Avoid doing work before its necessary in mutating scope.

[mad-briller]

Few instances of asking for information before it's really necessary

[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.

[ondrejmirtes]

Thank you!

[mad-briller]

@ondrejmirtes do you think it would be feasible to be able to detect this kind of thing with a custom phpstan rule?

i've written custom rules for single nodes but this would need to check more than one node so i don't know if it's possible, or if it is how i would approach it

as a simple minimum, the rule could be checking for something like "if a variable is assigned and not used before an exit point"

[ondrejmirtes]

Please see this: phpstan/phpstan#8192

But read my last comment too - I was able to solve a bug without CFG even when I thought I needed CFG for that 😊 Maybe it will give you some ideas.

Also bear in mind that the called thing that we move lower needs to be pure/immutable otherwise moving the call might have unintended side effects.

[mad-briller]

okay that gives me something to read and think about, thanks!

great point about purity, luckily phpstan already knows about the concept

[mad-briller]

making changes to NodeScopeResolver isn't possible in an extension, does this mean you would be open to having this kind of rule in phpstan-src itself?

[ondrejmirtes]

I don't understand the question. What kind of changes to the NodeScopeResolver?