explodorama / files / test / sprites.test.ts

sprites.test.ts

1	import { readdirSync, readFileSync } from 'node:fs'
2	import { join } from 'node:path'
3	import { describe, expect, it } from 'vitest'
4
5	/** A PNG's width and height, from its IHDR chunk. */
6	function pngSize(file: string): string {
7	const png = readFileSync(file)
8	return `${png.readUInt32BE(16)} × ${png.readUInt32BE(20)}`
9	}
10
11	describe('board sprites', () => {
12	// LittleJS cuts a 128 × 128 tile out of each board texture (render/sprites.ts). A 100 px file
13	// gave an invalid tile, which crashed the game when a Freeze drop was drawn (2026-10-23).
14	for (const dir of ['assets/kenney', 'assets/composed']) {
15	it(`every PNG in ${dir} is 128 × 128`, () => {
16	const wrong = readdirSync(dir)
17	.filter((f) => f.endsWith('.png'))
18	.map((f) => `${f}: ${pngSize(join(dir, f))}`)
19	.filter((line) => !line.endsWith('128 × 128'))
20	expect(wrong).toEqual([])
21	})
22	}
23	})