Service constructor: add native support for strict array type.

[janbarasek]

Hello,

In the DI service entry, I can request a collection of services that meet the same interface.

For example:

/**
 * @param OrderPaymentGatewayInterface[] $providers
 */
public function __construct(array $providers) { ... }

If I am using PhpStan level 9 and want to specify the exact key type in an array, DIC cannot inject services:

/**
 * @param array<int, OrderPaymentGatewayInterface> $providers
 */
public function __construct(array $providers) { ... }

The challenge is to add native support for composite array notation with exact key definition. In the first phase, I propose to support only the int key type and mark all others as unsupported.

Why support this notation? Much more strict type within the service.

Thanks.

[JanTvrdik]

The keys in $providers are meaningless. Why do you need to ensure that they are integers?

[janbarasek]

Because other application layers can use strict types that expect a service list, for example. Now I have to do this retyping applicationally. Nette could provide the services directly in strict form.

[JanTvrdik]

Can you give example? PhpStan seems to be fine with OrderPaymentGatewayInterface[]
https://phpstan.org/r/89126eed-47d0-4c4d-8536-505ae2fa3a46

[mabar]

I discussed posibility to add a config option to require array keys by PHPStan with Ondrej. Using keys of undefined type is a type-safety loophole which is safer to not allow at all.
Also some coding standard rules require generic type syntax for codebase style consistency, like SlevomatCodingStandard.TypeHints.DisallowArrayTypeHintSyntax

It's not really necesity to have numeric keys in DI services, it would just make working with strictest standards easier.