node/test/parallel/test-child-process-send-utf8.js

'use strict';
const common = require('../common');
const assert = require('assert');
const fork = require('child_process').fork;

const expected = Array(1e5).join('ßßßß');
if (process.argv[2] === 'child') {
  process.send(expected);
} else {
  const child = fork(process.argv[1], ['child']);
  child.on('message', common.mustCall((actual) => {
    assert.strictEqual(actual, expected);
  }));
}