test/GameControlsServiceTest.js

const assert = require('chai').assert;
const Direction = require('../app/models/direction');
const Player = require('../app/models/player');
const GameControlsService = require('../app/services/game-controls-service');

describe('GameControlsService', () => {
    'use strict';

    it('should get valid next moves when moving up', done => {
        const nextMoves = GameControlsService.getValidNextMove(Direction.UP);
        assert.deepEqual(nextMoves, [Direction.LEFT, Direction.RIGHT]);
        done();
    });

    it('should get valid next moves when moving down', done => {
        const nextMoves = GameControlsService.getValidNextMove(Direction.DOWN);
        assert.deepEqual(nextMoves, [Direction.LEFT, Direction.RIGHT]);
        done();
    });

    it('should get valid next moves when moving left', done => {
        const nextMoves = GameControlsService.getValidNextMove(Direction.LEFT);
        assert.deepEqual(nextMoves, [Direction.UP, Direction.DOWN]);
        done();
    });

    it('should get valid next moves when moving right', done => {
        const nextMoves = GameControlsService.getValidNextMove(Direction.RIGHT);
        assert.deepEqual(nextMoves, [Direction.UP, Direction.DOWN]);
        done();
    });

    it('should handle directional key downs and change player direction', done => {
        const player = new Player();
        player.direction = Direction.RIGHT;
        player.directionBeforeMove = Direction.RIGHT;
        let keyCode = 38; // Up arrow
        GameControlsService.handleKeyDown(player, keyCode);
        assert.equal(player.direction, Direction.UP);

        keyCode = 40; // Down arrow
        GameControlsService.handleKeyDown(player, keyCode);
        assert.equal(player.direction, Direction.DOWN);

        player.directionBeforeMove = Direction.UP;
        keyCode = 37; // Left arrow
        GameControlsService.handleKeyDown(player, keyCode);
        assert.equal(player.direction, Direction.LEFT);

        keyCode = 39; // Right arrow
        GameControlsService.handleKeyDown(player, keyCode);
        assert.equal(player.direction, Direction.RIGHT);
        done();
    });

    it('should not handle a non-directional key down', done => {
        const player = new Player();
        player.direction = Direction.RIGHT;
        player.directionBeforeMove = Direction.RIGHT;
        const keyCode = 82; // r
        GameControlsService.handleKeyDown(player, keyCode);
        assert.equal(player.direction, Direction.RIGHT);
        done();
    });
});