Added utils package for parsing helpers

src/utils.test.ts

@@ -0,0 +1,224 @@
+import { describe, expect, it } from 'vitest';
+import {
+  U8,
+  U16,
+  U32,
+  I8,
+  I16,
+  I32,
+  F32,
+  F64,
+  isBytes,
+  assertBytes,
+  bytesToHex,
+  hexToBytes,
+  bytesToBase64,
+  base64ToBytes,
+  decodeBytes,
+  encodeBytes,
+} from './utils';
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+describe('utils', () => {
+  const staticHexVectors = [
+    { bytes: Uint8Array.from([]), hex: '' },
+    { bytes: Uint8Array.from([0xbe]), hex: 'be' },
+    { bytes: Uint8Array.from([0xca, 0xfe]), hex: 'cafe' },
+    { bytes: Uint8Array.from(new Array(1024).fill(0x69)), hex: '69'.repeat(1024) },
+  ];
+
+  const buf = new ArrayBuffer(8);
+  const v8 = new Uint8Array(buf);
+  for (let i = 0; i < v8.length; i++) v8[i] = i + 1;
+
+  it('U8 from ArrayBuffer', () => {
+    const a8 = U8(buf);
+    expect(a8).toBeInstanceOf(Uint8Array);
+    expect(Array.from(a8)).toEqual([1,2,3,4,5,6,7,8]);
+  });
+
+  it('U8 from Uint8Array view', () => {
+    const sub = new Uint8Array(buf, 2, 4);
+    const s8 = U8(sub);
+    expect(Array.from(s8)).toEqual([3,4,5,6]);
+  });
+
+  it('U16 from ArrayBuffer', () => {
+    const a16 = U16(buf);
+    expect(a16).toBeInstanceOf(Uint16Array);
+    expect(a16.length).toBe(Math.floor(buf.byteLength / 2));
+  });
+
+  it('U16 from Uint8Array view', () => {
+    const sub = new Uint8Array(buf, 2, 4);
+    const s16 = U16(sub);
+    expect(s16.length).toBe(Math.floor(sub.byteLength / 2));
+  });
+
+  it('U32 from ArrayBuffer', () => {
+    const a32 = U32(buf);
+    expect(a32).toBeInstanceOf(Uint32Array);
+    expect(a32.length).toBe(Math.floor(buf.byteLength / 4));
+  });
+
+  it('U32 from Uint8Array view', () => {
+    const sub = new Uint8Array(buf, 4, 4);
+    const s32 = U32(sub);
+    expect(s32.length).toBe(Math.floor(sub.byteLength / 4));
+  });
+
+  it('I8 from ArrayBuffer and view', () => {
+    const buf = new ArrayBuffer(4);
+    const dv = new DataView(buf);
+    dv.setInt8(0, -5);
+    dv.setInt8(1, 120);
+    dv.setInt8(2, -128);
+    dv.setInt8(3, 127);
+
+    const a = I8(buf);
+    expect(Array.from(a)).toEqual([-5, 120, -128, 127]);
+
+    const sub = new Int8Array(buf, 1, 2);
+    const s = I8(sub);
+    expect(Array.from(s)).toEqual([120, -128]);
+  });
+
+  it('I16 from ArrayBuffer and misaligned view throws', () => {
+    const buf = new ArrayBuffer(6);
+    const dv = new DataView(buf);
+    dv.setInt16(0, -12345, true);
+    dv.setInt16(2, 12345, true);
+    dv.setInt16(4, 32767, true);
+
+    const a16 = I16(buf);
+    expect(a16.length).toBe(3);
+    expect(a16[0]).toBe(-12345);
+    expect(a16[1]).toBe(12345);
+    expect(a16[2]).toBe(32767);
+
+    const view = new Uint8Array(buf, 1, 4);
+    expect(() => I16(view)).toThrow();
+  });
+
+  it('I32 from ArrayBuffer and misaligned view throws', () => {
+    const buf = new ArrayBuffer(12);
+    const dv = new DataView(buf);
+    dv.setInt32(0, -0x1234567, true);
+    dv.setInt32(4, 0x1234567, true);
+
+    const a32 = I32(buf);
+    expect(a32[0]).toBe(-0x1234567);
+    expect(a32[1]).toBe(0x1234567);
+
+    const view = new Uint8Array(buf, 1, 8);
+    expect(() => I32(view)).toThrow();
+  });
+
+  it('F32/F64 from ArrayBuffer', () => {
+    const buf = new ArrayBuffer(16);
+    const dv = new DataView(buf);
+    dv.setFloat32(0, 3.14, true);
+    dv.setFloat32(4, -2.5, true);
+    dv.setFloat64(8, 1.23456789e3, true);
+
+    const f32 = F32(buf);
+    expect(f32[0]).toBeCloseTo(3.14, 5);
+    expect(f32[1]).toBeCloseTo(-2.5, 5);
+
+    const f64 = F64(buf);
+    expect(f64[1]).toBeCloseTo(1.23456789e3, 8);
+  });
+
+  it('isBytes', () => {
+    expect(isBytes(new Uint8Array([1,2]))).toBe(true);
+    expect(isBytes(new Uint16Array([1,2]) as unknown)).toBe(false);
+    expect(isBytes(new ArrayBuffer(2) as unknown)).toBe(false);
+  })
+
+  it('assertBytes', () => {
+    // assertBytes accepts a Uint8Array
+    expect(() => assertBytes(new Uint8Array([1,2]))).not.toThrow();
+    // assertBytes with length mismatch throws
+    expect(() => assertBytes(new Uint8Array([1,2]), 3)).toThrow();
+    // assertBytes with wrong type throws
+    expect(() => assertBytes(new Uint16Array([1,2]) as any)).toThrow();
+  });
+
+  it('hexToBytes / bytesToHex roundtrip', () => {
+    for (const v of staticHexVectors) {
+      expect(hexToBytes(v.hex)).toEqual(v.bytes);
+      expect(hexToBytes(v.hex.toUpperCase())).toEqual(v.bytes);
+      expect(bytesToHex(v.bytes)).toEqual(v.hex);
+      // encode -> decode
+      const h = bytesToHex(v.bytes);
+      expect(hexToBytes(h)).toEqual(v.bytes);
+    }
+  });
+
+  it('base64 encodings roundtrip and variants', () => {
+    const hello = new Uint8Array([72,101,108,108,111]); // 'Hello'
+    const b64 = bytesToBase64(hello, 'base64');
+    expect(base64ToBytes(b64)).toEqual(hello);
+
+    const b64raw = bytesToBase64(hello, 'base64raw');
+    expect(base64ToBytes(b64raw)).toEqual(hello);
+
+    const b64url = bytesToBase64(hello, 'base64url');
+    expect(base64ToBytes(b64url)).toEqual(hello);
+
+    const b64urlraw = bytesToBase64(hello, 'base64urlraw');
+    expect(base64ToBytes(b64urlraw)).toEqual(hello);
+  });
+
+  it('encodeBytes / decodeBytes round robin across encodings', () => {
+    const bytes = Uint8Array.from([0xde,0xad,0xbe,0xef]);
+    const encodings = ['hex','base64','base64raw','base64url','base64urlraw'] as const;
+    for (const enc of encodings) {
+      const s = encodeBytes(bytes, enc as any);
+      const out = decodeBytes(s, enc as any);
+      expect(out).toEqual(bytes);
+    }
+  });
+
+  it('throws on invalid inputs for hex/base64 decoders', () => {
+    expect(() => hexToBytes('z')).toThrow();
+    expect(() => base64ToBytes('??')).toThrow();
+    expect(() => decodeBytes('abc', 'unsupported' as any)).toThrow();
+  });
+
+  it('edge cases: offsets, odd lengths, url base64, empty and large roundtrips', () => {
+    // U16/U32 with subarray offset
+    const buf = new ArrayBuffer(6);
+    const v = new Uint8Array(buf);
+    v.set([1,2,3,4,5,6]);
+    const view = new Uint8Array(buf, 1, 4); // [2,3,4,5]
+    const u8 = U8(view);
+    expect(Array.from(u8)).toEqual([2,3,4,5]);
+    // Unaligned views cannot be reinterpreted as 16-bit/32-bit arrays on some
+    // platforms; U16/U32 will throw for misaligned offsets. Assert that behavior.
+    expect(() => U16(view)).toThrow();
+
+    // hexToBytes with odd length should throw
+    expect(() => hexToBytes('f')).toThrow();
+
+    // base64 url-safe without padding should be accepted
+    const sample = new Uint8Array([0x01,0x02,0x03,0xff]);
+    const raw = bytesToBase64(sample, 'base64raw');
+    // url variant
+    const url = bytesToBase64(sample, 'base64urlraw');
+    expect(base64ToBytes(raw)).toEqual(sample);
+    expect(base64ToBytes(url)).toEqual(sample);
+
+    // empty inputs
+    expect(bytesToHex(new Uint8Array([]))).toBe('');
+    expect(bytesToBase64(new Uint8Array([]), 'base64')).toBe('');
+
+    // large random roundtrip
+    const large = new Uint8Array(10000);
+    for (let i = 0; i < large.length; i++) large[i] = i & 0xff;
+    const h = bytesToHex(large);
+    expect(hexToBytes(h)).toEqual(large);
+    const b64 = bytesToBase64(large, 'base64raw');
+    expect(base64ToBytes(b64)).toEqual(large);
+  });
+});