[8.x] @aware blade directive

[inxilpro]

This is a re-submit of #39080 that makes the data from any components that are actively being rendered as well as parent components that haven't yet been rendered available to child components via the @consume directive:

{{-- menu.blade.php --}}
@props(['color'])
<ul>
  <x-menu-item color="orange">A</x-menu-item>
  <x-menu-item>B</x-menu-item>
  {{ $slot }}
</ul>

{{-- menu-item.blade.php --}}
@consume(['color' => 'red'])
<li>slot={{ $slot }}, color={{ $color }}</li>

{{-- Without setting color attribute, colors will be: orange, red, blue, red --}}
<x-menu>
  <x-menu-item color="blue">C</x-menu-item>
  <x-menu-item>D</x-menu-item>
</x-menu>

{{-- With setting color attribute, colors will be: orange, pink, blue, pink --}}
<x-menu color="pink">
  <x-menu-item color="blue">C</x-menu-item>
  <x-menu-item>D</x-menu-item>
</x-menu>

[taylorotwell]

Heh, didn't know you were working on this again and actually just submitted a PR with another approach.

Let me know what you think: https://github.com/laravel/framework/pull/39102/files

[inxilpro]

Hm. What do you expect the output of my tests to be? With your implementation, I'm expecting:

<ul>
<li>slot=Inline child 1, color=orange</li>
<li>slot=Inline child 2, color=pink</li>
<li>slot=Default item 1, color=blue</li>
<li>slot=Default item 2, color=pink</li>
</ul>

But actually getting:

<ul>
<li>slot=Inline child 1, color=orange</li>
<li>slot=Inline child 2, color=orange</li>
<li>slot=Default item 1, color=blue</li>
<li>slot=Default item 2, color=blue</li>
</ul>

It feels like you should be able to explicitly override consumed data. A use case may be:

<x-menu style="muted">
  <x-menu.item>About</x-menu.item>
  <x-menu.item>Contact</x-menu.item>
  <x-menu.item style="danger">Log Out</x-menu.item>
</x-menu>

[taylorotwell]

@inxilpro can you pull in my recent flushComponent stuff on 8.x into this branch?

[inxilpro]

@taylorotwell I just updated the tests. I tried to merge yours and mine together so that they covered all the possible cases. Let me know if you have an issue with that. I'll pull in the flushComponent bit shortly.

[inxilpro]

There are two things that I thought of that might need consideration before merge.

The first is my comment on the docs PR — defaults set in the @props directive are not available to the @aware directive. They need to be set in both places.

The second is whether we want to add an $aware property to Illuminate\View\Component that gets merged along with public properties and methods, so that you can do:

class MenuItem extends Component
{
  public $aware = ['color' => 'gray'];

  // ...
}

[inxilpro]

(I can't really think of any reasonable way to get around the @props issue. The parent's view can't be evaluated until its children are.)

[taylorotwell]

@inxilpro I don't think those are major issues. I personally would not add an $aware property at the moment. The @props default issue we will just have to document.

[driftingly]

@inxilpro are you able to update the name/description of this PR to match the @consume => @aware rename?

[thewebartisan7]

With component class you still use @aware directive in view right?