Update harsh sun, heavy rain, and heavy winds to turn off if their respective abilities are no longer on the field

src/data/ability.ts

@@ -1620,6 +1620,16 @@ export class PreSwitchOutHealAbAttr extends PreSwitchOutAbAttr {
   }
 }
 
+export class PreSwitchOutWeatherChangeAbAttr extends PreSwitchOutAbAttr {
+  applyPreSwitchOut(pokemon: Pokemon, passive: boolean, args: any[]): boolean | Promise<boolean> {
+    if (pokemon.scene.arena.weather?.isImmutable()) {
+      return pokemon.scene.arena.weather?.isAbilityOnField(pokemon.scene) ? false : pokemon.scene.arena.trySetWeather(WeatherType.NONE, true);
+    }
+
+    return false;
+    }
+}
+
 export class PreStatChangeAbAttr extends AbAttr {
   applyPreStatChange(pokemon: Pokemon, passive: boolean, stat: BattleStat, cancelled: Utils.BooleanHolder, args: any[]): boolean | Promise<boolean> {
     return false;
@@ -3320,12 +3330,15 @@ export function initAbilities() {
       .unimplemented(),
     new Ability(Abilities.PRIMORDIAL_SEA, 6)
       .attr(PostSummonWeatherChangeAbAttr, WeatherType.HEAVY_RAIN)
+      .attr(PreSwitchOutWeatherChangeAbAttr)
       .attr(PostBiomeChangeWeatherChangeAbAttr, WeatherType.HEAVY_RAIN),
     new Ability(Abilities.DESOLATE_LAND, 6)
       .attr(PostSummonWeatherChangeAbAttr, WeatherType.HARSH_SUN)
+      .attr(PreSwitchOutWeatherChangeAbAttr)
       .attr(PostBiomeChangeWeatherChangeAbAttr, WeatherType.HARSH_SUN),
     new Ability(Abilities.DELTA_STREAM, 6)
       .attr(PostSummonWeatherChangeAbAttr, WeatherType.STRONG_WINDS)
+      .attr(PreSwitchOutWeatherChangeAbAttr)
       .attr(PostBiomeChangeWeatherChangeAbAttr, WeatherType.STRONG_WINDS),
     new Ability(Abilities.STAMINA, 7)
       .attr(PostDefendStatChangeAbAttr, (target, user, move) => move.category !== MoveCategory.STATUS, BattleStat.DEF, 1),

src/data/weather.ts

@@ -7,6 +7,7 @@ import * as Utils from "../utils";
 import BattleScene from "../battle-scene";
 import { SuppressWeatherEffectAbAttr } from "./ability";
 import { TerrainType } from "./terrain";
+import { Abilities } from "./enums/abilities";
 
 export enum WeatherType {
   NONE,
@@ -116,6 +117,39 @@ export class Weather {
 
     return false;
   }
+
+  isAbilityOnField(scene: BattleScene): boolean {
+    const field = scene.getField(true);
+    let abilitiesOnField = 0;
+
+    for (let pokemon of field) {
+      let ability = pokemon.getAbility();
+      switch (this.weatherType) {
+        case WeatherType.HARSH_SUN:
+          if (ability.id === Abilities.DESOLATE_LAND)
+            abilitiesOnField++
+          if (pokemon.hasPassive() && pokemon.getPassiveAbility().id === Abilities.DESOLATE_LAND)
+            abilitiesOnField++
+          break;
+        case WeatherType.HEAVY_RAIN:
+          if (ability.id === Abilities.PRIMORDIAL_SEA)
+            abilitiesOnField++
+          if (pokemon.hasPassive() && pokemon.getPassiveAbility().id === Abilities.PRIMORDIAL_SEA)
+            abilitiesOnField++
+          break;
+        case WeatherType.STRONG_WINDS:
+          if (ability.id === Abilities.DELTA_STREAM)
+            abilitiesOnField++
+          if (pokemon.hasPassive() && pokemon.getPassiveAbility().id === Abilities.DELTA_STREAM)
+            abilitiesOnField++
+          break;
+        default:
+          break;
+      }
+    }
+
+    return abilitiesOnField > 1;
+  }
 }
 
 export function getWeatherStartMessage(weatherType: WeatherType): string {