plainauthcas doesn't play nicely with authsplit

[moobyfr]

plainauthcas play difficulty with the plugin splitauth (which permit to separate authentication from authorization with groups)
my current setup is:
$conf['authtype'] = 'authsplit';
$conf['plugin']['authsplit']['primary_authplugin'] = 'authplaincas';
$conf['plugin']['authsplit']['secondary_authplugin'] = 'authmysql';
the authpllaincas only check the CAS ticket , the others values (name, email, ...) and groups are computed by the authmysql plugin
This setup is usefull if the CAS server return very few attributes (in my case, only the login)

• the main problem is: Groups are replaced by authplaincas after there were set by the secondary plugin
  auth.php:314 if ($this->_userInfo['grps'] != $this->_userInfo['tmp_grps'] ... (and the name and the email)

• a minor problem is the direct check from the plugin as auth backend which makes display the link to the cas server or not
  action.php:54 if ($conf['authtype'] == 'authplaincas')

[phy25]

@moobyfr I cannot reproduce your first issue on a similar test environment with authpdo, authplaincas and authsplit working together, and that seems unlikely to happen as what I see in the code. You may turn on debug config for authsplit to see what's going on indeed.

For the latter one that's easy to fix 😄 Will make a PR for that.