From f12ebf405e924bf909e3dfb4410cf5a7ada16eb5 Mon Sep 17 00:00:00 2001
From: Caleb White <cdwhite3@pm.me>
Date: Wed, 19 Jun 2024 13:24:11 -0500
Subject: [PATCH] fix: improve performance and robustness of
 Relation::getMorphAlias()

---
 src/Illuminate/Database/Eloquent/Relations/Relation.php | 4 ++--
 tests/Database/DatabaseEloquentRelationTest.php         | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Illuminate/Database/Eloquent/Relations/Relation.php b/src/Illuminate/Database/Eloquent/Relations/Relation.php
index cba4ca2afed0..d94671d4f777 100755
--- a/src/Illuminate/Database/Eloquent/Relations/Relation.php
+++ b/src/Illuminate/Database/Eloquent/Relations/Relation.php
@@ -505,11 +505,11 @@ public static function getMorphedModel($alias)
      * Get the alias associated with a custom polymorphic class.
      *
      * @param  string  $className
-     * @return int|string|null
+     * @return int|string
      */
     public static function getMorphAlias(string $className)
     {
-        return array_flip(static::$morphMap)[$className] ?? null;
+        return array_search($className, static::$morphMap, strict: true) ?: $className;
     }
 
     /**
diff --git a/tests/Database/DatabaseEloquentRelationTest.php b/tests/Database/DatabaseEloquentRelationTest.php
index 47bd92710bcf..0fac8f8d3b7f 100755
--- a/tests/Database/DatabaseEloquentRelationTest.php
+++ b/tests/Database/DatabaseEloquentRelationTest.php
@@ -239,8 +239,8 @@ public function testGetMorphAlias()
     {
         Relation::morphMap(['user' => 'App\User']);
 
-        $this->assertEquals('user', Relation::getMorphAlias('App\User'));
-        $this->assertNull(Relation::getMorphAlias('Does\Not\Exist'));
+        $this->assertSame('user', Relation::getMorphAlias('App\User'));
+        $this->assertSame('Does\Not\Exist', Relation::getMorphAlias('Does\Not\Exist'));
     }
 
     public function testWithoutRelations()