Observer: fake closures

[SammyK]

Methods are not observed from closures created via Closure::fromCallable() because it creates a fake closure. The observer API explicitly cannot observe fake closures because the observer handlers are stored in the runtime cache of op_arrays.

I haven't figured out an obvious solution yet so I thought I'd throw this out there in case anyone has any good ideas. :)

@derickr: @morrisonlevi shared your use case with me and I think this is the root issue as to why RouterListener->onKernelFinishRequest isn't being observed. It looks like it's being called after being converted into a fake closure in the EventDispatcher.

[SammyK]

TIL that the ext/zend_test tests are no longer running in CI. 🤔

[SammyK]

It looks like we might have access to the original runtime cache if we "unwrap" the fake closure in _zend_observe_fcall_begin. I'll tinker with this a bit more next week.

[nikic]

TIL that the ext/zend_test tests are no longer running in CI.

It might be that they never actually ran ... The problem seems to be that the extension is located in ext/zend_test but reports its name as zend-test.

[nikic]

I've opened #6613 to change the extension name, which should also result in the tests being run.

[SammyK]

It might be that they never actually ran

They were running in TravisCI but I think exclusively so.

I'll be rebasing this now that #6613 is merged (thanks again Nikita!) and start digging into this again later in the week (most likely on Friday).

[dstogov]

I also got into the same problem with skipping fake closures.
May be, I suggested to do this myself, but I can't remember the reason or reproduce any problems.

[dstogov]

After some testing, I think we may remove ZEND_ACC_FAKE_CLOSURE limitation.

[SammyK]

@dstogov Thanks for checking this out. I tried to track back why we avoided fake closures when adding the API but couldn't find the source. At any rate, the tests are passing now so I think this should be good to go. :)