pokerogue/test/battle/double_battle.test.ts

import { Status } from "#app/data/status-effect";
import { AbilityId } from "#enums/ability-id";
import { getGameMode } from "#app/game-mode";
import { GameModes } from "#enums/game-modes";
import { MoveId } from "#enums/move-id";
import { SpeciesId } from "#enums/species-id";
import { StatusEffect } from "#enums/status-effect";
import GameManager from "#test/testUtils/gameManager";
import Phaser from "phaser";
import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";

describe("Double Battles", () => {
  const DOUBLE_CHANCE = 8; // Normal chance of double battle is 1/8

  let phaserGame: Phaser.Game;
  let game: GameManager;

  beforeAll(() => {
    phaserGame = new Phaser.Game({
      type: Phaser.HEADLESS,
    });
  });

  afterEach(() => {
    game.phaseInterceptor.restoreOg();
  });

  beforeEach(() => {
    game = new GameManager(phaserGame);
  });

  // double-battle player's pokemon both fainted in same round, then revive one, and next double battle summons two player's pokemon successfully.
  // (There were bugs that either only summon one when can summon two, player stuck in switchPhase etc)
  it("3v2 edge case: player summons 2 pokemon on the next battle after being fainted and revived", async () => {
    game.override.battleStyle("double").enemyMoveset(MoveId.SPLASH).moveset(MoveId.SPLASH);
    await game.classicMode.startBattle([SpeciesId.BULBASAUR, SpeciesId.CHARIZARD, SpeciesId.SQUIRTLE]);

    game.move.select(MoveId.SPLASH);
    game.move.select(MoveId.SPLASH, 1);

    for (const pokemon of game.scene.getPlayerField()) {
      pokemon.hp = 0;
      pokemon.status = new Status(StatusEffect.FAINT);
      expect(pokemon.isFainted()).toBe(true);
    }

    await game.doKillOpponents();

    await game.phaseInterceptor.to("BattleEndPhase");
    game.doSelectModifier();

    const charizard = game.scene.getPlayerParty().findIndex(p => p.species.speciesId === SpeciesId.CHARIZARD);
    game.doRevivePokemon(charizard);

    await game.phaseInterceptor.to("TurnInitPhase");
    expect(game.scene.getPlayerField().filter(p => !p.isFainted())).toHaveLength(2);
  });

  it("randomly chooses between single and double battles if there is no battle type override", async () => {
    let rngSweepProgress = 0; // Will simulate RNG rolls by slowly increasing from 0 to 1
    let doubleCount = 0;
    let singleCount = 0;

    vi.spyOn(Phaser.Math.RND, "realInRange").mockImplementation((min: number, max: number) => {
      return rngSweepProgress * (max - min) + min;
    });

    game.override
      .enemyMoveset(MoveId.SPLASH)
      .moveset(MoveId.SPLASH)
      .enemyAbility(AbilityId.BALL_FETCH)
      .ability(AbilityId.BALL_FETCH);

    // Play through endless, waves 1 to 9, counting number of double battles from waves 2 to 9
    await game.classicMode.startBattle([SpeciesId.BULBASAUR]);
    game.scene.gameMode = getGameMode(GameModes.ENDLESS);

    for (let i = 0; i < DOUBLE_CHANCE; i++) {
      rngSweepProgress = (i + 0.5) / DOUBLE_CHANCE;

      game.move.select(MoveId.SPLASH);
      await game.doKillOpponents();
      await game.toNextWave();

      if (game.scene.getEnemyParty().length === 1) {
        singleCount++;
      } else if (game.scene.getEnemyParty().length === 2) {
        doubleCount++;
      }
    }

    expect(doubleCount).toBe(1);
    expect(singleCount).toBe(DOUBLE_CHANCE - 1);
  });
});