False positive "Access to an uninitialized readonly property"

[PsyonixDan]

Bug report

This specific false positive happens if a constructor creates a callback/closure, and that closure calls a method which accesses the readonly property.

These are the full requirements for the bug to be seen:

• A class has a readonly property.
• The property is set in the constructor.
• A method accesses that property.
• A callback/closure which calls the method is created in the constructor.

This bug started with version 1.10.23 and is still being reported with the latest version. The error isn't reported in earlier versions.

Code snippet that reproduces the problem

https://phpstan.org/r/9590d157-89fd-4d1f-8290-a7af4f82d461

Expected output

PHP shouldn't report an error.

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