A 'virtual properties' attribute

[gwillz]

We already have a very handy UpdateVirtualTrait that lets us apply functions whenever updating data via constructor or update(). This lets us normalise or parse complex data. However, it's a little cumbersome (and broken for strong types).

Attributes

Declare an attribute for properties to define how it should be marshalled into the correct type.

There are three attributes:

• VirtualProperty - this defines a method to call when updating this property.
• VirtualObject - this converts arrays into objects using configurable logic.
• VirtualArray - for create object arrays, same configurable logic.

Such as:

class MyModel extends DataObject
{
   use UpdateTrait;
   use AttributesVirtualTrait;

   #[VirtualProperty('setComplex')]
   public $complex;

   #[VirtualObject(OtherModel::class)]
   public $object;
   
   public function setComplex($value)
   {
      this->complex = new Complex($value);
   }
}

Strong Types

This introduces the UpdateVirtualInterface with a setVirtual() method to replace the wonky applyVirtual() approach.

Where instead of modifying types in-place on the object (which doesn't work with strong types), instead we convert and apply virtual properties first.

The relevant update traits are updated to use the new interface. This is technically a breaking change.

Important considerations

Something like this feels redundant, and you would be right.

#[VirtualObject(SomeModel::class)
public SomeModel $object;

The target object is right there and we could simply use that instead of the attribute. However this scenario is also common:

#[VirtualObject(SomeModel::class)
public BaseModel $object;

Where BaseModel is abstract or an interface.