有人知道我做错了什么吗?我已经安装了phpunit,当我在/opt/local/PEAR目录下时一切正常,所以如果我进入/opt/local/PEAR目录并运行phpunit,则会得到以下结果:PHPUnit 3.5.11 by Sebastian Bergmann。用法: phpunit [switches] UnitTest [UnitTest.php] phpunit [switches] blablabla,但是如果我在其他路径上,我会得到以下错误信息:Warning: require_once(PHP/CodeCoverage/Filter.php): failed to open stream: No such file or directory in /usr/local/bin/phpunit on line 38 Fatal error: require_once(): Failed opening required 'PHP/CodeCoverage/Filter.php' (include_path='.:/usr/lib/php') in /usr/local/bin/phpunit on line 38。我知道我的PATH出了问题。我该如何解决?