Questions about Rector's cache

[ondrejmirtes]

Question

Hi, I've seen some mentions about cache in the source code, namely Option::CACHE_DIR and ChangedFilesDetector. I'd like to know what's the purpose of this cache? When does it get hit?

I'm asking because what I'd like to do is to have fast downgrade run when there are very little changes in the code. Because Rector mostly does the same thing over and over again.

So I'd like to have a cache where there's a structure like "path to file" => {original contents, downgraded contents}. When Rector runs, and sees that the file still has the original content, it doesn't have to execute all the expensive and slow logic, it can just replace the contents of the file with downgraded contents from the cache.

I can build it myself, I'd just like to know if there's something like that already in Rector, and how to use it.

Thanks.

[TomasVotruba]

Hi, it seems this cache is hit in 2 steps:

• one for dynamic source locator for sharing files from Rector to PHPStan https://github.com/rectorphp/rector-src/blob/main/src/Console/Command/ProcessCommand.php#L98-L99
• another for processing files https://github.com/rectorphp/rector-src/blob/main/src/Console/Command/ProcessCommand.php#L107-L108

I'm asking because what I'd like to do is to have fast downgrade run when there are very little changes in the code. Because Rector mostly does the same thing over and over again.

That's how it should work. If it's not the case, there is probably some bug.

So I'd like to have a cache where there's a structure like "path to file" => {original contents, downgraded contents}. When Rector runs, and sees that the file still has the original content, it doesn't have to execute all the expensive and slow logic, it can just replace the contents of the file with downgraded contents from the cache.

👍

[TomasVotruba]

After writing this comment, I realize it's important that this whole cache is invalidated on rector.php config file change. It includes all the imported configs as well.

https://github.com/rectorphp/rector-src/blob/e546dbb45f59843b1a81685be05e5e1fb58b6ed9/packages/Caching/Detector/ChangedFilesDetector.php#L91