Mark pure function by Psalm

[snapshotpl]

https://psalm.dev/articles/immutability-and-beyond#purity

[moufmouf]

That would be a great idea. Of course, we don't want to do that manually. I guess Psalm has a list of pure PHP functions somewhere in the code. Would you happen to know where it is located?

[snapshotpl]

Just found in https://github.com/vimeo/psalm/tree/master/src/Psalm/Internal/Stubs

@muglug Am I right?

[muglug]

Impure builtin functions are listed here: https://github.com/vimeo/psalm/blob/master/src/Psalm/Internal/Codebase/Functions.php#L280

All others are assumed pure

[moufmouf]

Excellent! Thanks a lot!

[Kharhamel]

#172

[Kharhamel]

@muglug how do you test your function isCallMapFunctionPure() ? Do you use some selected example that you know are pure or impure, or do you have a more general approach?