Mockable.php

<?php

class Mockable {
  public $constructorArgs;
  public $cloned;
  public function __construct($arg1 = NULL, $arg2 = NULL) {
    $this->constructorArgs = array(
      $arg1,
      $arg2,
    );
  }
  public function mockableMethod() {

    // something different from NULL
    return TRUE;
  }
  public function anotherMockableMethod() {

    // something different from NULL
    return TRUE;
  }
  public function __clone() {
    $this->cloned = TRUE;
  }

}