First off, thank you for the package!

I'm not sure if I'm doing this wrong or it's simply not supported but here it is:

Describe the bug
I have a Subscription model that has a morphToMany relation to setting keys (so a many to many polymorphic). The Subscription model is not cacheable and the relation to setting keys looks like this. The Setting model (the pivot) is also not cacheable.

 public function settingKeys(): MorphToMany
 {
 return $this
 ->morphToMany(SettingKey::class, 'settingable', 'settings')
 ->using(Setting::class)
 ->withPivot('value')
 ->withTimestamps();
 }

The SettingKey model on the other hand uses Cachable.

Eloquent Query

This test will fail with Failed asserting that 1 matches expected 0. at the last line:

 ...
 $subscriptionPeriod->settingKeys()->attach($settingKey->id, ['value' => 'something']);
 $this->assertEquals(1, $subscriptionPeriod->settingKeys()->count());
 $subscriptionPeriod->settingKeys()->detach();
 $this->assertEquals(0, $subscriptionPeriod->settingKeys()->count());

This test with disableCache will pass:

 ...
 $subscriptionPeriod->settingKeys()->attach($settingKey->id, ['value' => 'something']);
 $this->assertEquals(1, $subscriptionPeriod->settingKeys()->count());
 $subscriptionPeriod->settingKeys()->detach();
 $this->assertEquals(0, $subscriptionPeriod->settingKeys()->disableCache()->count());

I'm using the array driver for testing. (We do have the file driver in production although it's not officially supported anymore.. I hope to be switching it over to redis soon as we'll need to cache some more things).

Stack Trace
....

Environment

• PHP: 7.4
• OS: Windows 10
• Laravel: 7.28.3
• Model Caching: 0.10.2