[Bug] Fix reloads causing RNG inconsistencies

src/phases/encounter-phase.ts

@@ -159,9 +159,11 @@ export class EncounterPhase extends BattlePhase {
               return this.scene.reset(true);
             }
             this.doEncounter();
+            this.scene.resetSeed();
           });
         } else {
           this.doEncounter();
+          this.scene.resetSeed();
         }
       });
     });

src/test/reload.test.ts

@@ -0,0 +1,137 @@
+import { Species } from "#app/enums/species.js";
+import { GameModes, getGameMode } from "#app/game-mode.js";
+import GameManager from "#test/utils/gameManager";
+import { afterEach, beforeAll, beforeEach, describe, expect, it } from "vitest";
+import { SPLASH_ONLY } from "./utils/testUtils";
+import { Moves } from "#app/enums/moves.js";
+import { EnemyCommandPhase } from "#app/phases/enemy-command-phase.js";
+import { DamagePhase } from "#app/phases/damage-phase.js";
+
+describe("Reload", () => {
+  let phaserGame: Phaser.Game;
+  let game: GameManager;
+
+  beforeAll(() => {
+    phaserGame = new Phaser.Game({
+      type: Phaser.HEADLESS,
+    });
+  });
+
+  afterEach(() => {
+    game.phaseInterceptor.restoreOg();
+  });
+
+  beforeEach(() => {
+    game = new GameManager(phaserGame);
+  });
+
+  it("should not have RNG inconsistencies in a Classic run", async () => {
+    await game.classicMode.startBattle();
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+
+  it("should not have RNG inconsistencies after a biome switch", async () => {
+    game.override
+      .startingWave(15)
+      .battleType("single")
+      .startingLevel(100)
+      .enemyLevel(1000)
+      .disableTrainerWaves()
+      .moveset([Moves.KOWTOW_CLEAVE])
+      .enemyMoveset(SPLASH_ONLY);
+    await game.classicMode.startBattle();
+    game.scene.gameMode = getGameMode(GameModes.ENDLESS);
+
+    // Transition from Wave 15 to Wave 16 in order to trigger biome switch
+    game.move.select(Moves.KOWTOW_CLEAVE);
+    await game.phaseInterceptor.runFrom(EnemyCommandPhase).to(DamagePhase);
+    await game.doKillOpponents();
+    await game.toNextWave();
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+
+  it("should not have RNG inconsistencies at a Daily run wild Pokemon fight", async () => {
+    await game.dailyMode.startBattle();
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+
+  it("should not have RNG inconsistencies at a Daily run double battle", async () => {
+    game.override
+      .battleType("double");
+    await game.dailyMode.startBattle();
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+
+  it("should not have RNG inconsistencies at a Daily run Gym Leader fight", async () => {
+    game.override
+      .battleType("single")
+      .startingWave(40);
+    await game.dailyMode.startBattle();
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+
+  it("should not have RNG inconsistencies at a Daily run regular trainer fight", async () => {
+    game.override
+      .battleType("single")
+      .startingWave(45);
+    await game.dailyMode.startBattle();
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+
+  it("should not have RNG inconsistencies at a Daily run wave 50 Boss fight", async () => {
+    game.override
+      .battleType("single")
+      .startingWave(50);
+    await game.runToFinalBossEncounter(game, [Species.BULBASAUR], GameModes.DAILY);
+
+    const preReloadRngState = Phaser.Math.RND.state();
+
+    await game.reload.reloadSession();
+
+    const postReloadRngState = Phaser.Math.RND.state();
+
+    expect(preReloadRngState).toBe(postReloadRngState);
+  }, 20000);
+});

src/test/utils/gameManager.ts

@@ -44,6 +44,7 @@ import { ChallengeModeHelper } from "./helpers/challengeModeHelper";
 import { MoveHelper } from "./helpers/moveHelper";
 import { OverridesHelper } from "./helpers/overridesHelper";
 import { SettingsHelper } from "./helpers/settingsHelper";
+import { ReloadHelper } from "./helpers/reloadHelper";
 
 /**
  * Class to manage the game state and transitions between phases.
@@ -60,6 +61,7 @@ export default class GameManager {
   public readonly dailyMode: DailyModeHelper;
   public readonly challengeMode: ChallengeModeHelper;
   public readonly settings: SettingsHelper;
+  public readonly reload: ReloadHelper;
 
   /**
    * Creates an instance of GameManager.
@@ -81,6 +83,7 @@ export default class GameManager {
     this.dailyMode = new DailyModeHelper(this);
     this.challengeMode = new ChallengeModeHelper(this);
     this.settings = new SettingsHelper(this);
+    this.reload = new ReloadHelper(this);
   }
 
   /**

src/test/utils/helpers/reloadHelper.ts

@@ -0,0 +1,89 @@
+import { BattleType } from "#app/battle";
+import PokemonData from "#app/system/pokemon-data";
+import ArenaData from "#app/system/arena-data";
+import PersistentModifierData from "#app/system/modifier-data";
+import ChallengeData from "#app/system/challenge-data";
+import TrainerData from "#app/system/trainer-data";
+import { SessionSaveData } from "#app/system/game-data";
+import { GameManagerHelper } from "./gameManagerHelper";
+import { TitlePhase } from "#app/phases/title-phase";
+import { Mode } from "#app/ui/ui";
+import { vi } from "vitest";
+import { BattleStyle } from "#app/enums/battle-style";
+import { CommandPhase } from "#app/phases/command-phase";
+import { TurnInitPhase } from "#app/phases/turn-init-phase";
+
+/**
+ * Helper to allow reloading sessions in unit tests.
+ */
+export class ReloadHelper extends GameManagerHelper {
+  /**
+   * Return a save data object to be used for reloading the current session.
+   * @returns A save data object for the current session.
+   */
+  getSessionSaveData() : SessionSaveData {
+    // Copied from game-data.ts
+    const scene = this.game.scene;
+    const ret = {
+      seed: scene.seed,
+      playTime: scene.sessionPlayTime,
+      gameMode: scene.gameMode.modeId,
+      party: scene.getParty().map(p => new PokemonData(p)),
+      enemyParty: scene.getEnemyParty().map(p => new PokemonData(p)),
+      modifiers: scene.findModifiers(() => true).map(m => new PersistentModifierData(m, true)),
+      enemyModifiers: scene.findModifiers(() => true, false).map(m => new PersistentModifierData(m, false)),
+      arena: new ArenaData(scene.arena),
+      pokeballCounts: scene.pokeballCounts,
+      money: scene.money,
+      score: scene.score,
+      waveIndex: scene.currentBattle.waveIndex,
+      battleType: scene.currentBattle.battleType,
+      trainer: scene.currentBattle.battleType === BattleType.TRAINER ? new TrainerData(scene.currentBattle.trainer) : null,
+      gameVersion: scene.game.config.gameVersion,
+      timestamp: new Date().getTime(),
+      challenges: scene.gameMode.challenges.map(c => new ChallengeData(c))
+    } as SessionSaveData;
+    return ret;
+  }
+
+  /**
+   * Simulate reloading the session from the title screen, until reaching the
+   * beginning of the first turn (equivalent to running `startBattle()`) for
+   * the reloaded session.
+   */
+  async reloadSession() : Promise<void> {
+    const scene = this.game.scene;
+    const sessionData = this.getSessionSaveData();
+    const titlePhase = new TitlePhase(scene);
+
+    scene.clearPhaseQueue();
+
+    // Set the last saved session to the desired session data
+    vi.spyOn(scene.gameData, "getSession").mockReturnValue(
+      new Promise((resolve, reject) => {
+        resolve(sessionData);
+      })
+    );
+    scene.unshiftPhase(titlePhase);
+    this.game.endPhase(); // End the currently ongoing battle
+
+    titlePhase.loadSaveSlot(-1); // Load the desired session data
+    this.game.phaseInterceptor.shift(); // Loading the save slot also ended TitlePhase, clean it up
+
+    // Run through prompts for switching Pokemon, copied from classicModeHelper.ts
+    if (this.game.scene.battleStyle === BattleStyle.SWITCH) {
+      this.game.onNextPrompt("CheckSwitchPhase", Mode.CONFIRM, () => {
+        this.game.setMode(Mode.MESSAGE);
+        this.game.endPhase();
+      }, () => this.game.isCurrentPhase(CommandPhase) || this.game.isCurrentPhase(TurnInitPhase));
+
+      this.game.onNextPrompt("CheckSwitchPhase", Mode.CONFIRM, () => {
+        this.game.setMode(Mode.MESSAGE);
+        this.game.endPhase();
+      }, () => this.game.isCurrentPhase(CommandPhase) || this.game.isCurrentPhase(TurnInitPhase));
+    }
+
+    await this.game.phaseInterceptor.to(CommandPhase);
+    console.log("==================[New Turn]==================");
+  }
+}

src/test/utils/phaseInterceptor.ts

@@ -16,6 +16,7 @@ import { MoveEffectPhase } from "#app/phases/move-effect-phase";
 import { MoveEndPhase } from "#app/phases/move-end-phase";
 import { MovePhase } from "#app/phases/move-phase";
 import { NewBattlePhase } from "#app/phases/new-battle-phase";
+import { NewBiomeEncounterPhase } from "#app/phases/new-biome-encounter-phase.js";
 import { NextEncounterPhase } from "#app/phases/next-encounter-phase";
 import { PartyHealPhase } from "#app/phases/party-heal-phase";
 import { PostSummonPhase } from "#app/phases/post-summon-phase";
@@ -62,6 +63,7 @@ export default class PhaseInterceptor {
     [TitlePhase, this.startPhase],
     [SelectGenderPhase, this.startPhase],
     [EncounterPhase, this.startPhase],
+    [NewBiomeEncounterPhase, this.startPhase],
     [SelectStarterPhase, this.startPhase],
     [PostSummonPhase, this.startPhase],
     [SummonPhase, this.startPhase],
@@ -237,6 +239,22 @@ export default class PhaseInterceptor {
     this.scene.shiftPhase();
   }
 
+  /**
+   * Remove the current phase from the phase interceptor.
+   *
+   * Do not call this unless absolutely necessary. This function is intended
+   * for cleaning up the phase interceptor when, for whatever reason, a phase
+   * is manually ended without using the phase interceptor.
+   *
+   * @param shouldRun Whether or not the current scene should also be run.
+   */
+  shift(shouldRun: boolean = false) : void {
+    this.onHold.shift();
+    if (shouldRun) {
+      this.scene.shiftPhase();
+    }
+  }
+
   /**
    * Method to initialize phases and their corresponding methods.
    */