CachedParser: use LRU cache

[janedbal]

No description provided.

[phpstan-bot]

You've opened the pull request against the latest branch 1.11.x. If your code is relevant on 1.10.x and you want it to be released sooner, please rebase your pull request and change its target to 1.10.x.

[staabm]

But the time difference is unmeasurable here. Who knows if some codebase with complex huge files might cause measurable differences or not.

did you compare before and after with the lowered capacity?
Did you have a look at memory consumption of both impls?

[janedbal]

Did you habe a look at memory consumption of both impls?

Only by seeing what PHPStan reports in -vvv mode. No changes.

Did you compare before and after with the lowered capacity?

PHPStan itself uses lowered capacity (128 instead of default 256) and that is what I tested (results above). I did not do any tests on our huge codebase yet.

[staabm]

Yeah… my point was more about: in case we can reduce the capacity of the cache with this PR, it might be useful because even if it is equal fast, it might save memory

[staabm]

it might make sense to try SplFixedArray here

[staabm]

Hmm our capacity is too small for it beeing useful

https://stackoverflow.com/a/11831076

[janedbal]

After all, it seems like time & cache-miss & memory difference is very small.

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So the only benefit of this MR might be the code readability & test improvement. I can replace the LRUCache with old logic. Would you merge it after that @ondrejmirtes? Or just close it.

[ondrejmirtes]

Yeah, I don't think this fixes a real problem :)