Fix Nahiri, Forged in Fury trigger (#13893)

Fixes the trigger firing for all attacking creatures, not just equipped
ones.

Restores the equipped predicate removed in commit db193bd4 (#13707) and
adds tests to prevent future regressions.

Mage.Sets/src/mage/cards/n/NahiriForgedInFury.java

@@ -11,6 +11,7 @@ import mage.cards.CardImpl;
 import mage.cards.CardSetInfo;
 import mage.constants.*;
 import mage.filter.common.FilterControlledCreaturePermanent;
+import mage.filter.predicate.permanent.EquippedPredicate;
 import mage.game.Game;
 import mage.players.Player;
 
@@ -24,6 +25,10 @@ public final class NahiriForgedInFury extends CardImpl {
     private static final FilterControlledCreaturePermanent equippedFilter = new FilterControlledCreaturePermanent(
             "an equipped creature you control");
 
+    static {
+        equippedFilter.add(EquippedPredicate.instance);
+    }
+
     public NahiriForgedInFury(UUID ownerId, CardSetInfo setInfo) {
         super(ownerId, setInfo, new CardType[]{CardType.CREATURE}, "{4}{R}{W}");
 

Mage.Tests/src/test/java/org/mage/test/cards/single/mat/NahiriForgedInFuryTest.java

@@ -0,0 +1,98 @@
+package org.mage.test.cards.single.mat;
+
+import mage.constants.PhaseStep;
+import mage.constants.Zone;
+import org.junit.Test;
+import org.mage.test.serverside.base.CardTestPlayerBase;
+
+
+/**
+ * @author correl
+ */
+public class NahiriForgedInFuryTest extends CardTestPlayerBase {
+
+    /**
+     * {@link mage.cards.n.NahiriForgedInFury} {4}{R}{W}
+     * Legendary Creature - Kor Artificer
+     *
+     * Affinity for Equipment
+     *
+     * Whenever an equipped creature you control attacks, exile the top card of
+     * your library. You may play that card this turn. You may cast Equipment
+     * spells this way without paying their mana costs.
+     */
+    private static final String nahiri = "Nahiri, Forged in Fury";
+
+    private final String boots = "Swiftfoot Boots";
+    private final String cleaver = "The Reaver Cleaver";
+    private final String giant = "Hill Giant";
+    private final String greaves = "Lightning Greaves";
+    private final String lions = "Savannah Lions";
+    private final String sword = "Sword of Feast and Famine";
+
+    @Test
+    public void test_CostReducedByEquipment() {
+        // Nahiri in hand, four equipment in play, and enough to pay RW
+        addCard(Zone.HAND, playerA, nahiri);
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 1);
+        addCard(Zone.BATTLEFIELD, playerA, "Plains", 1);
+        addCard(Zone.BATTLEFIELD, playerA, boots);
+        addCard(Zone.BATTLEFIELD, playerA, cleaver);
+        addCard(Zone.BATTLEFIELD, playerA, greaves);
+        addCard(Zone.BATTLEFIELD, playerA, sword);
+
+        // Cast for RW (Reduced by 4)
+        castSpell(1, PhaseStep.PRECOMBAT_MAIN, playerA, nahiri);
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        execute();
+    }
+
+    @Test
+    public void test_EquippedAttackTriggers() {
+        addCard(Zone.BATTLEFIELD, playerA, "Mountain", 1);
+        addCard(Zone.BATTLEFIELD, playerA, nahiri);
+        addCard(Zone.BATTLEFIELD, playerA, lions);
+        addCard(Zone.BATTLEFIELD, playerA, giant);
+        addCard(Zone.BATTLEFIELD, playerA, boots);
+        addCard(Zone.BATTLEFIELD, playerA, greaves);
+        activateAbility(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Equip {0}", lions);
+        waitStackResolved(1, PhaseStep.PRECOMBAT_MAIN);
+        activateAbility(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Equip {1}", giant);
+
+        // Attack with three creatures, two of which are equipped
+        attack(1, playerA, nahiri);
+        attack(1, playerA, lions);
+        attack(1, playerA, giant);
+
+        // Order the 2 Nahiri triggers
+        setChoice(playerA, "Whenever an equipped creature you control attacks");
+
+        setStrictChooseMode(true);
+        setStopAt(1, PhaseStep.END_TURN);
+        execute();
+
+        // Triggered twice, exiling two cards
+        assertExileCount(playerA, 2);
+    }
+
+    @Test
+    public void test_CanCastExiledEquipmentForFree() {
+        addCard(Zone.BATTLEFIELD, playerA, nahiri);
+        addCard(Zone.BATTLEFIELD, playerA, greaves);
+        skipInitShuffling();
+        addCard(Zone.LIBRARY, playerA, sword);
+        activateAbility(1, PhaseStep.PRECOMBAT_MAIN, playerA, "Equip {0}", nahiri);
+
+        // Attack with one equipped creature, exiling the sword
+        attack(1, playerA, nahiri);
+
+        // Cast sword for free
+        castSpell(1, PhaseStep.POSTCOMBAT_MAIN, playerA, sword);
+
+        setStrictChooseMode(true);
+        setStopAt(2, PhaseStep.END_TURN);
+        execute();
+    }
+}