[PIP] Implement Sentinel Sarah Lyons; The Prydwen, Steel Flagship; add common watcher + condition (#12250)

* [PIP] Implement Sentinel Sarah Lyons

* Create common watcher and condition for artifacts entering

* [PIP] Implement The Prydwen, Steel Flagship

* Use common classes in Akal Pakal, First Among Equals; string correction

* Add warning about watcher to ArtifactEnteredUnderYourControlCondition

* Add tests

* Move test file

* Test with opponent casting artifact during your turn

* Use checkPT(), don't call execute() multiple times

* Check final assertion at upkeep instead of untap step

Mage/src/main/java/mage/abilities/condition/common/ArtifactEnteredUnderYourControlCondition.java

@@ -0,0 +1,25 @@
+package mage.abilities.condition.common;
+
+import mage.abilities.Ability;
+import mage.abilities.condition.Condition;
+import mage.game.Game;
+import mage.watchers.common.ArtifactEnteredControllerWatcher;
+
+/**
+ * /!\ You need to add ArtifactEnteredControllerWatcher to any card using this condition
+ *
+ * @author Cguy7777
+ */
+public enum ArtifactEnteredUnderYourControlCondition implements Condition {
+    instance;
+
+    @Override
+    public boolean apply(Game game, Ability source) {
+        return ArtifactEnteredControllerWatcher.enteredArtifactForPlayer(source.getControllerId(), game);
+    }
+
+    @Override
+    public String toString() {
+        return "an artifact entered the battlefield under your control this turn";
+    }
+}

Mage/src/main/java/mage/game/permanent/token/ThePrydwenSteelFlagshipHumanKnightToken.java

@@ -0,0 +1,45 @@
+package mage.game.permanent.token;
+
+import mage.MageInt;
+import mage.abilities.common.SimpleStaticAbility;
+import mage.abilities.condition.common.ArtifactEnteredUnderYourControlCondition;
+import mage.abilities.decorator.ConditionalContinuousEffect;
+import mage.abilities.effects.common.continuous.BoostSourceEffect;
+import mage.abilities.hint.ConditionHint;
+import mage.constants.CardType;
+import mage.constants.Duration;
+import mage.constants.SubType;
+
+/**
+ * @author Cguy7777
+ */
+public class ThePrydwenSteelFlagshipHumanKnightToken extends TokenImpl {
+
+    /**
+     * /!\ You need to add ArtifactEnteredControllerWatcher to any card using this token
+     */
+    public ThePrydwenSteelFlagshipHumanKnightToken() {
+        super("Human Knight Token", "2/2 white Human Knight creature token with \"This creature " +
+                "gets +2/+2 as long as an artifact entered the battlefield under your control this turn.\"");
+        cardType.add(CardType.CREATURE);
+        color.setWhite(true);
+        subtype.add(SubType.HUMAN, SubType.KNIGHT);
+        power = new MageInt(2);
+        toughness = new MageInt(2);
+
+        this.addAbility(new SimpleStaticAbility(new ConditionalContinuousEffect(
+                new BoostSourceEffect(2, 2, Duration.WhileOnBattlefield),
+                ArtifactEnteredUnderYourControlCondition.instance,
+                "This creature gets +2/+2 as long as an artifact entered the battlefield under your control this turn"))
+                .addHint(new ConditionHint(ArtifactEnteredUnderYourControlCondition.instance)));
+    }
+
+    private ThePrydwenSteelFlagshipHumanKnightToken(final ThePrydwenSteelFlagshipHumanKnightToken token) {
+        super(token);
+    }
+
+    @Override
+    public ThePrydwenSteelFlagshipHumanKnightToken copy() {
+        return new ThePrydwenSteelFlagshipHumanKnightToken(this);
+    }
+}

Mage/src/main/java/mage/watchers/common/ArtifactEnteredControllerWatcher.java

@@ -0,0 +1,49 @@
+package mage.watchers.common;
+
+import mage.constants.WatcherScope;
+import mage.game.Game;
+import mage.game.events.EntersTheBattlefieldEvent;
+import mage.game.events.GameEvent;
+import mage.watchers.Watcher;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.UUID;
+
+/**
+ * @author Cguy7777
+ */
+public class ArtifactEnteredControllerWatcher extends Watcher {
+
+    private final Set<UUID> players = new HashSet<>();
+
+    public ArtifactEnteredControllerWatcher() {
+        super(WatcherScope.GAME);
+    }
+
+    @Override
+    public void watch(GameEvent event, Game game) {
+        if (event.getType() != GameEvent.EventType.ENTERS_THE_BATTLEFIELD) {
+            return;
+        }
+
+        EntersTheBattlefieldEvent eEvent = (EntersTheBattlefieldEvent) event;
+        if (eEvent.getTarget() != null && eEvent.getTarget().isArtifact(game)) {
+            players.add(eEvent.getTarget().getControllerId());
+        }
+    }
+
+    @Override
+    public void reset() {
+        super.reset();
+        players.clear();
+    }
+
+    public static boolean enteredArtifactForPlayer(UUID playerId, Game game) {
+        return game
+                .getState()
+                .getWatcher(ArtifactEnteredControllerWatcher.class)
+                .players
+                .contains(playerId);
+    }
+}