test: add test

Author: kenjis

tests/system/Config/FactoriesTest.php

@@ -321,7 +321,7 @@ public function testCanLoadTwoCellsWithSameShortName()
         $this->assertNotSame($cell1, $cell2);
     }
 
-    public function testDefineTwice()
+    public function testDefineSameAliasTwiceWithDifferentClasses()
     {
         $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage(
@@ -340,6 +340,24 @@ public function testDefineTwice()
         );
     }
 
+    public function testDefineSameAliasAndSameClassTwice()
+    {
+        Factories::define(
+            'models',
+            'CodeIgniter\Shield\Models\UserModel',
+            UserModel::class
+        );
+        Factories::define(
+            'models',
+            'CodeIgniter\Shield\Models\UserModel',
+            UserModel::class
+        );
+
+        $model = model('CodeIgniter\Shield\Models\UserModel');
+
+        $this->assertInstanceOf(UserModel::class, $model);
+    }
+
     public function testDefineNonExistentClass()
     {
         $this->expectException(InvalidArgumentException::class);