[8.x] Handle collection creation around a single enum

src/Illuminate/Collections/Traits/EnumeratesValues.php

@@ -16,6 +16,7 @@
 use Symfony\Component\VarDumper\VarDumper;
 use Traversable;
 use UnexpectedValueException;
+use UnitEnum;
 
 /**
  * @property-read HigherOrderCollectionProxy $average
@@ -991,6 +992,8 @@ protected function getArrayableItems($items)
             return (array) $items->jsonSerialize();
         } elseif ($items instanceof Traversable) {
             return iterator_to_array($items);
+        } elseif ($items instanceof UnitEnum) {
+            return [$items];
         }
 
         return (array) $items;

tests/Support/Enums.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Illuminate\Tests\Support;
+
+enum TestEnum
+{
+    case A;
+}
+
+enum TestBackedEnum: int
+{
+    case A = 1;
+}

tests/Support/SupportCollectionTest.php

@@ -24,6 +24,10 @@
 use Symfony\Component\VarDumper\VarDumper;
 use UnexpectedValueException;
 
+if (PHP_VERSION_ID >= 80100) {
+    include_once 'Enums.php';
+}
+
 class SupportCollectionTest extends TestCase
 {
     /**
@@ -4254,6 +4258,26 @@ public function testCollectionFromTraversableWithKeys($collection)
         $this->assertEquals(['foo' => 1, 'bar' => 2, 'baz' => 3], $data->toArray());
     }
 
+    /**
+     * @dataProvider collectionClassProvider
+     * @requires PHP >= 8.1
+     */
+    public function testCollectionFromEnum($collection)
+    {
+        $data = new $collection(TestEnum::A);
+        $this->assertEquals([TestEnum::A], $data->toArray());
+    }
+
+    /**
+     * @dataProvider collectionClassProvider
+     * @requires PHP >= 8.1
+     */
+    public function testCollectionFromBackedEnum($collection)
+    {
+        $data = new $collection(TestBackedEnum::A);
+        $this->assertEquals([TestBackedEnum::A], $data->toArray());
+    }
+
     /**
      * @dataProvider collectionClassProvider
      */