* Some code clean up and a new test.

Mage.Sets/src/mage/cards/d/DiamondKnight.java

@@ -15,11 +15,11 @@ import mage.constants.Outcome;
 import mage.constants.SubType;
 import mage.counters.CounterType;
 import mage.filter.FilterSpell;
-import mage.filter.predicate.ObjectPlayerPredicate;
 import mage.filter.predicate.ObjectSourcePlayer;
 import mage.game.Game;
 
 import java.util.UUID;
+import mage.filter.predicate.ObjectSourcePlayerPredicate;
 
 /**
  * @author TheElk801
@@ -59,7 +59,7 @@ public final class DiamondKnight extends CardImpl {
     }
 }
 
-enum DiamondKnightPredicate implements ObjectPlayerPredicate<ObjectSourcePlayer<MageObject>> {
+enum DiamondKnightPredicate implements ObjectSourcePlayerPredicate<ObjectSourcePlayer<MageObject>> {
     instance;
 
     @Override

Mage.Tests/src/test/java/org/mage/test/cards/triggers/SpellCastTriggerTest.java

@@ -119,4 +119,54 @@ public class SpellCastTriggerTest extends CardTestPlayerBase {
         assertHandCount(playerA, 5); // one normally drawn + 4 from Read the Bones
 
     }
+    
+    @Test
+    public void testDiamondKnightTrigger() {
+        addCard(Zone.BATTLEFIELD, playerA, "Volcanic Island", 6);
+
+        // Vigilance
+        // As Diamond Knight enters the battlefield, choose a color.
+        // Whenever you cast a spell of the chosen color, put a +1/+1 counter on Diamond Knight.        
+        addCard(Zone.HAND, playerA, "Diamond Knight", 1); // Creature 1/1 - {3}
+        
+        // Target 3 damage
+        addCard(Zone.HAND, playerA, "Lightning Bolt", 1); // {R}
+        // Draw a card.
+        // Escape—{2}{U}, Exile five other cards from your graveyard.
+        addCard(Zone.HAND, playerA, "Glimpse of Freedom", 1); // Instant {1}{U}
+        addCard(Zone.GRAVEYARD, playerA, "Mountain", 5); // Instant {1}{U}
+
+        castSpell(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Diamond Knight");      
+        setChoice(playerA, "Blue");
+
+        castSpell(1, PhaseStep.POSTCOMBAT_MAIN, playerA, "Lightning Bolt", playerB);
+        castSpell(1, PhaseStep.POSTCOMBAT_MAIN, playerA, "Glimpse of Freedom");
+        
+        castSpell(3, PhaseStep.PRECOMBAT_MAIN, playerA, "Glimpse of Freedom");
+        setChoice(playerA,"Mountain");
+        setChoice(playerA,"Mountain");
+        setChoice(playerA,"Mountain");
+        setChoice(playerA,"Mountain");
+        setChoice(playerA,"Mountain");
+        
+        
+
+        setStopAt(3, PhaseStep.BEGIN_COMBAT);
+        setStrictChooseMode(true);
+        execute();
+        assertAllCommandsUsed();
+
+        assertPermanentCount(playerA, "Diamond Knight", 1);
+        assertPowerToughness(playerA, "Diamond Knight", 3, 3);
+        assertGraveyardCount(playerA, "Lightning Bolt", 1);        
+        assertLife(playerB, 17);        
+        assertGraveyardCount(playerA, "Glimpse of Freedom", 1);
+        assertExileCount(playerA, 5);
+        assertHandCount(playerA, 3); 
+
+    }
+    
+    
+    
+    
 }

Mage.Tests/src/test/java/org/mage/test/serverside/base/impl/CardTestPlayerAPIImpl.java

@@ -1552,6 +1552,7 @@ public abstract class CardTestPlayerAPIImpl extends MageTestPlayerBase implement
     /**
      * For use choices set "Yes" or "No" the the choice string. For X values set
      * "X=[xValue]" example: for X=3 set choice string to "X=3".
+     * <br>For ColorChoice use "Red", "Green", "Blue", "Black" or "White"
      * 
      * @param player
      * @param choice

Mage/src/main/java/mage/filter/predicate/Predicates.java

@@ -195,7 +195,7 @@ public final class Predicates {
     }
 
     static <T> List<T> defensiveCopy(Iterable<T> iterable) {
-        ArrayList<T> list = new ArrayList<T>();
+        ArrayList<T> list = new ArrayList<>();
         for (T element : iterable) {
             list.add(checkNotNull(element));
         }

Mage/src/main/java/mage/filter/predicate/mageobject/ChosenSubtypePredicate.java

@@ -4,14 +4,14 @@ package mage.filter.predicate.mageobject;
 import mage.MageObject;
 import mage.abilities.effects.common.ChooseCreatureTypeEffect;
 import mage.constants.SubType;
-import mage.filter.predicate.ObjectPlayerPredicate;
 import mage.filter.predicate.ObjectSourcePlayer;
+import mage.filter.predicate.ObjectSourcePlayerPredicate;
 import mage.game.Game;
 
 /**
  * @author LoneFox
  */
-public enum ChosenSubtypePredicate implements ObjectPlayerPredicate<ObjectSourcePlayer<MageObject>> {
+public enum ChosenSubtypePredicate implements ObjectSourcePlayerPredicate<ObjectSourcePlayer<MageObject>> {
     instance;
 
     @Override