Extend assert

assert-ext.js

const assert = require('assert');

// Wrap `assert()`
const assertExt = (val, msg) => assert(val, msg);

// Extend assert properties
Object.assign(assertExt, assert, {
	someCustomAssertion: require('./assert/some-custom-assertion')
});

module.exports = assertExt;

Automagical version:

const assert = require('assert');
const fs = require('fs');
const path = require('path');

const EXT_DIR = path.join(__dirname, 'assert');

// Load extensions from EXT_DIR
const extensions = fs.readdirSync(EXT_DIR)
  .reduce((exts, fname) => Object.assign(exts, {
    [path.basename(fname, '.js')]: require(path.join(EXT_DIR, fname))
  }), {});

// Extend assert
const assertClone = assert.bind(null);
Object.assign(assertClone, assert, extensions);

module.exports = assertClone;