Gist do post "Usando PHPUnit no Codeigniter via Hooks" Link: http://willmendesnetoprojects.wordpress.com/2013/02/24/usando-phpunit-no-codeigniter-via-hooks/

phpunit.xml.dist

<?xml version="1.0" encoding="UTF-8"?>

<phpunit
    colors="true"
    stopOnFailure="false"
    backupGlobals="false"
    backupStaticAttributes="false"
    convertErrorsToExceptions="true"
    convertNoticesToExceptions="true"
    convertWarningsToExceptions="true"
    processIsolation="false"
    syntaxCheck="false"
    cacheTokens="true"
    verbose="false"
    bootstrap="tests/Bootstrap.php">
    <testsuites>
        <testsuite name="CITools Test Suite">
            <directory>./tests/</directory>
        </testsuite>
    </testsuites>
    <filter>
        <whitelist>
            <directory>./system/</directory>
        </whitelist>
    </filter>
</phpunit>