fix: Php 8.1 support (#53)

* Updated league/fractal to 0.20.0. Updated Fractal::jsonSerialize return type to match the JsonSerializable interface. Updated TraversableClass::getIterator() to match the IteratorAggregate interface.

* Updated php minimum supported version from 7.3 to 7.4

* Updated `ArraySerializer::collection` type hints

* Resolved issues with broken tests.

Author: AlexJezior

composer.json

@@ -19,8 +19,8 @@
         }
     ],
     "require": {
-        "php": "^7.3|^8.0",
-        "league/fractal": "^0.19.0"
+        "php": "^7.4|^8.0",
+        "league/fractal": "^0.20.0"
     },
     "require-dev": {
         "illuminate/pagination": "~5.3.0|~5.4.0",

src/ArraySerializer.php

@@ -14,7 +14,7 @@ class ArraySerializer extends BaseArraySerializer
      *
      * @return array
      */
-    public function collection($resourceKey, array $data)
+    public function collection(string $resourceKey, array $data): array
     {
         return $data;
     }

src/Fractal.php

@@ -455,7 +455,7 @@ public function getResourceName()
     /**
      * Convert the object into something JSON serializable.
      */
-    public function jsonSerialize()
+    public function jsonSerialize(): mixed
     {
         return $this->toArray();
     }

tests/TestTransformer.php

@@ -11,7 +11,7 @@ class TestTransformer extends TransformerAbstract
      *
      * @var array
      */
-    protected $availableIncludes = [
+    protected array $availableIncludes = [
         'characters',
         'publisher',
     ];

tests/TestTransformerWithIncludes.php

@@ -11,7 +11,7 @@ class TestTransformerWithIncludes extends TransformerAbstract
      *
      * @var array
      */
-    protected $defaultIncludes = [
+    protected array $defaultIncludes = [
         'characters',
         'publisher',
         'title',

tests/TraversableClass.php

@@ -4,6 +4,7 @@
 
 use ArrayIterator;
 use IteratorAggregate;
+use Traversable;
 
 class TraversableClass implements IteratorAggregate
 {
@@ -18,7 +19,7 @@ public function __construct(array $items)
     /**
      * @return array
      */
-    public function getIterator()
+    public function getIterator(): Traversable
     {
         return new ArrayIterator($this->items);
     }