错误信息：

Call to undefined method PHP_CodeCoverage_Filter::getInstance()

第一种：

If you have problems with accessing components try another way. 

sudo apt - get install php - pear 

Install  phpunit  by using pear. 

pear config - set auto_discover 1 pear install pear . phpunit . de / PHPUnit

Install  phpunit /Selenium, but first you need to install  curl  module 

sudo apt - get install php5 - curl 

sudo apt-get remove phpunit 

sudo pear channel-discover pear.phpunit.de 

sudo pear channel-discover pear.symfony-project.com 

sudo pear channel-discover components.ez.no 

sudo pear update-channels 

sudo pear upgrade-all 

sudo pear install --alldeps phpunit/PHPUnit 

sudo pear install --force --alldeps phpunit/PHPUnit