Wrote test and added documentation

src/data/battler-tags.ts

@@ -969,14 +969,20 @@ export class EncoreTag extends MoveRestrictionBattlerTag {
     }
   }
 
-  public isMoveRestricted(move: Moves, user?: Pokemon): boolean {
+  /**
+   * Checks if the move matches the moveId stored within the tag and returns a boolean value
+   * @param move {@linkcode Moves} the move selected
+   * @param user {@linkcode Pokemon}
+   * @returns `true` if the move does not match with the moveId stored and as a result, restricted
+   */
+  override isMoveRestricted(move: Moves, _user?: Pokemon): boolean {
     if (move !== this.moveId) {
       return true;
     }
     return false;
   }
 
-  selectionDeniedText(pokemon: Pokemon, move: Moves): string {
+  override selectionDeniedText(_pokemon: Pokemon, move: Moves): string {
     return i18next.t("battle:moveDisabled", { moveName: allMoves[move].name });
   }
 

src/test/moves/encore.test.ts

@@ -0,0 +1,59 @@
+import { BattlerTagType } from "#app/enums/battler-tag-type";
+import { BattlerIndex } from "#app/battle";
+import { Abilities } from "#enums/abilities";
+import { Moves } from "#enums/moves";
+import { Species } from "#enums/species";
+import GameManager from "#test/utils/gameManager";
+import Phaser from "phaser";
+import { afterEach, beforeAll, beforeEach, describe, expect, it } from "vitest";
+
+describe("Moves - Encore", () => {
+  let phaserGame: Phaser.Game;
+  let game: GameManager;
+
+  beforeAll(() => {
+    phaserGame = new Phaser.Game({
+      type: Phaser.HEADLESS,
+    });
+  });
+
+  afterEach(() => {
+    game.phaseInterceptor.restoreOg();
+  });
+
+  beforeEach(() => {
+    game = new GameManager(phaserGame);
+    game.override
+      .ability(Abilities.BALL_FETCH)
+      .battleType("single")
+      .disableCrits()
+      .enemySpecies(Species.MAGIKARP)
+      .enemyAbility(Abilities.BALL_FETCH)
+      .enemyMoveset(Moves.SPLASH);
+  });
+
+  it("Pokemon under both Encore and Torment should alternate between Struggle and restricted move", async () => {
+    const turnOrder = [ BattlerIndex.ENEMY, BattlerIndex.PLAYER ];
+    game.override.moveset([ Moves.ENCORE, Moves.TORMENT, Moves.SPLASH ]);
+    await game.classicMode.startBattle([ Species.FEEBAS ]);
+
+    const enemyPokemon = game.scene.getEnemyPokemon();
+    game.move.select(Moves.ENCORE);
+    await game.setTurnOrder(turnOrder);
+    await game.phaseInterceptor.to("BerryPhase");
+    expect(enemyPokemon?.getTag(BattlerTagType.ENCORE)).toBeDefined();
+
+    await game.toNextTurn();
+    game.move.select(Moves.TORMENT);
+    await game.setTurnOrder(turnOrder);
+    await game.phaseInterceptor.to("BerryPhase");
+    expect(enemyPokemon?.getTag(BattlerTagType.TORMENT)).toBeDefined();
+
+    await game.toNextTurn();
+    game.move.select(Moves.SPLASH);
+    await game.setTurnOrder(turnOrder);
+    await game.phaseInterceptor.to("BerryPhase");
+    const lastMove = enemyPokemon?.getLastXMoves()[0];
+    expect(lastMove?.move).toBe(Moves.STRUGGLE);
+  });
+});