扩展 PHPUnit_Framework_TestCase 的不可测试基类

I have a series of related test cases for which I have created a base class that contains some common tests to be inherited by all test cases:

BaseClass_TestCase.php:
class BaseClass_TestCase extends PHPUnit_Framework_TestCase { 
  function test_common() {
    // Test that should be run for all derived test cases
  }
}

MyTestCase1Test.php:
include 'BaseClass_TestCase.php';
class MyTestCase1 extends BaseClass_TestCase {
    function setUp() {
      // Setting up
    }
    function test_this() {
      // Test particular to MyTestCase1
    }
}

MyTestCase2Test.php:
include 'BaseClass_TestCase.php';
class MyTestCase2 extends BaseClass_TestCase {
    function setUp() {
      // Setting up
    }
    function test_this() {
      // Test particular to MyTestCase2
    }
}

我的问题是，当我尝试运行文件夹中的所有测试时，它失败了(没有输出).