LinkGenerator: accept classname in $dest

[mabar]

• new feature
• BC break? no

This is minimal change needed in Nette in order to support NOT using mapping and to reference class directly instead.

$this->linkGenerator->link(self::class . ':default');

To fully support that behavior also a class_exists() check is needed in PresenterFactory. Without this is my change untestable, so let me know if I should modify also PresenterFactory and write tests.
https://github.com/orisai/nette-application/blob/73906f0f3009f751c15d8170467246957ca2e239/src/Mapping/DefaultPresenterFactory.php#L147-L163

I am already able to achieve it with $this->presenter->link($this->presenter::class . ':default');.

Benefit of this change is presenters don't have to follow any namespace structure, just like any class.

[dg]

There should be a condition that always makes it clear whether it is a class or a presenter, otherwise it could get awkward. For example, a class must contain at least one character \.

[mabar]

I wrote an regex which expects [[Class\Name:]action] [#fragment] and all the tests on regex101.com work (check the unit tests tab). But I cannot get it work in PHP, it does not match my test string App\Admin\User\List\UserListPresenter:default, not sure why :/
https://regex101.com/r/u2DneV/1

[mabar]

Okay, got it. Had to add some character classes. Seems like regex101 does not use php, just PCRE2 - regex with [\\] and \\ works with regex101, [\\\] works with php