Serialization of 'Closure' is not allowed when using Model::automaticallyEagerLoadRelationships() and caching

[broqit]

Laravel Version

12.8.1

PHP Version

8.4.5

Database Driver & Version

8.0.31

Description

After adding the following line to the AppServiceProvider’s boot() method:
`use Illuminate\Database\Eloquent\Model;

public function boot(): void
{
Model::automaticallyEagerLoadRelationships();
}`

an error occurs when trying to cache a model collection or API resource:

Serialization of 'Closure' is not allowed

This happens even when caching plain model collections like:

Cache::remember('key', 3600, fn () => Model::with('relation')->get());

or:

Cache::remember('key', 3600, fn () => MyResource::collection(Model::with('relation')->get())->resolve());

Steps To Reproduce

1.	Add Model::automaticallyEagerLoadRelationships(); in your AppServiceProvider::boot()
2.	Attempt to cache an Eloquent model collection or API Resource
3.	See this error:

Serialization of 'Closure' is not allowed

[litvinchuk]

I think #55345 has solved this
but a new version of Laravel hasn't been released with this changes.

[gabrielrbarbosa]

Just had this in production, this should have been release as a minor version as it is a fatal error...

[AndrewMast]

@taylorotwell Hate to ping, but we've had three issues (#55378, #55360, and #55354) opened for this issue that has already been fixed and merged three days ago in PR #55345. We need a new release please 😅

[iammuttaqi]

went to create a PR on this. but the issue has already been fixed. hats off! 👏
eagerly waiting for a new release..

[AndrewMast]

@broqit @gabrielrbarbosa Just pinging you to let you know the fix was released this morning in v12.9.0!