Just asking, is the library on the server, where its supposed to be and phabricator has some error causing it not to see it or is the library just fully not there?

I had this issue with attempting the last Phabricator update on my own install and the files were there.

Upgrading to Phorge did not cause it.

This error could also be caused if Phabricator was updated but not Arcanist, or vice versa. The error is output here https://github.com/phacility/phabricator/blob/9426765a2c6a149f5b0ed2d9132cd1e4e7ee152d/scripts/init/lib.php#L14

https://gerrit.wikimedia.org/r/plugins/gitiles/phabricator/antivandalism/+/6b59a3cd9e6170ff6797494187be98915e1985c7%5E!/ triggered this at end of June 2023. I naively wonder if https://gerrit.wikimedia.org/r/plugins/gitiles/phabricator/antivandalism/+/refs/heads/wmf/stable/src/.phutil_module_cache was involved as I added two new function calls... but really no clue, just a super vague idea. Could also be scap which I know nothing about ofc.

I had that thought, but things run correctly after a php restart, so I assumed it was a red herring.

I'm unclear if .phutil_module_cache gets generated on its own or requires an arc liberate call…

https://secure.phabricator.com/book/phabcontrib/article/adding_new_classes/

This will write three files:

• src/.phutil_module_cache This is a cache which makes "arc liberate" faster when you run it to update the library. You can safely remove it at any time. If you check your library into version control, you can add this file to ignore rules (like .gitignore).
• src/__phutil_library_init__.php This records the name of the library and tells libphutil that a library exists here.
• src/__phutil_library_map__.php This is a map of all the symbols (functions and classes) in the library, which allows them to be autoloaded at runtime and dependencies to be statically managed by arc liberate.

The latter makes it sound like arc liberate would need to be run if functions change, but I suppose this might only be relevant if it's something that needs to be autoloaded externally to the class, which if I remember right your change probably doesn't?

Change 956486 had a related patch set uploaded (by Brennen Bearnes; author: Brennen Bearnes):

[operations/puppet@production] phabricator deployment: restart php when finalizing deploy

https://gerrit.wikimedia.org/r/956486

Change 956486 merged by Jelto:

[operations/puppet@production] phabricator deployment: restart php when finalizing deploy

https://gerrit.wikimedia.org/r/956486

In T314460#8973969, @brennen wrote:

I'm unclear if .phutil_module_cache gets generated on its own or requires an arc liberate call…

For the records, as I run into the same question in T342041, we removed that file at least in extensions in rPHEX04f637010f634301159838b6e06b3e457d8c1981