remove to run test") @Test @DisplayName("singleton that can't be chained") public void singletonCantBeChainedTest() { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2)}; List dominoesList = Arrays.asList(dominoesArray); assertThatExceptionOfType(ChainNotFoundException.class) .isThrownBy(() -> dominoes.formChain(dominoesList)) .withMessage("No domino chain found."); } @Disabled("Remove to run test") @Test @DisplayName("three elements") public void threeElementsTest() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(3, 1), new Domino(2, 3)}; List dominoesList = Arrays.asList(dominoesArray); List chain = dominoes.formChain(dominoesList); assertValidChain(dominoesList, chain); } @Disabled("Remove to run test") @Test @DisplayName("can reverse dominoes") public void canReverseDominoesTest() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(1, 3), new Domino(2, 3)}; List dominoesList = Arrays.asList(dominoesArray); List chain = dominoes.formChain(dominoesList); assertValidChain(dominoesList, chain); } @Disabled("Remove to run test") @Test @DisplayName("can't be chained") public void cantBeChainedTest() { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(4, 1), new Domino(2, 3)}; List dominoesList = Arrays.asList(dominoesArray); assertThatExceptionOfType(ChainNotFoundException.class) .isThrownBy(() -> dominoes.formChain(dominoesList)) .withMessage("No domino chain found."); } @Disabled("Remove to run test") @Test @DisplayName("disconnected - simple") public void disconnectedSimpleTest() { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 1), new Domino(2, 2)}; List dominoesList = Arrays.asList(dominoesArray); assertThatExceptionOfType(ChainNotFoundException.class) .isThrownBy(() -> dominoes.formChain(dominoesList)) .withMessage("No domino chain found."); } @Disabled("Remove to run test") @Test @DisplayName("disconnected - double loop") public void disconnectedDoubleLoopTest() { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(2, 1), new Domino(3, 4), new Domino(4, 3)}; List dominoesList = Arrays.asList(dominoesArray); assertThatExceptionOfType(ChainNotFoundException.class) .isThrownBy(() -> dominoes.formChain(dominoesList)) .withMessage("No domino chain found."); } @Disabled("Remove to run test") @Test @DisplayName("disconnected - single isolated") public void disconnectedSingleIsolatedTest() { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(2, 3), new Domino(3, 1), new Domino(4, 4)}; List dominoesList = Arrays.asList(dominoesArray); assertThatExceptionOfType(ChainNotFoundException.class) .isThrownBy(() -> dominoes.formChain(dominoesList)) .withMessage("No domino chain found."); } @Disabled("Remove to run test") @Test @DisplayName("need backtrack") public void needBacktrackTest() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(2, 3), new Domino(3, 1), new Domino(2, 4), new Domino(4, 2)}; List dominoesList = Arrays.asList(dominoesArray); List chain = dominoes.formChain(dominoesList); assertValidChain(dominoesList, chain); } @Disabled("Remove to run test") @Test @DisplayName("separate loops") public void separateLoopsTest() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(2, 3), new Domino(3, 1), new Domino(1, 1), new Domino(2, 2), new Domino(3, 3)}; List dominoesList = Arrays.asList(dominoesArray); List chain = dominoes.formChain(dominoesList); assertValidChain(dominoesList, chain); } @Disabled("Remove to run test") @Test @DisplayName("nine elements") public void nineElementsTest() throws ChainNotFoundException { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(5, 3), new Domino(3, 1), new Domino(1, 2), new Domino(2, 4), new Domino(1, 6), new Domino(2, 3), new Domino(3, 4), new Domino(5, 6)}; List dominoesList = Arrays.asList(dominoesArray); List chain = dominoes.formChain(dominoesList); assertValidChain(dominoesList, chain); } @Disabled("Remove to run test") @Test @DisplayName("separate three-domino loops") public void separateThreeDominoLoopsTest() { Dominoes dominoes = new Dominoes(); Domino[] dominoesArray = {new Domino(1, 2), new Domino(2, 3), new Domino(3, 1), new Domino(4, 5), new Domino(5, 6), new Domino (6, 4)}; List dominoesList = Arrays.asList(dominoesArray); assertThatExceptionOfType(ChainNotFoundException.class) .isThrownBy(() -> dominoes.formChain(dominoesList)) .withMessage("No domino chain found."); } private void assertValidChain(List inputDominoes, List outputDominoes) { assertSameDominoes(inputDominoes, outputDominoes); assertEndDominoesMatch(outputDominoes); assertConsecutiveDominoes(outputDominoes); } private void assertEndDominoesMatch(List outputDominoes) { int leftValueOfFirstDomino = outputDominoes.get(0).getLeft(); int rightValueOfLastDomino = outputDominoes.get(outputDominoes.size() - 1).getRight(); String errorMessage = "The left value of the first domino (" + leftValueOfFirstDomino + ") needs to match the right value of the last domino (" + rightValueOfLastDomino + ")."; assertThat(leftValueOfFirstDomino).withFailMessage(errorMessage).isEqualTo(rightValueOfLastDomino); } private void assertSameDominoes(List inputDominoes, List outputDominoes) { String errorMessage = "The number of dominoes in the input list (" + inputDominoes.size() + ") needs to match the number of dominoes in the output chain (" + outputDominoes.size() + ")"; assertThat(inputDominoes).withFailMessage(errorMessage).hasSameSizeAs(outputDominoes); for (Domino domino : inputDominoes) { int inputFrequency = Collections.frequency(inputDominoes, domino); int outputFrequency = Collections.frequency(outputDominoes, domino); String frequencyErrorMessage = "The frequency of domino (" + domino.getLeft() + ", " + domino.getRight() + ")" + " in the input is (" + inputFrequency + "), but (" + outputFrequency + ") in the output."; assertThat(inputFrequency).withFailMessage(frequencyErrorMessage).isEqualTo(outputFrequency); } } private void assertConsecutiveDominoes(List dominoes) { for (int i = 0; i < dominoes.size() - 1; i++) { int rightValueOfIthDomino = dominoes.get(i).getRight(); int leftValueOfNextDomino = dominoes.get(i + 1).getLeft(); String errorMessage = "The right value of domino number " + i + " (" + rightValueOfIthDomino + ") needs to match the left value of domino number " + (i + 1) + " (" + leftValueOfNextDomino + ")."; assertThat(dominoes.get(i).getRight()).withFailMessage(errorMessage) .isEqualTo(dominoes.get(i + 1).getLeft()); } } }