[11.x] Adds Model::casts() method and named static methods for built-in casters (#47237)

* Adds `Model::casts()` method

* Apply fixes from StyleCI

* Adds `AsCollection::using`

* Adds `AsEncryptedCollection::using`

* Adds `AsEnumArrayObject::using`

* Adjusts tests

* Fixes docs

* Adds `AsEnumCollection::using`

* Adds array format support

* Tests priority

* Tests serialization

* Method name

* Fixes single element in array

* Fixes single element in array

* formatting

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

Co-authored-by: Enzo Innocenzi <[email protected]>

* Adjusts changes after rebase

---------

Co-authored-by: StyleCI Bot <[email protected]>
Co-authored-by: Taylor Otwell <[email protected]>
Co-authored-by: Enzo Innocenzi <[email protected]>

Author: 4 people

src/Illuminate/Database/Eloquent/Casts/AsCollection.php

@@ -46,4 +46,15 @@ public function set($model, $key, $value, $attributes)
             }
         };
     }
+
+    /**
+     * Specify the collection for the cast.
+     *
+     * @param  class-string  $class
+     * @return string
+     */
+    public static function using($class)
+    {
+        return static::class.':'.$class;
+    }
 }

src/Illuminate/Database/Eloquent/Casts/AsEncryptedCollection.php

@@ -49,4 +49,15 @@ public function set($model, $key, $value, $attributes)
             }
         };
     }
+
+    /**
+     * Specify the collection for the cast.
+     *
+     * @param  class-string  $class
+     * @return string
+     */
+    public static function using($class)
+    {
+        return static::class.':'.$class;
+    }
 }

src/Illuminate/Database/Eloquent/Casts/AsEnumArrayObject.php

@@ -81,4 +81,15 @@ protected function getStorableEnumValue($enum)
             }
         };
     }
+
+    /**
+     * Specify the Enum for the cast.
+     *
+     * @param  class-string  $class
+     * @return string
+     */
+    public static function of($class)
+    {
+        return static::class.':'.$class;
+    }
 }

src/Illuminate/Database/Eloquent/Casts/AsEnumCollection.php

@@ -77,4 +77,15 @@ protected function getStorableEnumValue($enum)
             }
         };
     }
+
+    /**
+     * Specify the Enum for the cast.
+     *
+     * @param  class-string  $class
+     * @return string
+     */
+    public static function of($class)
+    {
+        return static::class.':'.$class;
+    }
 }

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

@@ -182,6 +182,18 @@ trait HasAttributes
      */
     public static $encrypter;
 
+    /**
+     * Initialize the trait.
+     *
+     * @return void
+     */
+    protected function initializeHasAttributes()
+    {
+        $this->casts = $this->ensureCastsAreStringValues(
+            array_merge($this->casts, $this->casts()),
+        );
+    }
+
     /**
      * Convert the model's attributes to an array.
      *
@@ -719,11 +731,39 @@ protected function mutateAttributeForArray($key, $value)
      */
     public function mergeCasts($casts)
     {
+        $casts = $this->ensureCastsAreStringValues($casts);
+
         $this->casts = array_merge($this->casts, $casts);
 
         return $this;
     }
 
+    /**
+     * Ensure that the given casts are strings.
+     *
+     * @param  array  $casts
+     * @return array
+     */
+    protected function ensureCastsAreStringValues($casts)
+    {
+        foreach ($casts as $attribute => $cast) {
+            $casts[$attribute] = match (true) {
+                is_array($cast) => value(function () use ($cast) {
+                    if (count($cast) === 1) {
+                        return $cast[0];
+                    }
+
+                    [$cast, $arguments] = [array_shift($cast), $cast];
+
+                    return $cast.':'.implode(',', $arguments);
+                }),
+                default => $cast,
+            };
+        }
+
+        return $casts;
+    }
+
     /**
      * Cast an attribute to a native PHP type.
      *
@@ -1521,7 +1561,7 @@ public function hasCast($key, $types = null)
     }
 
     /**
-     * Get the casts array.
+     * Get the attributes that should be cast.
      *
      * @return array
      */
@@ -1534,6 +1574,16 @@ public function getCasts()
         return $this->casts;
     }
 
+    /**
+     * Get the attributes that should be cast.
+     *
+     * @return array
+     */
+    protected function casts()
+    {
+        return [];
+    }
+
     /**
      * Determine whether a value is Date / DateTime castable for inbound manipulation.
      *