WordPress different error_reporting level to Drupal / Backdrop

Just putting this here

We are currently having an E2E failure on WordPress v Backdrop / Drupal. The E2E test is specifcally looking at trying to load an invalid asset builder URL and is finding that it is not returning empty, i.e. there is some content coming back when using file_get_contents

WordPress runs generally with the following error_reporting levels

error_reporting( E_CORE_ERROR | E_CORE_WARNING | E_COMPILE_ERROR | E_ERROR | E_WARNING | E_PARSE | E_USER_ERROR | E_USER_WARNING | E_RECOVERABLE_ERROR );

Where as Drupal / Backdrop run as just E_CORE_ERROR iirc

I have proposed 2 sets of fixes for the test

1. Using Guzzle in the test https://github.com/civicrm/civicrm-core/pull/14201
2. overriding the error_reporting level https://github.com/civicrm/civicrm-core/pull/14212

However in both cases that doesn't feel brilliant because we are essentially hiding away the issue that WordPress by default is returning different content to that in Drupal and Backdrop for the same situation (calling an invalid URL)

I tried altering the error_reporting in the part of Civi Code that actualy manages the asset Builder urls but it seemed to not do anything.

Any thoughts?

ping @totten @kcristiano @haystack