remove assist array from battle struct

include/battle.h

@@ -534,7 +534,6 @@ struct BattleStruct
     u8 wildVictorySong;
     u8 dynamicMoveType;
     u8 wrappedBy[MAX_BATTLERS_COUNT];
-    u16 assistPossibleMoves[PARTY_SIZE * MAX_MON_MOVES]; // Each of mons can know max 4 moves.
     u8 focusPunchBattlerId;
     u8 battlerPreventingSwitchout;
     u8 moneyMultiplier:6;

src/battle_script_commands.c

@@ -23,6 +23,7 @@
 #include "main.h"
 #include "palette.h"
 #include "money.h"
+#include "malloc.h"
 #include "bg.h"
 #include "string_util.h"
 #include "pokemon_icon.h"
@@ -14766,45 +14767,49 @@ static void Cmd_assistattackselect(void)
     s32 chooseableMovesNo = 0;
     struct Pokemon *party;
     s32 monId, moveId;
-    u16 *validMoves = gBattleStruct->assistPossibleMoves;
+    u16 *validMoves = Alloc(sizeof(u16) * PARTY_SIZE * MAX_MON_MOVES);
 
-    if (GET_BATTLER_SIDE(gBattlerAttacker) != B_SIDE_PLAYER)
-        party = gEnemyParty;
-    else
-        party = gPlayerParty;
-
-    for (monId = 0; monId < PARTY_SIZE; monId++)
+    if (validMoves != NULL)
     {
-        if (monId == gBattlerPartyIndexes[gBattlerAttacker])
-            continue;
-        if (GetMonData(&party[monId], MON_DATA_SPECIES_OR_EGG) == SPECIES_NONE)
-            continue;
-        if (GetMonData(&party[monId], MON_DATA_SPECIES_OR_EGG) == SPECIES_EGG)
-            continue;
+        if (GET_BATTLER_SIDE(gBattlerAttacker) != B_SIDE_PLAYER)
+            party = gEnemyParty;
+        else
+            party = gPlayerParty;
 
-        for (moveId = 0; moveId < MAX_MON_MOVES; moveId++)
+        for (monId = 0; monId < PARTY_SIZE; monId++)
         {
-            s32 i = 0;
-            u16 move = GetMonData(&party[monId], MON_DATA_MOVE1 + moveId);
-
-            if (sForbiddenMoves[move] & FORBIDDEN_ASSIST)
+            if (monId == gBattlerPartyIndexes[gBattlerAttacker])
+                continue;
+            if (GetMonData(&party[monId], MON_DATA_SPECIES_OR_EGG) == SPECIES_NONE)
+                continue;
+            if (GetMonData(&party[monId], MON_DATA_SPECIES_OR_EGG) == SPECIES_EGG)
                 continue;
 
-            validMoves[chooseableMovesNo] = move;
-            chooseableMovesNo++;
+            for (moveId = 0; moveId < MAX_MON_MOVES; moveId++)
+            {
+                u16 move = GetMonData(&party[monId], MON_DATA_MOVE1 + moveId);
+
+                if (sForbiddenMoves[move] & FORBIDDEN_ASSIST)
+                    continue;
+
+                validMoves[chooseableMovesNo++] = move;
+            }
         }
     }
+
     if (chooseableMovesNo)
     {
         gHitMarker &= ~HITMARKER_ATTACKSTRING_PRINTED;
-        gCalledMove = validMoves[((Random() & 0xFF) * chooseableMovesNo) >> 8];
+        gCalledMove = validMoves[Random() % chooseableMovesNo];
         gBattlerTarget = GetMoveTarget(gCalledMove, NO_TARGET_OVERRIDE);
         gBattlescriptCurrInstr = cmd->nextInstr;
     }
     else
     {
         gBattlescriptCurrInstr = cmd->failInstr;
     }
+
+    TRY_FREE_AND_SET_NULL(validMoves);
 }
 
 static void Cmd_trysetmagiccoat(void)

test/move_effect_assist.c

@@ -0,0 +1,22 @@
+#include "global.h"
+#include "test_battle.h"
+
+ASSUMPTIONS
+{
+    ASSUME(gBattleMoves[MOVE_ASSIST].effect == EFFECT_ASSIST);
+}
+
+SINGLE_BATTLE_TEST("Assist fails if there are no valid moves to choose from")
+{
+    GIVEN {
+        PLAYER(SPECIES_WOBBUFFET) {Moves(MOVE_ASSIST, MOVE_CELEBRATE, MOVE_METRONOME, MOVE_ME_FIRST); }
+        PLAYER(SPECIES_WOBBUFFET) {Moves(MOVE_ASSIST, MOVE_ENDURE, MOVE_DRAGON_TAIL, MOVE_SPOTLIGHT); }
+        OPPONENT(SPECIES_WOBBUFFET);
+    } WHEN {
+        TURN { MOVE(player, MOVE_ASSIST); }
+    } SCENE {
+        MESSAGE("Wobbuffet used Assist!");
+        NOT ANIMATION(ANIM_TYPE_MOVE, MOVE_ASSIST, player);
+        MESSAGE("But it failed!");
+    }
+}

test/test_runner_battle.c

@@ -1227,6 +1227,7 @@ void Move(u32 sourceLine, struct BattlePokemon *battler, struct MoveContext ctx)
         const struct BattleMove *move = &gBattleMoves[moveId];
         if (move->target == MOVE_TARGET_RANDOM
          || move->target == MOVE_TARGET_BOTH
+         || move->target == MOVE_TARGET_DEPENDS
          || move->target == MOVE_TARGET_FOES_AND_ALLY
          || move->target == MOVE_TARGET_OPPONENTS_FIELD
          || move->target == MOVE_TARGET_ALL_BATTLERS)