Since 1.4.9, setting class prop of type Set to the result of Set#reduce makes PHPStan think a TypeError is possible, regardless of the native types of the reducer callback. #6791
Description
Bug report
Starting with PHPStan 1.4.9 (it didn't happen in 1.4.8), when implicitThrows and missingCheckedExceptionInThrows are enabled, the attached code snippet reports this error:
Function setFooProp() throws checked exception TypeError but it's missing from the PHPDoc @throws tag.
✏️ lib/Utils/Foo.php
I expect the PHPDoc above the anonymous function to be ignored, but surely the native return type should make it clear that TypeError will never be thrown here.
Code snippet that reproduces the problem
https://phpstan.org/r/9846cab9-33a1-461c-91bb-3f418bdfaf09
(Can't reproduce the error in the playground since it requires enabling stuff in the PHPStan config file.)
Expected output
No errors should be reported.