Even more array improvements

src/@types/trainer-funcs.ts

@@ -7,8 +7,8 @@ import type { TrainerPartyTemplate } from "#trainers/trainer-party-template";
 
 export type PartyTemplateFunc = () => TrainerPartyTemplate;
 export type PartyMemberFunc = (level: number, strength: PartyMemberStrength) => EnemyPokemon;
-export type GenModifiersFunc = (party: EnemyPokemon[]) => PersistentModifier[];
+export type GenModifiersFunc = (party: readonly EnemyPokemon[]) => PersistentModifier[];
-export type GenAIFunc = (party: EnemyPokemon[]) => void;
+export type GenAIFunc = (party: readonly EnemyPokemon[]) => void;
 
 export interface TrainerTierPools {
   [key: number]: SpeciesId[];

src/battle.ts

@@ -526,24 +526,25 @@ export class FixedBattleConfig {
 
 /**
  * Helper function to generate a random trainer for evil team trainers and the elite 4/champion
- * @param trainerPool The TrainerType or list of TrainerTypes that can possibly be generated
+ * @param trainerPool - An array of trainer types to choose from. If an entry is an array, a random trainer type will be chosen from that array
- * @param randomGender whether or not to randomly (50%) generate a female trainer (for use with evil team grunts)
+ * @param randomGender - Whether or not to randomly (50%) generate a female trainer (for use with evil team grunts)
- * @param seedOffset the seed offset to use for the random generation of the trainer
+ * @param seedOffset - The seed offset to use for the random generation of the trainer
- * @returns the generated trainer
+ * @returns A function to get a random trainer
  */
 export function getRandomTrainerFunc(
-  trainerPool: (TrainerType | TrainerType[])[],
+  trainerPool: readonly (TrainerType | readonly TrainerType[])[],
   randomGender = false,
   seedOffset = 0,
 ): GetTrainerFunc {
   return () => {
     const rand = randSeedInt(trainerPool.length);
-    const trainerTypes: TrainerType[] = [];
+    const trainerTypes: TrainerType[] = new Array(trainerPool.length);
 
     globalScene.executeWithSeedOffset(() => {
-      for (const trainerPoolEntry of trainerPool) {
+      for (let i = 0; i < trainerPool.length; i++) {
+        const trainerPoolEntry = trainerPool[i];
         const trainerType = Array.isArray(trainerPoolEntry) ? randSeedItem(trainerPoolEntry) : trainerPoolEntry;
-        trainerTypes.push(trainerType);
+        trainerTypes[i] = trainerType;
       }
     }, seedOffset);
 

src/constants.ts

@@ -23,7 +23,7 @@ export const TYPE_BOOST_ITEM_BOOST_PERCENT = 20;
 /**
  * The default species that a new player can choose from
  */
-export const defaultStarterSpecies: SpeciesId[] = [
+export const defaultStarterSpecies: readonly SpeciesId[] = [
   SpeciesId.BULBASAUR,
   SpeciesId.CHARMANDER,
   SpeciesId.SQUIRTLE,

src/data/balance/biomes.ts

@@ -5,6 +5,7 @@ import { PokemonType } from "#enums/pokemon-type";
 import { SpeciesId } from "#enums/species-id";
 import { TimeOfDay } from "#enums/time-of-day";
 import { TrainerType } from "#enums/trainer-type";
+import type { Mutable } from "#types/type-helpers";
 import { randSeedInt } from "#utils/common";
 import { getEnumValues } from "#utils/enums";
 import { toCamelCase } from "#utils/strings";
@@ -88,19 +89,19 @@ export enum BiomePoolTier {
 export const uncatchableSpecies: SpeciesId[] = [];
 
 interface SpeciesTree {
-  [key: number]: SpeciesId[]
+  readonly [key: number]: SpeciesId[]
 }
 
 export interface PokemonPools {
-  [key: number]: (SpeciesId | SpeciesTree)[]
+  readonly [key: number]: (SpeciesId | SpeciesTree)[]
 }
 
 interface BiomeTierPokemonPools {
-  [key: number]: PokemonPools
+  readonly [key: number]: PokemonPools
 }
 
 interface BiomePokemonPools {
-  [key: number]: BiomeTierPokemonPools
+  readonly [key: number]: BiomeTierPokemonPools
 }
 
 export interface BiomeTierTod {
@@ -110,17 +111,17 @@ export interface BiomeTierTod {
 }
 
 export interface CatchableSpecies{
-  [key: number]: BiomeTierTod[]
+  readonly [key: number]: readonly BiomeTierTod[]
 }
 
 export const catchableSpecies: CatchableSpecies = {};
 
 export interface BiomeTierTrainerPools {
-  [key: number]: TrainerType[]
+  readonly [key: number]: readonly TrainerType[]
 }
 
 export interface BiomeTrainerPools {
-  [key: number]: BiomeTierTrainerPools
+  readonly [key: number]: BiomeTierTrainerPools
 }
 
 export const biomePokemonPools: BiomePokemonPools = {
@@ -7621,12 +7622,10 @@ export function initBiomes() {
       ? biomeLinks[biome] as (BiomeId | [ BiomeId, number ])[]
       : [ biomeLinks[biome] as BiomeId ];
     for (const linkedBiomeEntry of linkedBiomes) {
-      const linkedBiome = !Array.isArray(linkedBiomeEntry)
+      const linkedBiome = Array.isArray(linkedBiomeEntry)
-        ? linkedBiomeEntry as BiomeId
+        ? linkedBiomeEntry[0] : linkedBiomeEntry as BiomeId;
-        : linkedBiomeEntry[0];
+      const biomeChance = Array.isArray(linkedBiomeEntry)
-      const biomeChance = !Array.isArray(linkedBiomeEntry)
+        ? linkedBiomeEntry[1] : 1;
-        ? 1
-        : linkedBiomeEntry[1];
       if (!biomeDepths.hasOwnProperty(linkedBiome) || biomeChance < biomeDepths[linkedBiome][1] || (depth < biomeDepths[linkedBiome][0] && biomeChance === biomeDepths[linkedBiome][1])) {
         biomeDepths[linkedBiome] = [ depth + 1, biomeChance ];
         traverseBiome(linkedBiome, depth + 1);
@@ -7638,15 +7637,15 @@ export function initBiomes() {
   biomeDepths[BiomeId.END] = [ Object.values(biomeDepths).map(d => d[0]).reduce((max: number, value: number) => Math.max(max, value), 0) + 1, 1 ];
 
   for (const biome of getEnumValues(BiomeId)) {
-    biomePokemonPools[biome] = {};
+    (biomePokemonPools[biome] as Mutable<typeof biomePokemonPools[number]>) = {};
-    biomeTrainerPools[biome] = {};
+    (biomeTrainerPools[biome] as Mutable<typeof biomeTrainerPools[number]>) = {};
 
     for (const tier of getEnumValues(BiomePoolTier)) {
-      biomePokemonPools[biome][tier] = {};
+      (biomePokemonPools[biome][tier] as Mutable<typeof biomePokemonPools[number][number]>) = {};
-      biomeTrainerPools[biome][tier] = [];
+      (biomeTrainerPools[biome][tier] as Mutable<typeof biomeTrainerPools[number][number]>) = [];
 
       for (const tod of getEnumValues(TimeOfDay)) {
-        biomePokemonPools[biome][tier][tod] = [];
+        (biomePokemonPools[biome][tier][tod] as Mutable<typeof biomePokemonPools[number][number][number]>) = [];
       }
     }
   }
@@ -7663,8 +7662,9 @@ export function initBiomes() {
       uncatchableSpecies.push(speciesId);
     }
 
+    type mutableSpecies = Mutable<typeof catchableSpecies[SpeciesId]>;
     // array of biome options for the current species
-    catchableSpecies[speciesId] = [];
+    (catchableSpecies[speciesId] as mutableSpecies) = [];
 
     for (const b of biomeEntries) {
       const biome = b[0];
@@ -7675,7 +7675,7 @@ export function initBiomes() {
           : [ b[2] ]
         : [ TimeOfDay.ALL ];
 
-      catchableSpecies[speciesId].push({
+      (catchableSpecies[speciesId] as mutableSpecies).push({
         biome: biome as BiomeId,
         tier: tier as BiomePoolTier,
         tod: timesOfDay as TimeOfDay[]
@@ -7735,12 +7735,13 @@ export function initBiomes() {
             };
             for (let s = 1; s < entry.length; s++) {
               const speciesId = entry[s];
+              // biome-ignore lint/nursery/noShadow: one-off
               const prevolution = entry.flatMap((s: string | number) => pokemonEvolutions[s]).find(e => e && e.speciesId === speciesId);
               const level = prevolution.level - (prevolution.level === 1 ? 1 : 0) + (prevolution.wildDelay * 10) - (tier >= BiomePoolTier.BOSS ? 10 : 0);
-              if (!newEntry.hasOwnProperty(level)) {
+              if (newEntry.hasOwnProperty(level)) {
-                newEntry[level] = [ speciesId ];
-              } else {
                 newEntry[level].push(speciesId);
+              } else {
+                newEntry[level] = [ speciesId ];
               }
             }
             biomeTierTimePool[e] = newEntry;
@@ -7763,7 +7764,7 @@ export function initBiomes() {
       }
 
       const biomeTierPool = biomeTrainerPools[biome][tier];
-      biomeTierPool.push(trainerType);
+      (biomeTierPool as Mutable<typeof biomeTierPool>).push(trainerType);
     }
     //outputPools();
   }

src/data/battler-tags.ts

@@ -2154,8 +2154,8 @@ export class HighestStatBoostTag extends AbilityBattlerTag {
 }
 
 export class WeatherHighestStatBoostTag extends HighestStatBoostTag {
-  #weatherTypes: WeatherType[];
+  readonly #weatherTypes: readonly WeatherType[];
-  public get weatherTypes(): WeatherType[] {
+  public get weatherTypes(): readonly WeatherType[] {
     return this.#weatherTypes;
   }
 
@@ -2166,8 +2166,8 @@ export class WeatherHighestStatBoostTag extends HighestStatBoostTag {
 }
 
 export class TerrainHighestStatBoostTag extends HighestStatBoostTag {
-  #terrainTypes: TerrainType[];
+  readonly #terrainTypes: readonly TerrainType[];
-  public get terrainTypes(): TerrainType[] {
+  public get terrainTypes(): readonly TerrainType[] {
     return this.#terrainTypes;
   }
 

src/data/egg.ts

@@ -485,14 +485,14 @@ export class Egg {
      * and being the same each time
      */
     let totalWeight = 0;
-    const speciesWeights: number[] = [];
+    const speciesWeights = new Array<number>(speciesPool.length);
-    for (const speciesId of speciesPool) {
+    for (const [idx, speciesId] of speciesPool.entries()) {
       // Accounts for species that have starter costs outside of the normal range for their EggTier
       const speciesCostClamped = Phaser.Math.Clamp(speciesStarterCosts[speciesId], minStarterValue, maxStarterValue);
       const weight = Math.floor(
         (((maxStarterValue - speciesCostClamped) / (maxStarterValue - minStarterValue + 1)) * 1.5 + 1) * 100,
       );
-      speciesWeights.push(totalWeight + weight);
+      speciesWeights[idx] = totalWeight + weight;
       totalWeight += weight;
     }
 

src/data/pokemon-forms.ts

@@ -25,6 +25,7 @@ import { SpeciesId } from "#enums/species-id";
 import { WeatherType } from "#enums/weather-type";
 import type { Pokemon } from "#field/pokemon";
 import type { Constructor, nil } from "#types/common";
+import type { Mutable } from "#types/type-helpers";
 
 export type SpeciesFormChangeConditionPredicate = (p: Pokemon) => boolean;
 export type SpeciesFormChangeConditionEnforceFunc = (p: Pokemon) => void;
@@ -116,7 +117,7 @@ function getSpeciesDependentFormChangeCondition(species: SpeciesId): SpeciesForm
 }
 
 interface PokemonFormChanges {
-  [key: string]: SpeciesFormChange[];
+  [key: string]: readonly SpeciesFormChange[];
 }
 
 // biome-ignore format: manually formatted
@@ -608,6 +609,6 @@ export function initPokemonForms() {
         );
       }
     }
-    formChanges.push(...newFormChanges);
+    (formChanges as Mutable<typeof formChanges>).push(...newFormChanges);
   }
 }

src/data/pokemon-forms/form-change-triggers.ts

@@ -240,9 +240,9 @@ export class SpeciesFormChangeWeatherTrigger extends SpeciesFormChangeTrigger {
   /** The ability that  triggers the form change */
   public ability: AbilityId;
   /** The list of weathers that trigger the form change */
-  public weathers: WeatherType[];
+  public readonly weathers: readonly WeatherType[];
 
-  constructor(ability: AbilityId, weathers: WeatherType[]) {
+  constructor(ability: AbilityId, weathers: readonly WeatherType[]) {
     super();
     this.ability = ability;
     this.weathers = weathers;
@@ -278,9 +278,9 @@ export class SpeciesFormChangeRevertWeatherFormTrigger extends SpeciesFormChange
   /** The ability that triggers the form change*/
   public ability: AbilityId;
   /** The list of weathers that will also trigger a form change to original form */
-  public weathers: WeatherType[];
+  public readonly weathers: readonly WeatherType[];
 
-  constructor(ability: AbilityId, weathers: WeatherType[]) {
+  constructor(ability: AbilityId, weathers: readonly WeatherType[]) {
     super();
     this.ability = ability;
     this.weathers = weathers;
@@ -310,9 +310,10 @@ export class SpeciesFormChangeRevertWeatherFormTrigger extends SpeciesFormChange
 }
 
 export function getSpeciesFormChangeMessage(pokemon: Pokemon, formChange: SpeciesFormChange, preName: string): string {
-  const isMega = formChange.formKey.indexOf(SpeciesFormKey.MEGA) > -1;
+  const formKey = formChange.formKey;
-  const isGmax = formChange.formKey.indexOf(SpeciesFormKey.GIGANTAMAX) > -1;
+  const isMega = formKey.indexOf(SpeciesFormKey.MEGA) > -1;
-  const isEmax = formChange.formKey.indexOf(SpeciesFormKey.ETERNAMAX) > -1;
+  const isGmax = formKey.indexOf(SpeciesFormKey.GIGANTAMAX) > -1;
+  const isEmax = formKey.indexOf(SpeciesFormKey.ETERNAMAX) > -1;
   const isRevert = !isMega && formChange.formKey === pokemon.species.forms[0].formKey;
   if (isMega) {
     return i18next.t("battlePokemonForm:megaChange", {

src/field/pokemon.ts

@@ -2140,7 +2140,8 @@ export abstract class Pokemon extends Phaser.GameObjects.Container {
    * Suppresses an ability and calls its onlose attributes
    */
   public suppressAbility() {
-    [true, false].forEach(passive => applyOnLoseAbAttrs({ pokemon: this, passive }));
+    applyOnLoseAbAttrs({ pokemon: this, passive: true });
+    applyOnLoseAbAttrs({ pokemon: this, passive: false });
     this.summonData.abilitySuppressed = true;
   }
 

src/field/trainer.ts

@@ -642,14 +642,14 @@ export class Trainer extends Phaser.GameObjects.Container {
     }
   }
 
-  genModifiers(party: EnemyPokemon[]): PersistentModifier[] {
+  genModifiers(party: readonly EnemyPokemon[]): PersistentModifier[] {
     if (this.config.genModifiersFunc) {
       return this.config.genModifiersFunc(party);
     }
     return [];
   }
 
-  genAI(party: EnemyPokemon[]) {
+  genAI(party: readonly EnemyPokemon[]) {
     if (this.config.genAIFuncs) {
       this.config.genAIFuncs.forEach(f => f(party));
     }

src/modifier/modifier-type.ts

@@ -277,7 +277,7 @@ export class ModifierType {
   }
 }
 
-type ModifierTypeGeneratorFunc = (party: Pokemon[], pregenArgs?: any[]) => ModifierType | null;
+type ModifierTypeGeneratorFunc = (party: readonly Pokemon[], pregenArgs?: any[]) => ModifierType | null;
 
 export class ModifierTypeGenerator extends ModifierType {
   private genTypeFunc: ModifierTypeGeneratorFunc;
@@ -287,7 +287,7 @@ export class ModifierTypeGenerator extends ModifierType {
     this.genTypeFunc = genTypeFunc;
   }
 
-  generateType(party: Pokemon[], pregenArgs?: any[]) {
+  generateType(party: readonly Pokemon[], pregenArgs?: any[]) {
     const ret = this.genTypeFunc(party, pregenArgs);
     if (ret) {
       ret.id = this.id;
@@ -2360,7 +2360,11 @@ const tierWeights = [768 / 1024, 195 / 1024, 48 / 1024, 12 / 1024, 1 / 1024];
  */
 export const itemPoolChecks: Map<ModifierTypeKeys, boolean | undefined> = new Map();
 
-export function regenerateModifierPoolThresholds(party: Pokemon[], poolType: ModifierPoolType, rerollCount = 0) {
+export function regenerateModifierPoolThresholds(
+  party: readonly Pokemon[],
+  poolType: ModifierPoolType,
+  rerollCount = 0,
+) {
   const pool = getModifierPoolForType(poolType);
   itemPoolChecks.forEach((_v, k) => {
     itemPoolChecks.set(k, false);
@@ -2906,7 +2910,7 @@ export class ModifierTypeOption {
  * @param party The player's party.
  * @returns A number between 0 and 14 based on the party's total luck value, or a random number between 0 and 14 if the player is in Daily Run mode.
  */
-export function getPartyLuckValue(party: Pokemon[]): number {
+export function getPartyLuckValue(party: readonly Pokemon[]): number {
   if (globalScene.gameMode.isDaily) {
     const DailyLuck = new NumberHolder(0);
     globalScene.executeWithSeedOffset(

src/phases/battle-phase.ts

@@ -12,7 +12,7 @@ export abstract class BattlePhase extends Phase {
     const tintSprites = globalScene.currentBattle.trainer.getTintSprites();
     for (let i = 0; i < sprites.length; i++) {
       const visible = !trainerSlot || !i === (trainerSlot === TrainerSlot.TRAINER) || sprites.length < 2;
-      [sprites[i], tintSprites[i]].map(sprite => {
+      [sprites[i], tintSprites[i]].forEach(sprite => {
         if (visible) {
           sprite.x = trainerSlot || sprites.length < 2 ? 0 : i ? 16 : -16;
         }

src/timed-event-manager.ts

@@ -18,59 +18,59 @@ export enum EventType {
 }
 
 interface EventBanner {
-  bannerKey?: string;
+  readonly bannerKey?: string;
-  xOffset?: number;
+  readonly xOffset?: number;
-  yOffset?: number;
+  readonly yOffset?: number;
-  scale?: number;
+  readonly scale?: number;
-  availableLangs?: string[];
+  readonly availableLangs?: readonly string[];
 }
 
 interface EventEncounter {
-  species: SpeciesId;
+  readonly species: SpeciesId;
-  blockEvolution?: boolean;
+  readonly blockEvolution?: boolean;
-  formIndex?: number;
+  readonly formIndex?: number;
 }
 
 interface EventMysteryEncounterTier {
-  mysteryEncounter: MysteryEncounterType;
+  readonly mysteryEncounter: MysteryEncounterType;
-  tier?: MysteryEncounterTier;
+  readonly tier?: MysteryEncounterTier;
-  disable?: boolean;
+  readonly disable?: boolean;
 }
 
 interface EventWaveReward {
-  wave: number;
+  readonly wave: number;
-  type: string;
+  readonly type: string;
 }
 
-type EventMusicReplacement = [string, string];
+type EventMusicReplacement = readonly [string, string];
 
 interface EventChallenge {
-  challenge: Challenges;
+  readonly challenge: Challenges;
-  value: number;
+  readonly value: number;
 }
 
 interface TimedEvent extends EventBanner {
-  name: string;
+  readonly name: string;
-  eventType: EventType;
+  readonly eventType: EventType;
-  shinyMultiplier?: number;
+  readonly shinyMultiplier?: number;
-  classicFriendshipMultiplier?: number;
+  readonly classicFriendshipMultiplier?: number;
-  luckBoost?: number;
+  readonly luckBoost?: number;
-  upgradeUnlockedVouchers?: boolean;
+  readonly upgradeUnlockedVouchers?: boolean;
-  startDate: Date;
+  readonly startDate: Date;
-  endDate: Date;
+  readonly endDate: Date;
-  eventEncounters?: EventEncounter[];
+  readonly eventEncounters?: readonly EventEncounter[];
-  delibirdyBuff?: string[];
+  readonly delibirdyBuff?: readonly string[];
-  weather?: WeatherPoolEntry[];
+  readonly weather?: readonly WeatherPoolEntry[];
-  mysteryEncounterTierChanges?: EventMysteryEncounterTier[];
+  readonly mysteryEncounterTierChanges?: readonly EventMysteryEncounterTier[];
-  luckBoostedSpecies?: SpeciesId[];
+  readonly luckBoostedSpecies?: readonly SpeciesId[];
-  boostFusions?: boolean; //MODIFIER REWORK PLEASE
+  readonly boostFusions?: boolean; //MODIFIER REWORK PLEASE
-  classicWaveRewards?: EventWaveReward[]; // Rival battle rewards
+  readonly classicWaveRewards?: readonly EventWaveReward[]; // Rival battle rewards
-  trainerShinyChance?: number; // Odds over 65536 of trainer mon generating as shiny
+  readonly trainerShinyChance?: number; // Odds over 65536 of trainer mon generating as shiny
-  music?: EventMusicReplacement[];
+  readonly music?: readonly EventMusicReplacement[];
-  dailyRunChallenges?: EventChallenge[];
+  readonly dailyRunChallenges?: readonly EventChallenge[];
 }
 
-const timedEvents: TimedEvent[] = [
+const timedEvents: readonly TimedEvent[] = [
   {
     name: "Winter Holiday Update",
     eventType: EventType.SHINY,
@@ -385,7 +385,8 @@ const timedEvents: TimedEvent[] = [
 
 export class TimedEventManager {
   isActive(event: TimedEvent) {
-    return event.startDate < new Date() && new Date() < event.endDate;
+    const now = new Date();
+    return event.startDate < now && now < event.endDate;
   }
 
   activeEvent(): TimedEvent | undefined {
@@ -427,19 +428,17 @@ export class TimedEventManager {
 
   getEventBannerLangs(): string[] {
     const ret: string[] = [];
-    ret.push(...timedEvents.find(te => this.isActive(te) && te.availableLangs != null)?.availableLangs!);
+    ret.push(...(timedEvents.find(te => this.isActive(te) && te.availableLangs != null)?.availableLangs ?? []));
     return ret;
   }
 
   getEventEncounters(): EventEncounter[] {
     const ret: EventEncounter[] = [];
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te))
+      if (this.isActive(te) && te.eventEncounters != null) {
-      .map(te => {
+        ret.push(...te.eventEncounters);
-        if (te.eventEncounters != null) {
+      }
-          ret.push(...te.eventEncounters);
+    }
-        }
-      });
     return ret;
   }
 
@@ -472,13 +471,11 @@ export class TimedEventManager {
    */
   getDelibirdyBuff(): string[] {
     const ret: string[] = [];
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te))
+      if (this.isActive(te) && te.delibirdyBuff != null) {
-      .map(te => {
+        ret.push(...te.delibirdyBuff);
-        if (te.delibirdyBuff != null) {
+      }
-          ret.push(...te.delibirdyBuff);
+    }
-        }
-      });
     return ret;
   }
 
@@ -488,39 +485,35 @@ export class TimedEventManager {
    */
   getWeather(): WeatherPoolEntry[] {
     const ret: WeatherPoolEntry[] = [];
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te))
+      if (this.isActive(te) && te.weather != null) {
-      .map(te => {
+        ret.push(...te.weather);
-        if (te.weather != null) {
+      }
-          ret.push(...te.weather);
+    }
-        }
-      });
     return ret;
   }
 
   getAllMysteryEncounterChanges(): EventMysteryEncounterTier[] {
     const ret: EventMysteryEncounterTier[] = [];
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te))
+      if (this.isActive(te) && te.mysteryEncounterTierChanges != null) {
-      .map(te => {
+        ret.push(...te.mysteryEncounterTierChanges);
-        if (te.mysteryEncounterTierChanges != null) {
+      }
-          ret.push(...te.mysteryEncounterTierChanges);
+    }
-        }
-      });
     return ret;
   }
 
   getEventMysteryEncountersDisabled(): MysteryEncounterType[] {
     const ret: MysteryEncounterType[] = [];
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te) && te.mysteryEncounterTierChanges != null)
+      if (this.isActive(te) && te.mysteryEncounterTierChanges != null) {
-      .map(te => {
+        for (const metc of te.mysteryEncounterTierChanges) {
-        te.mysteryEncounterTierChanges?.map(metc => {
           if (metc.disable) {
             ret.push(metc.mysteryEncounter);
           }
-        });
+        }
-      });
+      }
+    }
     return ret;
   }
 
@@ -529,15 +522,15 @@ export class TimedEventManager {
     normal: MysteryEncounterTier,
   ): MysteryEncounterTier {
     let ret = normal;
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te) && te.mysteryEncounterTierChanges != null)
+      if (this.isActive(te) && te.mysteryEncounterTierChanges != null) {
-      .map(te => {
+        for (const metc of te.mysteryEncounterTierChanges) {
-        te.mysteryEncounterTierChanges?.map(metc => {
           if (metc.mysteryEncounter === encounterType) {
             ret = metc.tier ?? normal;
           }
-        });
+        }
-      });
+      }
+    }
     return ret;
   }
 
@@ -551,15 +544,16 @@ export class TimedEventManager {
   }
 
   getEventLuckBoostedSpecies(): SpeciesId[] {
-    const ret: SpeciesId[] = [];
+    const ret = new Set<SpeciesId>();
-    timedEvents
+
-      .filter(te => this.isActive(te))
+    for (const te of timedEvents) {
-      .map(te => {
+      if (this.isActive(te) && te.luckBoostedSpecies != null) {
-        if (te.luckBoostedSpecies != null) {
+        for (const s of te.luckBoostedSpecies) {
-          ret.push(...te.luckBoostedSpecies.filter(s => !ret.includes(s)));
+          ret.add(s);
         }
-      });
+      }
-    return ret;
+    }
+    return Array.from(ret);
   }
 
   areFusionsBoosted(): boolean {
@@ -574,45 +568,50 @@ export class TimedEventManager {
    */
   getFixedBattleEventRewards(wave: number): string[] {
     const ret: string[] = [];
-    timedEvents
+    for (const te of timedEvents) {
-      .filter(te => this.isActive(te) && te.classicWaveRewards != null)
+      if (this.isActive(te) && te.classicWaveRewards != null) {
-      .map(te => {
+        ret.push(...te.classicWaveRewards.filter(cwr => cwr.wave === wave).map(cwr => cwr.type));
-        ret.push(...te.classicWaveRewards!.filter(cwr => cwr.wave === wave).map(cwr => cwr.type));
+      }
-      });
+    }
     return ret;
   }
 
-  // Gets the extra shiny chance for trainers due to event (odds/65536)
+  /**
+   * Get the extra shiny chance for trainers due to event
+   */
   getClassicTrainerShinyChance(): number {
     let ret = 0;
-    const tsEvents = timedEvents.filter(te => this.isActive(te) && te.trainerShinyChance != null);
+    for (const te of timedEvents) {
-    tsEvents.map(t => (ret += t.trainerShinyChance!));
+      const shinyChance = te.trainerShinyChance;
+      if (shinyChance && this.isActive(te)) {
+        ret += shinyChance;
+      }
+    }
     return ret;
   }
 
   getEventBgmReplacement(bgm: string): string {
     let ret = bgm;
-    timedEvents.map(te => {
+    for (const te of timedEvents) {
       if (this.isActive(te) && te.music != null) {
-        te.music.map(mr => {
+        for (const mr of te.music) {
           if (mr[0] === bgm) {
             console.log(`it is ${te.name} so instead of ${mr[0]} we play ${mr[1]}`);
             ret = mr[1];
           }
-        });
+        }
       }
-    });
+    }
     return ret;
   }
 
   /**
-   * Activates any challenges on {@linkcode globalScene.gameMode} for the currently active event
+   * Activate any challenges on {@linkcode globalScene.gameMode} for the currently active event
    */
   startEventChallenges(): void {
-    const challenges = this.activeEvent()?.dailyRunChallenges;
+    for (const eventChal of this.activeEvent()?.dailyRunChallenges ?? []) {
-    challenges?.forEach((eventChal: EventChallenge) =>
+      globalScene.gameMode.setChallengeValue(eventChal.challenge, eventChal.value);
-      globalScene.gameMode.setChallengeValue(eventChal.challenge, eventChal.value),
+    }
-    );
   }
 }
 

src/ui/handlers/pokedex-page-ui-handler.ts

@@ -240,8 +240,8 @@ export class PokedexPageUiHandler extends MessageUiHandler {
   private passive: AbilityId;
   private hasPassive: boolean;
   private hasAbilities: number[];
-  private biomes: BiomeTierTod[];
+  private biomes: readonly BiomeTierTod[];
-  private preBiomes: BiomeTierTod[];
+  private preBiomes: readonly BiomeTierTod[];
   private baseStats: number[];
   private baseTotal: number;
   private evolutions: SpeciesFormEvolution[];
@@ -893,7 +893,7 @@ export class PokedexPageUiHandler extends MessageUiHandler {
   }
 
   // Function to ensure that forms appear in the appropriate biome and tod
-  sanitizeBiomes(biomes: BiomeTierTod[], speciesId: number): BiomeTierTod[] {
+  sanitizeBiomes(biomes: readonly BiomeTierTod[], speciesId: number): readonly BiomeTierTod[] {
     if (speciesId === SpeciesId.BURMY || speciesId === SpeciesId.WORMADAM) {
       return biomes.filter(b => {
         const formIndex = (() => {

src/utils/speed-order.ts

@@ -16,22 +16,23 @@ interface hasPokemon {
  * @returns The sorted array of {@linkcode Pokemon}
  */
 export function sortInSpeedOrder<T extends Pokemon | hasPokemon>(pokemonList: T[], shuffleFirst = true): T[] {
-  pokemonList = shuffleFirst ? shufflePokemonList(pokemonList) : pokemonList;
+  if (shuffleFirst) {
+    shufflePokemonList(pokemonList);
+  }
   sortBySpeed(pokemonList);
   return pokemonList;
 }
 
 /**
+ * Shuffle the list of pokemon *in place*
  * @param pokemonList - The array of Pokemon or objects containing Pokemon
- * @returns The shuffled array
+ * @returns The same array instance that was passed in, shuffled.
  */
 function shufflePokemonList<T extends Pokemon | hasPokemon>(pokemonList: T[]): T[] {
   // This is seeded with the current turn to prevent an inconsistency where it
   // was varying based on how long since you last reloaded
   globalScene.executeWithSeedOffset(
-    () => {
+    () => randSeedShuffle(pokemonList),
-      pokemonList = randSeedShuffle(pokemonList);
-    },
     globalScene.currentBattle.turn * 1000 + pokemonList.length,
     globalScene.waveSeed,
   );