[5.5] [WIP] Eloquent object casting

src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php

@@ -35,6 +35,13 @@ trait HasAttributes
      */
     protected $casts = [];
 
+    /**
+     * The attributes that have been cast to classes.
+     *
+     * @var array
+     */
+    protected $classCastCache = [];
+
     /**
      * The attributes that should be mutated to dates.
      *
@@ -70,6 +77,16 @@ trait HasAttributes
      */
     protected static $mutatorCache = [];
 
+    /**
+     * All of the valid primitive cast types.
+     *
+     * @var array
+     */
+    protected static $primitiveCastTypes = [
+        'int', 'integer', 'real', 'float', 'double', 'string', 'bool', 'boolean',
+        'object', 'array', 'json', 'collection', 'date', 'datetime', 'timestamp',
+    ];
+
     /**
      * Convert the model's attributes to an array.
      *
@@ -168,6 +185,10 @@ protected function addCastAttributesToArray(array $attributes, array $mutatedAtt
                 continue;
             }
 
+            if ($this->isClassCastable($key)) {
+                continue;
+            }
+
             // Here we will cast the attribute. Then, if the cast is a date or datetime cast
             // then we will serialize the date for the array. This will convert the dates
             // to strings based on the date format specified for these Eloquent models.
@@ -194,7 +215,7 @@ protected function addCastAttributesToArray(array $attributes, array $mutatedAtt
      */
     protected function getArrayableAttributes()
     {
-        return $this->getArrayableItems($this->attributes);
+        return $this->getArrayableItems($this->getAttributes());
     }
 
     /**
@@ -301,8 +322,7 @@ public function getAttribute($key)
         // If the attribute exists in the attribute array or has a "get" mutator we will
         // get the attribute's value. Otherwise, we will proceed as if the developers
         // are asking for a relationship's value. This covers both types of values.
-        if (array_key_exists($key, $this->attributes) ||
-            $this->hasGetMutator($key)) {
+        if (array_key_exists($key, $this->attributes) || $this->hasGetMutator($key) || $this->isClassCastable($key)) {
             return $this->getAttributeValue($key);
         }
 
@@ -359,8 +379,10 @@ public function getAttributeValue($key)
      */
     protected function getAttributeFromArray($key)
     {
-        if (isset($this->attributes[$key])) {
-            return $this->attributes[$key];
+        $attributes = $this->getAttributes();
+
+        if (isset($attributes[$key])) {
+            return $attributes[$key];
         }
     }
 
@@ -441,7 +463,11 @@ protected function mutateAttribute($key, $value)
      */
     protected function mutateAttributeForArray($key, $value)
     {
-        $value = $this->mutateAttribute($key, $value);
+        if ($this->isClassCastable($key)) {
+            $value = $this->castToClass($key);
+        } else {
+            $value = $this->mutateAttribute($key, $value);
+        }
 
         return $value instanceof Arrayable ? $value->toArray() : $value;
     }
@@ -455,11 +481,13 @@ protected function mutateAttributeForArray($key, $value)
      */
     protected function castAttribute($key, $value)
     {
-        if (is_null($value)) {
+        $castType = $this->getCastType($key);
+
+        if (is_null($value) && in_array($castType, static::$primitiveCastTypes)) {
             return $value;
         }
 
-        switch ($this->getCastType($key)) {
+        switch ($castType) {
             case 'int':
             case 'integer':
                 return (int) $value;
@@ -485,8 +513,61 @@ protected function castAttribute($key, $value)
                 return $this->asDateTime($value);
             case 'timestamp':
                 return $this->asTimestamp($value);
-            default:
-                return $value;
+        }
+
+        if ($this->isClassCastable($key)) {
+            return $this->castToClass($key);
+        }
+
+        return $value;
+    }
+
+    /**
+     * Cast the given attribute to a class.
+     *
+     * @param  string  $key
+     * @return mixed
+     */
+    protected function castToClass($key)
+    {
+        if (isset($this->classCastCache[$key])) {
+            return $this->classCastCache[$key];
+        } else {
+            return $this->classCastCache[$key] = forward_static_call(
+                [$this->getCasts()[$key], 'fromModelAttributes'], $this->attributes, $key, $this
+            );
+        }
+    }
+
+    /**
+     * Determine whether a value is JSON castable for inbound manipulation.
+     *
+     * @param  string  $key
+     * @return bool
+     */
+    protected function isClassCastable($key)
+    {
+        if (! array_key_exists($key, $this->getCasts())) {
+            return false;
+        }
+
+        $class = $this->getCasts()[$key];
+
+        return class_exists($class) && ! in_array($class, static::$primitiveCastTypes);
+    }
+
+    /**
+     * Merge the cast class attributes back into the model.
+     *
+     * @return void
+     */
+    protected function mergeAttributesFromClassCasts()
+    {
+        foreach ($this->classCastCache as $key => $value) {
+            $this->attributes = array_merge(
+                $this->attributes,
+                $value->toModelAttributes($this->attributes, $key, $this)
+            );
         }
     }
 
@@ -537,11 +618,38 @@ public function setAttribute($key, $value)
             return $this->fillJsonAttribute($key, $value);
         }
 
-        $this->attributes[$key] = $value;
+        if ($this->isClassCastable($key)) {
+            $this->setClassCastableAttribute($key, $value);
+        } else {
+            $this->attributes[$key] = $value;
+        }
 
         return $this;
     }
 
+    /**
+     * Set the value of a class castable attribute.
+     *
+     * @param  string  $key
+     * @param  mixed  $value
+     * @return void
+     */
+    protected function setClassCastableAttribute($key, $value)
+    {
+        if (is_null($value)) {
+            $this->attributes = array_merge($this->attributes, array_map(
+                function () {
+                    return null;
+                },
+                $this->castToClass($key)->toModelAttributes($this->attributes, $key, $this)
+            ));
+
+            unset($this->classCastCache[$key]);
+        } else {
+            $this->classCastCache[$key] = $value;
+        }
+    }
+
     /**
      * Determine if a set mutator exists for an attribute.
      *
@@ -850,6 +958,8 @@ protected function isJsonCastable($key)
      */
     public function getAttributes()
     {
+        $this->mergeAttributesFromClassCasts();
+
         return $this->attributes;
     }
 

src/Illuminate/Database/Eloquent/Model.php

@@ -484,6 +484,8 @@ public function push()
      */
     public function save(array $options = [])
     {
+        $this->mergeAttributesFromClassCasts();
+
         $query = $this->newQueryWithoutScopes();
 
         // If the "saving" event returns false we'll bail out of the save and return
@@ -714,6 +716,8 @@ public static function destroy($ids)
      */
     public function delete()
     {
+        $this->mergeAttributesFromClassCasts();
+
         if (is_null($this->getKeyName())) {
             throw new Exception('No primary key defined on model.');
         }
@@ -1338,6 +1342,18 @@ public function __toString()
         return $this->toJson();
     }
 
+     /**
+      * Prepare the object for serialization.
+      *
+      * @return array
+      */
+     public function __sleep()
+     {
+         $this->mergeAttributesFromClassCasts();
+
+         return array_keys(get_object_vars($this));
+     }
+
     /**
      * When a model is being unserialized, check if it needs to be booted.
      *

tests/Database/DatabaseEloquentIntegrationTest.php

@@ -4,6 +4,7 @@
 
 use Exception;
 use PHPUnit\Framework\TestCase;
+use Illuminate\Contracts\Support\Arrayable;
 use Illuminate\Database\Capsule\Manager as DB;
 use Illuminate\Database\Eloquent\Relations\Pivot;
 use Illuminate\Database\Eloquent\Model as Eloquent;
@@ -1061,6 +1062,39 @@ public function testBelongsToManyCustomPivot()
         $this->assertEquals('Jule Doe', $johnWithFriends->friends->find(4)->pivot->friend->name);
     }
 
+    public function testAttributesMayBeCastToValueObjects()
+    {
+        $model = new EloquentTestValueObjectCast;
+        $model->line_one = 'Address Line 1';
+        $model->line_two = 'Address Line 2';
+
+        $this->assertInstanceOf(EloquentTestAddressValueObject::class, $model->address);
+        $this->assertEquals('Address Line 1', $model->address->lineOne);
+        $this->assertEquals('Address Line 2', $model->address->lineTwo);
+
+        $model->address->lineOne = 'Modified Line 1';
+        $this->assertEquals('Modified Line 1', $model->line_one);
+        $this->assertEquals('Modified Line 1', $model->toArray()['line_one']);
+
+        $model->address = new EloquentTestAddressValueObject('Fresh Line 1', 'Fresh Line 2');
+        $this->assertEquals('Fresh Line 1', $model->line_one);
+        $this->assertEquals('Fresh Line 2', $model->line_two);
+
+        $model->address = null;
+        $this->assertNull($model->line_one);
+        $this->assertNull($model->line_two);
+
+        $model->address = new EloquentTestAddressValueObject('Fresh Line 1', 'Fresh Line 2');
+        $model->forceFill(['address' => null]);
+        $this->assertNull($model->line_one);
+        $this->assertNull($model->line_two);
+
+        $model->address = new EloquentTestAddressValueObject('Fresh Line 1', 'Fresh Line 2');
+        $model->address->lineOne = 'Mutated Line 1';
+        $model = unserialize(serialize($model));
+        $this->assertEquals('Mutated Line 1', $model->line_one);
+    }
+
     /**
      * Helpers...
      */
@@ -1273,3 +1307,40 @@ public function level()
         return $this->belongsTo(EloquentTestFriendLevel::class, 'friend_level_id');
     }
 }
+
+class EloquentTestAddressValueObject implements Arrayable
+{
+    public $lineOne;
+    public $lineTwo;
+
+    public function __construct($lineOne, $lineTwo)
+    {
+        $this->lineOne = $lineOne;
+        $this->lineTwo = $lineTwo;
+    }
+
+    public static function fromModelAttributes($attributes)
+    {
+        return new static($attributes['line_one'], $attributes['line_two']);
+    }
+
+    public function toModelAttributes()
+    {
+        return [
+            'line_one' => $this->lineOne,
+            'line_two' => $this->lineTwo,
+        ];
+    }
+
+    public function toArray()
+    {
+        return $this->toModelAttributes();
+    }
+}
+
+class EloquentTestValueObjectCast extends Eloquent
+{
+    protected $casts = [
+        'address' => EloquentTestAddressValueObject::class,
+    ];
+}