Fix switch-in abilities activating on empty field

include/battle.h

@@ -644,6 +644,7 @@ struct BattleStruct
     struct StolenItem itemStolen[PARTY_SIZE];  // Player's team that had items stolen (two bytes per party member)
     u8 blunderPolicy:1; // should blunder policy activate
     u8 swapDamageCategory:1; // Photon Geyser, Shell Side Arm, Light That Burns the Sky
+    u8 switchInAbilityPostponed:4; // To not activate against an empty field, each bit for battler
     u8 ballSpriteIds[2];    // item gfx, window gfx
     u8 stickyWebUser;
     u8 appearedInBattle; // Bitfield to track which Pokemon appeared in battle. Used for Burmy's form change

include/battle_script_commands.h

@@ -44,6 +44,7 @@ u16 GetSecretPowerMoveEffect(void);
 void StealTargetItem(u8 battlerStealer, u8 battlerItem);
 u8 GetCatchingBattler(void);
 u32 GetHighestStatId(u32 battlerId);
+bool32 DoSwitchInAbilitiesItems(u32 battlerId);
 
 extern void (* const gBattleScriptingCommandsTable[])(void);
 extern const u8 gBattlePalaceNatureToMoveGroupLikelihood[NUM_NATURES][4];

src/battle_script_commands.c

@@ -6900,6 +6900,35 @@ static void SetDmgHazardsBattlescript(u8 battlerId, u8 multistringId)
         gBattlescriptCurrInstr = BattleScript_DmgHazardsOnFaintedBattler;
 }
 
+bool32 DoSwitchInAbilitiesItems(u32 battlerId)
+{
+    return (AbilityBattleEffects(ABILITYEFFECT_ON_SWITCHIN, battlerId, 0, 0, 0)
+             || (gBattleWeather & B_WEATHER_ANY && WEATHER_HAS_EFFECT && AbilityBattleEffects(ABILITYEFFECT_ON_WEATHER, battlerId, 0, 0, 0))
+             || (gFieldStatuses & STATUS_FIELD_TERRAIN_ANY && AbilityBattleEffects(ABILITYEFFECT_ON_TERRAIN, battlerId, 0, 0, 0))
+             || ItemBattleEffects(ITEMEFFECT_ON_SWITCH_IN, battlerId, FALSE)
+             || AbilityBattleEffects(ABILITYEFFECT_TRACE2, 0, 0, 0, 0));
+}
+
+bool32 ShouldPostponeSwitchInAbilities(u32 battlerId)
+{
+    bool32 aliveOpposing1 = IsBattlerAlive(BATTLE_OPPOSITE(battlerId));
+    bool32 aliveOpposing2 = IsBattlerAlive(BATTLE_PARTNER(BATTLE_OPPOSITE(battlerId)));
+    // No pokemon on opposing side - postopone.
+    if (!aliveOpposing1 && !aliveOpposing2)
+        return TRUE;
+
+    // Checks for double battle, so abilities like Intimidate wait until all battlers are switched-in before activating.
+    if (IsDoubleBattle())
+    {
+        if (aliveOpposing1 && !aliveOpposing2 && !HasNoMonsToSwitch(BATTLE_OPPOSITE(battlerId), PARTY_SIZE, PARTY_SIZE))
+            return TRUE;
+        if (!aliveOpposing1 && aliveOpposing2 && !HasNoMonsToSwitch(BATTLE_PARTNER(BATTLE_OPPOSITE(battlerId)), PARTY_SIZE, PARTY_SIZE))
+            return TRUE;
+    }
+
+    return FALSE;
+}
+
 static void Cmd_switchineffects(void)
 {
     CMD_ARGS(u8 battler);
@@ -7016,12 +7045,17 @@ static void Cmd_switchineffects(void)
 
         gDisableStructs[gActiveBattler].truantSwitchInHack = 0;
 
-        if (AbilityBattleEffects(ABILITYEFFECT_ON_SWITCHIN, gActiveBattler, 0, 0, 0)
+        // Don't activate switch-in abilities if the opposing field is empty.
-         || (gBattleWeather & B_WEATHER_ANY && WEATHER_HAS_EFFECT && AbilityBattleEffects(ABILITYEFFECT_ON_WEATHER, gActiveBattler, 0, 0, 0))
+        // This could happen when a mon uses explosion and causes everyone to faint.
-         || (gFieldStatuses & STATUS_FIELD_TERRAIN_ANY && AbilityBattleEffects(ABILITYEFFECT_ON_TERRAIN, gActiveBattler, 0, 0, 0))
+        if (ShouldPostponeSwitchInAbilities(gActiveBattler) || gBattleStruct->switchInAbilityPostponed)
-         || ItemBattleEffects(ITEMEFFECT_ON_SWITCH_IN, gActiveBattler, FALSE)
+        {
-         || AbilityBattleEffects(ABILITYEFFECT_TRACE2, 0, 0, 0, 0))
+            gBattleStruct->switchInAbilityPostponed |= gBitTable[gActiveBattler];
-            return;
+        }
+        else
+        {
+            if (DoSwitchInAbilitiesItems(gActiveBattler))
+                return;
+        }
 
         gSideStatuses[GetBattlerSide(gActiveBattler)] &= ~(SIDE_STATUS_SPIKES_DAMAGED | SIDE_STATUS_TOXIC_SPIKES_DAMAGED | SIDE_STATUS_STEALTH_ROCK_DAMAGED | SIDE_STATUS_STICKY_WEB_DAMAGED);
 
@@ -11016,21 +11050,21 @@ static void Cmd_various(void)
         return;
     }
     case VARIOUS_JUMP_IF_NO_VALID_TARGETS:
-        {
+    {
-            VARIOUS_ARGS(const u8 *jumpInstr);
+        VARIOUS_ARGS(const u8 *jumpInstr);
-            u32 count = 0;
+        u32 count = 0;
 
-            for (i = 0; i < gBattlersCount; i++)
+        for (i = 0; i < gBattlersCount; i++)
-            {
+        {
-                if (GetBattlerSide(i) != GetBattlerSide(gBattlerAttacker) && IsBattlerAlive(i))
+            if (GetBattlerSide(i) != GetBattlerSide(gBattlerAttacker) && IsBattlerAlive(i))
-                    count++;
+                count++;
-            }
-            if (count == 0)
-                gBattlescriptCurrInstr = cmd->jumpInstr;
-            else
-                gBattlescriptCurrInstr = cmd->nextInstr;
-            return;
         }
+        if (count == 0)
+            gBattlescriptCurrInstr = cmd->jumpInstr;
+        else
+            gBattlescriptCurrInstr = cmd->nextInstr;
+        return;
+    }
     case VARIOUS_JUMP_IF_EMERGENCY_EXITED:
     {
         VARIOUS_ARGS(const u8 *jumpInstr);

src/battle_util.c

@@ -3301,7 +3301,7 @@ bool8 HandleWishPerishSongOnTurnEnd(void)
     return FALSE;
 }
 
-#define FAINTED_ACTIONS_MAX_CASE 7
+#define FAINTED_ACTIONS_MAX_CASE 8
 
 bool8 HandleFaintedMonActions(void)
 {
@@ -3386,7 +3386,19 @@ bool8 HandleFaintedMonActions(void)
             else
                 gBattleStruct->faintedActionsState = 4;
             break;
-        case 6:
+        case 6: // All battlers switch-in abilities happen here to prevent them happening against an empty field.
+            for (i = 0; i < gBattlersCount; i++)
+            {
+                if (gBattleStruct->switchInAbilityPostponed & gBitTable[i])
+                {
+                    if (DoSwitchInAbilitiesItems(i))
+                        return TRUE;
+                    gBattleStruct->switchInAbilityPostponed &= ~(gBitTable[i]);
+                }
+            }
+            gBattleStruct->faintedActionsState++;
+            break;
+        case 7:
             if (ItemBattleEffects(ITEMEFFECT_NORMAL, 0, TRUE))
                 return TRUE;
             gBattleStruct->faintedActionsState++;
@@ -4749,6 +4761,7 @@ u8 AbilityBattleEffects(u8 caseID, u8 battler, u16 ability, u8 special, u16 move
         case ABILITY_INTIMIDATE:
             if (!gSpecialStatuses[battler].switchInAbilityDone)
             {
+                gBattlerAttacker = battler;
                 gSpecialStatuses[battler].switchInAbilityDone = TRUE;
                 SET_STATCHANGER(STAT_ATK, 1, TRUE);
                 BattleScriptPushCursorAndCallback(BattleScript_IntimidateActivates);

src/data/trainer_parties.h

@@ -400,17 +400,17 @@ static const struct TrainerMonNoItemDefaultMoves sParty_Rose1[] = {
     {
     .iv = 0,
     .lvl = 14,
-    .species = SPECIES_ROSELIA,
+    .species = SPECIES_PORYGON,
     },
     {
     .iv = 0,
     .lvl = 14,
-    .species = SPECIES_SHROOMISH,
+    .species = SPECIES_PORYGON,
     },
     {
     .iv = 0,
     .lvl = 14,
-    .species = SPECIES_ROSELIA,
+    .species = SPECIES_PORYGON,
     }
 };
 
@@ -9631,17 +9631,17 @@ static const struct TrainerMonNoItemDefaultMoves sParty_Deandre[] = {
     {
     .iv = 0,
     .lvl = 14,
-    .species = SPECIES_ZIGZAGOON,
+    .species = SPECIES_PORYGON,
     },
     {
     .iv = 0,
     .lvl = 14,
-    .species = SPECIES_ARON,
+    .species = SPECIES_PORYGON,
     },
     {
     .iv = 0,
     .lvl = 14,
-    .species = SPECIES_ELECTRIKE,
+    .species = SPECIES_PORYGON,
     }
 };
 

test/ability_intimidate.c

@@ -30,13 +30,12 @@ SINGLE_BATTLE_TEST("Intimidate (opponent) lowers player's attack after switch ou
 SINGLE_BATTLE_TEST("Intimidate (opponent) lowers player's attack after KO", s16 damage)
 {
     u32 ability;
-    KNOWN_FAILING;
     PARAMETRIZE { ability = ABILITY_INTIMIDATE; }
     PARAMETRIZE { ability = ABILITY_RECKLESS; }
     GIVEN {
-        PLAYER(SPECIES_WOBBUFFET) { Speed(2); };
+        PLAYER(SPECIES_WOBBUFFET) { Speed(2); Attack(120) ; };
         OPPONENT(SPECIES_WOBBUFFET) { HP(1); Speed(1); };
-        OPPONENT(SPECIES_STARAPTOR) { Ability(ABILITY_INTIMIDATE); Speed(1); };
+        OPPONENT(SPECIES_STARAPTOR) { Ability(ability); Speed(1); };
     } WHEN {
         TURN { MOVE(player, MOVE_TACKLE); SEND_OUT(opponent, 1); }
         TURN { MOVE(player, MOVE_TACKLE); }
@@ -48,3 +47,48 @@ SINGLE_BATTLE_TEST("Intimidate (opponent) lowers player's attack after KO", s16
         EXPECT_MUL_EQ(results[0].damage, Q_4_12(1.5), results[1].damage);
     }
 }
+
+DOUBLE_BATTLE_TEST("Intimidate doesn't activate on an empty field in a double battle")
+{
+    GIVEN {
+        ASSUME(gBattleMoves[MOVE_EXPLOSION].effect == EFFECT_EXPLOSION);
+        PLAYER(SPECIES_WOBBUFFET) { };
+        PLAYER(SPECIES_WOBBUFFET) { HP(1); };
+        PLAYER(SPECIES_STARAVIA) { Ability(ABILITY_INTIMIDATE); };
+        PLAYER(SPECIES_ABRA);
+        OPPONENT(SPECIES_WOBBUFFET) { HP(1); };
+        OPPONENT(SPECIES_WOBBUFFET) { HP(1); };
+        OPPONENT(SPECIES_STARAPTOR) { Ability(ABILITY_INTIMIDATE); };
+        OPPONENT(SPECIES_WYNAUT);
+    } WHEN {
+        TURN { MOVE(playerLeft, MOVE_EXPLOSION); SEND_OUT(playerLeft, 2); SEND_OUT(opponentLeft, 2); SEND_OUT(playerRight, 3); SEND_OUT(opponentRight, 3); }
+        TURN { MOVE(playerLeft, MOVE_CELEBRATE);}
+    } SCENE {
+        HP_BAR(playerLeft, hp: 0);
+        ANIMATION(ANIM_TYPE_MOVE, MOVE_EXPLOSION, playerLeft);
+        // Leaving these messages as they're not that important to the test, to not exceed MAX_QUEUED_EVENTS.
+        /*
+        MESSAGE("Foe Wobbuffet fainted!");
+        MESSAGE("Wobbuffet fainted!");
+        MESSAGE("Foe Wobbuffet fainted!");
+        MESSAGE("Wobbuffet fainted!");
+        */
+
+        MESSAGE("Go! Staravia!");
+        MESSAGE("2 sent out Staraptor!");
+        MESSAGE("Go! Abra!");
+        MESSAGE("2 sent out Wynaut!");
+
+        ABILITY_POPUP(playerLeft, ABILITY_INTIMIDATE);
+        ANIMATION(ANIM_TYPE_GENERAL, B_ANIM_STATS_CHANGE, opponentLeft);
+        MESSAGE("Staravia's Intimidate cuts Foe Staraptor's ATTACK!");
+        ANIMATION(ANIM_TYPE_GENERAL, B_ANIM_STATS_CHANGE, opponentRight);
+        MESSAGE("Staravia's Intimidate cuts Foe Wynaut's ATTACK!");
+
+        ABILITY_POPUP(opponentLeft, ABILITY_INTIMIDATE);
+        ANIMATION(ANIM_TYPE_GENERAL, B_ANIM_STATS_CHANGE, playerLeft);
+        MESSAGE("Foe Staraptor's Intimidate cuts Staravia's ATTACK!");
+        ANIMATION(ANIM_TYPE_GENERAL, B_ANIM_STATS_CHANGE, playerRight);
+        MESSAGE("Foe Staraptor's Intimidate cuts Abra's ATTACK!");
+    }
+}

test/test_runner.c

@@ -7,7 +7,7 @@
 #include "test.h"
 #include "test_runner.h"
 
-#define TIMEOUT_SECONDS 30
+#define TIMEOUT_SECONDS 49
 
 void CB2_TestRunner(void);