Hello,
I would like to ask your advice about the following error that appeared after checking a (custom) module.
Thank you in advance for your help.
Hi Lucie
Thanks for reaching out!
You are not the only one experiencing this, and we have flagged this on our end accordingly.
It is first and foremost important to note that this is actually not related to the module itself, nor is it necessarily a problem for your website reaching Drupal 9 compatibility. PHPStan (https://phpstan.org/) is a tool which automatically scans your PHP code. The error you are seeing says that PHPStan failed to run because drush_log() was previously declared.
As we are still working on identifying and resolving this particular issue, we request affected website owners to submit a ticket to create a test website of the website(s) in question. You can do so here: https://cern.service-now.com/service-portal?id=sc_cat_item&name=Drupal-Clone&se=Drupal-Service.
We will then proceed by upgrading the test website to Drupal 9, giving you a chance to verify that everything looks the way it should. If all goes well, we will then upgrade your production website. This is based on the assumption, and current working hypothesis, that this particular issue does not impact your Drupal 9 compatibility.
We will of course be available throughout the process should you have any concerns or questions.
Thanks!