Check for variable name in parameters before adding to uses

[bryannielsen]

I hit an issue today in downgrading some Laravel code.
The ArrowFunctionToAnonymousFunctionRector rule would take this function

fn ($deferred) => app(DeferredCallbackCollection::class)[] = $deferred

and transform it to this

function ($deferred) use ($deferred) {
    return app(DeferredCallbackCollection::class)[] = $deferred;
}

and this would result in a PHP error

Fatal error: Cannot use lexical variable $deferred as a parameter name in <file_path>

My patch works well for solving my problem but if there's a better way to fix this that would be great too.
Thanks for your hard work!

[TomasVotruba]

Hi, thanks for the fix. Could you add also failing test fixture, so we have it covered?

[samsonasik]

You can add fixture test at

https://github.com/rectorphp/rector-downgrade-php/tree/main/rules-tests/DowngradePhp74/Rector/ArrowFunction/ArrowFunctionToAnonymousFunctionRector/Fixture

[bryannielsen]

Sorry about that!
I added the test but the only case that was failing before my patch was singleArrayAssignment which mirrors the situation I hit today.

The rest of the cases all worked properly which surprised me so maybe there is a better/different fix that should be made for that case?

[bryannielsen]

@TomasVotruba and @samsonasik I don't understand the last failing check but I'm happy to try and resolve it if you can point me in the right direction. Thanks!