diff --git a/app/src/main/java/chess/ai/DumbAI.java b/app/src/main/java/chess/ai/DumbAI.java
index 9396c3e..c1ea82f 100644
--- a/app/src/main/java/chess/ai/DumbAI.java
+++ b/app/src/main/java/chess/ai/DumbAI.java
@@ -31,7 +31,7 @@ public class DumbAI extends AI {
 				int randomMove = this.random.nextInt(moves.size() + 2);
 				if (randomMove < moves.size() - 2)
 					break;
-				this.commandExecutor.executeCommand(new CastlingCommand(randomMove == moves.size()));
+				sendCommand(new CastlingCommand(randomMove == moves.size()));
 				return;
 			}
 
@@ -40,7 +40,7 @@ public class DumbAI extends AI {
 				int randomMove = this.random.nextInt(moves.size() + 1);
 				if (randomMove != moves.size())
 					break;
-				this.commandExecutor.executeCommand(new CastlingCommand(castlings == CastlingResult.Big));
+				sendCommand(new CastlingCommand(castlings == CastlingResult.Big));
 				return;
 			}
 
@@ -49,13 +49,13 @@ public class DumbAI extends AI {
 		}
 
 		int randomMove = this.random.nextInt(moves.size());
-		this.commandExecutor.executeCommand(new MoveCommand(moves.get(randomMove)));
+		sendCommand(new MoveCommand(moves.get(randomMove)));
 	}
 
 	@Override
 	protected void promote(Coordinate pawnCoords) {
 		int promote = this.random.nextInt(PromoteType.values().length);
-		this.commandExecutor.executeCommand(new PromoteCommand(PromoteType.values()[promote]));
+		sendCommand(new PromoteCommand(PromoteType.values()[promote]));
 	}
 
 }
diff --git a/app/src/main/java/chess/controller/commands/PromoteCommand.java b/app/src/main/java/chess/controller/commands/PromoteCommand.java
index c3e51da..5eddd20 100644
--- a/app/src/main/java/chess/controller/commands/PromoteCommand.java
+++ b/app/src/main/java/chess/controller/commands/PromoteCommand.java
@@ -28,6 +28,7 @@ public class PromoteCommand extends PlayerCommand {
 
 	public PromoteCommand(PromoteType promoteType) {
 		this.promoteType = promoteType;
+		assert this.promoteType != null;
 		this.pieceCoords = null;
 		this.oldPawn = null;
 	}
diff --git a/app/src/test/java/chess/AppTest.java b/app/src/test/java/chess/AppTest.java
index e734791..46a4ecb 100644
--- a/app/src/test/java/chess/AppTest.java
+++ b/app/src/test/java/chess/AppTest.java
@@ -15,7 +15,7 @@ import chess.model.Color;
 import chess.model.Game;
 
 class AppTest {
-    @Test void functionalRollback(){
+    private void functionalRollback(){
         Game game = new Game();
         CommandExecutor commandExecutor = new CommandExecutor(game);
 
@@ -37,6 +37,9 @@ class AppTest {
                 Game initialGame = new Game();
                 CommandExecutor initialCommandExecutor = new CommandExecutor(initialGame);
                 initialCommandExecutor.executeCommand(new NewGameCommand());
+                
+                initialCommandExecutor.close();
+                commandExecutor.close();
 
                 assert(game.getBoard().equals(initialGame.getBoard()));