Non-beaten candidates are winners #246 (#314)

* Non-beaten andidates are winners #246

src/main/java/org/rulez/demokracia/pdengine/ComputedVote.java

@@ -68,7 +68,7 @@ private BeatTable ignoreChoices(final List<String> ignoredChoices) {
 		BeatTable filteredBeatTable = new BeatTable(activeChoices);
 		for (String key1 : activeChoices) {
 			for (String key2 : activeChoices) {
-				Pair source = beatTable.getElement(key1, key2);
+				Pair source = beatPathTable.getElement(key1, key2);
 				if (Objects.nonNull(source))
 					filteredBeatTable.setElement(key1, key2, source);
 			}

src/main/java/org/rulez/demokracia/pdengine/Normalizable.java

@@ -10,16 +10,16 @@ public interface Normalizable extends ContainingBeats {
 
 	default void normalize() {
 		Collection<String> keys = getKeyCollection();
-		
+
 		for (String key1 : keys) {
 			for (String key2 : keys) {
 				Pair beats1 = getPair(key1, key2);
 				Pair beats2 = getPair(key2, key1);
 				Pair pair = compareBeats(beats1, beats2);
-				
-				if(pair.equals(beats1))
+
+				if (pair.equals(beats1))
 					setElement(key2, key1, new Pair(0, 0));
-				if(pair.equals(beats2))
+				if (pair.equals(beats2))
 					setElement(key1, key2, new Pair(0, 0));
 			}
 		}

src/main/java/org/rulez/demokracia/pdengine/WinnerCalculatorImpl.java

@@ -1,12 +1,26 @@
 package org.rulez.demokracia.pdengine;
 
 import java.util.List;
+import java.util.stream.Collectors;
+
+import org.rulez.demokracia.pdengine.dataobjects.Pair;
 
 public class WinnerCalculatorImpl implements WinnerCalculator {
 
 	@Override
 	public List<String> calculateWinners(final BeatTable beatTable) {
-		throw new UnsupportedOperationException();
+		return beatTable.getKeyCollection()
+				.stream()
+				.filter(choice -> isWinner(choice, beatTable))
+				.collect(Collectors.toList());
+	}
+
+	private boolean isWinner(final String choice, final BeatTable beatTable) {
+		Pair nonbeatingPair = new Pair(0, 0);
+
+		return beatTable.getKeyCollection()
+				.stream()
+				.allMatch(otherChoice -> nonbeatingPair.equals(beatTable.getElement(otherChoice, choice)));
 	}
 
 }

src/test/java/org/rulez/demokracia/pdengine/CalculateWinnersTest.java

@@ -1,44 +1,34 @@
 package org.rulez.demokracia.pdengine;
 
 import static org.junit.Assert.*;
-import static org.mockito.Mockito.*;
-
 import java.util.Arrays;
 import java.util.List;
-import java.util.stream.Collectors;
-
 import org.junit.Before;
 import org.junit.Test;
-import org.mockito.ArgumentCaptor;
-import org.mockito.stubbing.Answer;
 import org.rulez.demokracia.pdengine.annotations.TestedBehaviour;
 import org.rulez.demokracia.pdengine.annotations.TestedFeature;
 import org.rulez.demokracia.pdengine.annotations.TestedOperation;
+import org.rulez.demokracia.pdengine.dataobjects.Pair;
 import org.rulez.demokracia.pdengine.testhelpers.CreatedDefaultCastVoteWithRankedChoices;
 
 @TestedFeature("Vote")
 @TestedOperation("calculate winners")
 public class CalculateWinnersTest extends CreatedDefaultCastVoteWithRankedChoices {
 
-	private final Answer<?> answerKeyCollection = (invocation) -> {
-		BeatTable beatTable = (BeatTable) invocation.getArguments()[0];
-		return beatTable.getKeyCollection().stream().collect(Collectors.toList());
-	};
-
 	private ComputedVote computedVote;
-	private final ArgumentCaptor<BeatTable> captor = ArgumentCaptor.forClass(BeatTable.class);
+	private WinnerCalculator winnerCalculator;
+	private BeatTable beatPathTable;
 
 	@Override
 	@Before
 	public void setUp() {
 		super.setUp();
 		getTheVote().votesCast = castVote;
-		WinnerCalculatorImpl winnerCalculator = mock(WinnerCalculatorImpl.class);
-		when(winnerCalculator.calculateWinners(captor.capture())).thenAnswer(answerKeyCollection);
 
 		computedVote = new ComputedVote(getTheVote());
 		computedVote.computeVote();
-		computedVote.setWinnerCalculator(winnerCalculator);
+		winnerCalculator = new WinnerCalculatorImpl();
+		beatPathTable = computedVote.getBeatPathTable();
 	}
 
 	@TestedBehaviour("only choices not in ignoredChoices are considered")
@@ -53,14 +43,40 @@ public void calculate_winners_returns_none_of_the_ignored_choices() {
 	@Test
 	public void calculate_winners_returns_not_ignored_winner() {
 		List<String> winners = computedVote.calculateWinners(Arrays.asList("C"));
-		assertBeatTableContainChoice(winners, "A");
+		assertTrue(winners.contains("D"));
+	}
+
+	@TestedBehaviour("all non-beaten candidates are winners")
+	@Test
+	public void calculate_winners_doesnt_return_beaten_candidates() {
+		assertNoWinnerIsBeaten(winnerCalculator.calculateWinners(beatPathTable));
 	}
 
-	private void assertBeatTableContainChoice(final List<String> winners, final String choice) {
-		assertTrue(winners.contains(choice));
-		BeatTable capturedBeatTable = captor.getValue();
-		assertNotNull(capturedBeatTable.getElement(choice, "B"));
+	@TestedBehaviour("all non-beaten candidates are winners")
+	@Test
+	public void calculate_winners_return_all_non_beaten_candidates() {
+		assertNonbeatensAreWinner(winnerCalculator.calculateWinners(beatPathTable));
+	}
+
+	private void assertNoWinnerIsBeaten(final List<String> winners) {
+		assertTrue(winners.stream().allMatch(choice -> isAWinner(choice, beatPathTable)));
 	}
 
+	private void assertNonbeatensAreWinner(final List<String> winners) {
+		assertTrue(beatPathTable.getKeyCollection()
+				.stream()
+				.filter(choice -> isAWinner(choice, beatPathTable))
+				.allMatch(choice -> winners.contains(choice)));
+	}
+
+	private boolean isAWinner(final String player1, final BeatTable beatPathTable) {
+		for (String player2 : beatPathTable.getKeyCollection()) {
+			Pair forward = beatPathTable.getElement(player1, player2);
+			Pair backward = beatPathTable.getElement(player2, player1);
+			if (!forward.equals(beatPathTable.compareBeats(forward, backward)))
+				return false;
+		}
+		return true;
+	}
 
 }

src/test/java/org/rulez/demokracia/pdengine/UnimplementedTests.java

@@ -16,9 +16,4 @@ public class UnimplementedTests extends ThrowableTester {
 	public void the_getAssurances_method_is_not_implemented_yet() {
 		assertUnimplemented(() -> new CastVote("proxyId", new ArrayList<>()).getAssurances());
 	}
-
-	@Test
-	public void the_calculateWinners_method_is_not_implemented_yet() {
-		assertUnimplemented(() -> new WinnerCalculatorImpl().calculateWinners(null));
-	}
 }