Fix PHP 8.1 "strlen(null)" exception which blocks rendering most applications' Configure pages
strlen() was used in Phabricator to check if a generic value is a non-empty string.
This behavior is deprecated since PHP 8.1. Phorge adopts phutil_nonempty_string() as a replacement.
Note: this may highlight other absurd input values that might be worth correcting
instead of just ignoring. If phutil_nonempty_string() throws an exception in your
instance, report it to Phorge to evaluate and fix that specific corner case.
Added also a small inline documentation to better leave what I find.
Applied this change change and way more applications' Configure pages finally rendered in web browser.
For example, /applications/view/PhabricatorAuditApplication/ is now correctly rendered.
(However, some pages expose followup exceptions to be handled in separate tasks.)
Reviewers: O1 Blessed Committers, valerio.bozzolan
Reviewed By: O1 Blessed Committers, valerio.bozzolan
Subscribers: speck, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno
Maniphest Tasks: T15358
Differential Revision: https://we.phorge.it/D25197