Install instructions seem to indicate it's ok to clone repo into ~/.drush but this doesn't work

[briantully]

I've been using a really old acsf_tools.drush.inc that I think I got many moons ago from Lindsey Catlett. The file was in my ~/.drush folder and seemed to be compatible with both Drush8 and Drush9.

I saw someone share an acsf-tools command that I didn't have, so decided to upgrade acsf-tools and found this repo. Using the older branch of 8.x-dev, I followed the install instructions which state:

For simpler projects with a single developer or very small teams, you can just clone this repository in your users' drush directory (e.g., ~/.drush).

However, this doesn't appear to be true, or if true it seems to require at least Drush 9, which is oddly not a dependency or a requirement, nor is there any warning.

When running drush8 with this repo installed in my ~/.drush directory, I get the following error:

Drush command terminated abnormally due to an unrecoverable error.                                                                 [error]
Error: require(): Failed opening required ''
(include_path='/Users/brian.tully/.composer/vendor/phing/phing/classes:.:/usr/local/Cellar/[email protected]/7.4.16/share/[email protected]/pear') in
/Users/brian.tully/.drush/acsf-tools/acsf_tools.aliases.drushrc.php, line 4

The line in question is:

// Load Composer to get to Symfony components.
$loader = require realpath(__DIR__ . '/../../vendor/autoload.php');

Which seems to indicate a composer requirement that is only supported in Drush 9 since it pulls in Symfony, etc.

Maybe we should update the install instructions to indicate that this is only supported by Drush 9+ ?