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Author: ker0x

reference/constraints/UniqueEntity.rst

@@ -100,6 +100,27 @@ between all of the rows in your user table:
             }
         }
 
+        // src/Form/Type/UserType.php
+        namespace App\Form\Type;
+
+        use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+
+        class UserType extends AbstractType
+        {
+            // ...
+
+            public function configureOptions(OptionsResolver $resolver): void
+            {
+                $resolver->setDefaults([
+                    // ...
+                    'data_class' => User::class,
+                    'constraints' => [
+                        new UniqueEntity(fields: ['email']),
+                    ],
+                ]);
+            }
+        }
+
 .. warning::
 
     This constraint doesn't provide any protection against `race conditions`_.
@@ -116,8 +137,9 @@ between all of the rows in your user table:
 Using a PHP class
 -----------------
 
-This constraint can also check **uniqueness on any PHP class** and not only on
-Doctrine entities. Consider the following Doctrine entity::
+This constraint can also check **uniqueness on any PHP class** that is mapped to
+a Doctrine entity, and not only on Doctrine entities. Consider the following
+Doctrine entity::
 
     // src/Entity/User.php
     namespace App\Entity;
@@ -160,8 +182,6 @@ following using the `entityClass`_ option:
         )]
         class UserDto
         {
-            public ?int $id = null,
-
             #[Assert\Email]
             public ?string $email = null;
         }
@@ -208,8 +228,6 @@ following using the `entityClass`_ option:
 
         class UserDto
         {
-            public ?int $id = null;
-
             public ?string $email = null;
 
             public static function loadValidatorMetadata(ClassMetadata $metadata): void
@@ -353,7 +371,7 @@ the combination value is unique (e.g. two users could have the same email,
 as long as they don't have the same name also).
 
 If you need to require two fields to be individually unique (e.g. a unique
-``email`` and a unique ``username``), you should use two ``UniqueEntity`` entries,
+``email`` and a unique ``username``), you must use two ``UniqueEntity`` entries,
 each with a single field.
 
 When `using a PHP class`_, the names of the unique fields may differ
@@ -721,6 +739,10 @@ a key-value mapping:
             }
         }
 
+.. note::
+
+    This option has no effect when the constraint is applied to an entity.
+
 ``message``
 ~~~~~~~~~~~