Unfortunately, PHPUnit does not work out of the box on Ubuntu 11.04 through apt-get. We also need to use PEAR to install the dependencies.

The Problem

The standard approach is to simply use apt-get or pear to install everything:

$ sudo apt-get install phpunit

After installing the package, you will most likely receive the following error:

PHP Fatal error: require_once(): Failed opening required 'PHP/CodeCoverage/Filter.php' (include_path='.:/usr/share/php:/usr/share/pear') in /usr/bin/phpunit on line 38

Installing Dependencies

Obviously, we're missing a few dependencies as shown in the previous error. Fortunately, PEAR provides the --alldeps flag while installing so that we automatically download and install dependencies that are necessary.

Upgrade PEAR First

There's one more problem: Ubuntu 11.04 comes with PEAR version 1.9.1 when we need version 1.9.2 for all dependencies to install. Before we go any further, we need to upgrade PEAR:

$ sudo pear upgrade pear

Install PHPUnit Dependencies

Now, we can install PHPUnit and it's dependencies through PEAR.

$ sudo pear channel-discover pear.phpunit.de
$ sudo pear channel-discover components.ez.no
$ sudo pear channel-discover pear.symfony.com
$ sudo pear install --alldeps phpunit/PHPUnit

Make Sure It Works

After everything is complete, verify that phpunit works:

$ phpunit --version
PHPUnit 3.5.5 by Sebastian Bergmann.

Have fun unit testing with PHPUnit.