feat: add $Uint8ArrayLike

Author: joshunrau

src/__tests__/zod.test.ts

@@ -3,7 +3,7 @@ import * as module from 'node:module';
 import { describe, expect, it } from 'vitest';
 import { z } from 'zod';
 
-import { $BooleanLike, $NumberLike, $UrlLike, isZodType } from '../zod.js';
+import { $BooleanLike, $NumberLike, $Uint8ArrayLike, $UrlLike, isZodType } from '../zod.js';
 
 const require = module.createRequire(import.meta.url);
 
@@ -84,3 +84,35 @@ describe('$UrlLike', () => {
     expect(result.data).toBeInstanceOf(URL);
   });
 });
+
+describe('$Uint8ArrayLike', () => {
+  it('should pass when given a Uint8Array', () => {
+    const input = new Uint8Array([1, 2, 3]);
+    const result = $Uint8ArrayLike.parse(input);
+    expect(result).toBeInstanceOf(Uint8Array);
+    expect([...result]).toEqual([1, 2, 3]);
+  });
+
+  it('should convert an array to Uint8Array', () => {
+    const input = [4, 5, 6];
+    const result = $Uint8ArrayLike.parse(input);
+    expect(result).toBeInstanceOf(Uint8Array);
+    expect([...result]).toEqual([4, 5, 6]);
+  });
+
+  it('should fail to convert an invalid array', () => {
+    expect($Uint8ArrayLike.safeParse([-1, 2, 3]).success).toBe(false);
+    expect($Uint8ArrayLike.safeParse([1, 2, 256]).success).toBe(false);
+    expect($Uint8ArrayLike.safeParse([1, 2, NaN]).success).toBe(false);
+  });
+
+  it('should convert an ArrayBuffer to Uint8Array', () => {
+    const buffer = new ArrayBuffer(3);
+    const view = new Uint8Array(buffer);
+    view.set([7, 8, 9]);
+    const result = $Uint8ArrayLike.safeParse(buffer);
+    expect(result.success).toBe(true);
+    expect(result.data).toBeInstanceOf(Uint8Array);
+    expect([...result.data!]).toEqual([7, 8, 9]);
+  });
+});

src/zod.ts

@@ -42,3 +42,12 @@ export const $UrlLike: z.ZodType<URL, z.ZodTypeDef, any> = z.preprocess(
     .url()
     .transform((arg) => new URL(arg))
 );
+
+export const $Uint8ArrayLike: z.ZodType<Uint8Array, z.ZodTypeDef, any> = z
+  .union([z.array(z.number().int().min(0).max(255)), z.instanceof(Uint8Array), z.instanceof(ArrayBuffer)])
+  .transform((arg) => {
+    if (!(arg instanceof Uint8Array)) {
+      return new Uint8Array(arg);
+    }
+    return arg;
+  });