Laravel: Organizing tests into folders and running them

Is it possible in Laravel to run unit test based on the folder they're placed in?

Currently, the phpunit.xml specifies /tests as the root directory for unit testing:

...
<testsuites>
    <testsuite name="Application Test Suite">
        <directory>./app/tests/</directory>
    </testsuite>
</testsuites>
...

Test are ran via CLI with phpunit command. I would like to organize tests into subfolders, like this:

/tests

• /unit


• /integration

so I can run tests only from the specified subfolder like: phpunit integration.

I tried the above, however the framework assumes that "integration" is the name of a PHP file that doesn't exist.

How do I achieve my goal?