u8

.devcontainer/devcontainer.json

@@ -0,0 +1,13 @@
+{
+  "$schema": "https://raw.githubusercontent.com/devcontainers/spec/refs/heads/main/schemas/devContainer.schema.json",
+  "name": "node",
+  "image": "mcr.microsoft.com/devcontainers/javascript-node:4.0.5-trixie",
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "editorconfig.editorconfig"
+      ]
+    }
+  },
+  "postCreateCommand": "sudo npm install -g npm-check-updates"
+}

.github/workflows/node.js.yml

@@ -11,13 +11,13 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [20, 22, 24]
+        node-version: [20, 22, 24, 25]
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           submodules: true
       - name: Install pnpm

.gitignore

@@ -1,3 +1,4 @@
+.pnpm-store/
 coverage/
 docs/
 lib/

eslint.config.js

@@ -5,6 +5,11 @@ import jts from '@cto.af/eslint-config/jsdoc_ts.js';
 import markdown from '@cto.af/eslint-config/markdown.js';
 import ts from '@cto.af/eslint-config/ts.js';
 
+ts[1].settings.n.typescriptExtensionMap = [
+  ['.js', '.js'],
+  ['.ts', '.ts'],
+];
+
 export default [
   {
     ignores: [

package.json

@@ -6,8 +6,11 @@
   "files": [
     "lib/*"
   ],
+  "exports": {
+    ".": "./lib/index.mjs",
+    "u8": "./lib/u8.mjs"
+  },
   "type": "module",
-  "keywords": [],
   "author": "Joe Hildebrand <joe-github@cursive.net>",
   "license": "MIT",
   "repository": {
@@ -29,18 +32,18 @@
     "build": "npm run test && npm run lint && npm run docs && npm pack --dry-run"
   },
   "devDependencies": {
-    "@cto.af/eslint-config": "6.1.0",
+    "@cto.af/eslint-config": "6.2.1",
     "@eslint/markdown": "7.5.1",
-    "@types/node": "24.10.1",
+    "@types/node": "25.0.2",
     "c8": "10.1.3",
-    "eslint": "9.39.1",
-    "eslint-plugin-jsdoc": "61.2.0",
-    "tsdown": "^0.16.3",
-    "typedoc": "0.28.14",
+    "eslint": "9.39.2",
+    "eslint-plugin-jsdoc": "61.5.0",
+    "tsdown": "^0.17.4",
+    "typedoc": "0.28.15",
     "typescript": "5.9.3",
-    "typescript-eslint": "8.46.4"
+    "typescript-eslint": "8.49.0"
   },
-  "packageManager": "pnpm@10.22.0",
+  "packageManager": "pnpm@10.25.0",
   "engines": {
     "node": ">=20"
   }

src/u8.ts

@@ -0,0 +1,26 @@
+import * as impl from './u8Impl.ts';
+
+/**
+ * Convert hex string to bytes.
+ *
+ * @param str String.
+ * @returns Buffer.
+ */
+const hexToU8: (s: string) => Uint8Array =
+  // @ts-expect-error fromHex not in types yet
+  Uint8Array.fromHex as typeof impl.hexToU8 ??
+  impl.hexToU8;
+
+/**
+ * Convert bytes to hex string.
+ * @param u8 Bytes.
+ * @returns Hex.
+ */
+const u8toHex: (u8: Uint8Array) => string =
+  // @ts-expect-error toHex not in types yet
+  Uint8Array.prototype.toHex ? impl.u8toHexModern : impl.u8toHex;
+
+export {
+  hexToU8,
+  u8toHex,
+};

src/u8Impl.ts

@@ -0,0 +1,39 @@
+/**
+ * Convert hex string to bytes.
+ *
+ * @param str String.
+ * @returns Buffer.
+ */
+export function hexToU8(str: string): Uint8Array {
+  str = str.replace(/\s/g, '');
+  let len = Math.ceil(str.length / 2);
+  const res = new Uint8Array(len);
+  len--;
+  for (let end = str.length, start = end - 2;
+    end >= 0;
+    end = start, start -= 2, len--
+  ) {
+    res[len] = parseInt(str.substring(start, end), 16);
+  }
+
+  return res;
+}
+
+/**
+ * Convert bytes to hex string.
+ * @param u8 Bytes.
+ * @returns Hex.
+ */
+export function u8toHex(u8: Uint8Array): string {
+  return u8.reduce((t, v) => t + v.toString(16).padStart(2, '0'), '');
+}
+
+/**
+ * Convert bytes to hex string.
+ * @param u8 Bytes.
+ * @returns Hex.
+ */
+export function u8toHexModern(u8: Uint8Array): string {
+  // @ts-expect-error toHex not in types yet
+  return u8.toHex();
+}

test/u8.test.js

@@ -0,0 +1,26 @@
+import * as impl from '../lib/u8Impl.mjs';
+import {hexToU8, u8toHex} from '../lib/u8.mjs';
+import assert from 'node:assert';
+import test from 'node:test';
+
+test('u8', async () => {
+  await test('u8toHex', () => {
+    const res = u8toHex(new Uint8Array([0, 1, 2, 0xff]));
+    assert.equal(res, '000102ff');
+  });
+
+  await test('u8toHex impl', () => {
+    const res = impl.u8toHex(new Uint8Array([0, 1, 2, 0xff]));
+    assert.equal(res, '000102ff');
+  });
+
+  await test('hexToU8', () => {
+    const res = hexToU8('000102ff');
+    assert.deepEqual(res, new Uint8Array([0, 1, 2, 0xff]));
+  });
+
+  await test('hexToU8 impl', () => {
+    const res = impl.hexToU8('000102ff');
+    assert.deepEqual(res, new Uint8Array([0, 1, 2, 0xff]));
+  });
+});

tsdown.config.js

@@ -4,12 +4,15 @@ export default defineConfig({
   clean: true,
   dts: true,
   entry: [
-    'src/index.ts',
+    'src/*.ts',
   ],
   format: 'esm',
-  minify: true,
+  minify: {
+    mangle: false,
+  },
   outDir: 'lib',
   sourcemap: false,
   splitting: false,
   target: 'es2022',
+  unbundle: true,
 });