const assert = require('assert');

class BankCustomer {
  constructor(name, pinInput) {
    let privateName = name;
    let privatePinInput = pinInput;
    this.getName = () => privateName;
    this.verifyPinInput = () => privatePinInput;
  }
}

const customer = new BankCustomer('John Doe', '3579');
assert.equal(typeof customer.getName, 'function');
assert.equal(typeof customer.verifyPinInput, 'function');
assert.equal(customer.getName(), 'John Doe');
assert.ok(customer.verifyPinInput('3579'));