Bug report

PHPStan is identifying private constants declared and used in enums as unused.

PHP's manual does mention that Enums support constants:

The following object functionality is available, and behaves just as it does on any other object:

• (...)
• Public, private, and protected constants.
• (...)

And that works just fine: https://3v4l.org/DfldI#v8.2.3

Code snippet that reproduces the problem

https://phpstan.org/r/b7b4a18b-b9c6-4eb1-8ea3-6ad9d2f2e01a

Expected output

No error should be reported.