Template inheritance with multiple children renders incorrect data

wimski commented 11 months ago

Laravel Version

10.10.33

PHP Version

8.2.4

Database Driver & Version

No response

Description

When using template inheritance with @yield and @section by multiple children at the same time, only the data of the first child will be rendered. The other children will therefore show the data of the first child (in the inherited template). I would expect that every child template would be rendered with its own data.

I've created a repository to demonstrate the issue (also see 'Steps To Reproduce'). The last commit gives a clear picture of the setup. I've included three examples which all use the same template inheritance setup:

Simple Blade Includes
View Components
Livewire

https://github.com/wimski/laravel-view-inheritance-issue/commit/d2e6257bc8add924e4a59f5fb71504201a4139b2

Steps To Reproduce

Copy .env.example to .env.

Run the following commands:

git clone git@github.com:wimski/laravel-view-inheritance-issue.git
cd laravel-view-inheritance-issue
make setup

Visit http://localhost:8000 to view the issue.
Notice that in the actual results the second item always has concreteValue: bar (from the first item) instead of concreteValue: ipsum.

crynobone commented 11 months ago

Hey there,

While this may be a legitimate issue, can you first try posting your problem or question on one of the support channels below? If this issue can be definitively identified as a bug, feel free to open up a new issue with a link to the original one and we'll gladly help you out.

Thanks!

wimski commented 11 months ago

@crynobone I managed to fix 'my' issue like this:

https://github.com/wimski/laravel-view-inheritance-issue/commit/e2587a8c2f1e804aef9a97f1c2327f2396c2e8fe

use Illuminate\View\View as BaseView;

class View extends BaseView
{
    public function render(callable $callback = null): string
    {
        $contents = parent::render();

        $this->factory->flushSections();

        return $contents;
    }
}

Apparently all the section contents are cached during the entire request cycle, which results in incorrect data usage in rendering when you have multiple views extending the same parent in one page (request cycle). I resolved this by flushing the section cache after the rendering of each individual view (within the page/request cycle).

So either it's not a bug because extending views was always only intended to be used for a single view (a page), or it is. If the former is the case, a big disclaimer in the documentation would be nice so the limitations of extending are clear.

The fact that sections are cached by name during the rendering of an entire page, can have some weird effects if you use the same section names in different (unrelated) views. This consequence is also not mentioned in the documentation. And I'm wondering if that was ever an intended consequence.

EDIT

Okay, this results in errors for certain more complex setups :thinking:

laravel / framework