feat: support enums in Choice constraints

symfony · bpolaszek · Sep 16, 2021 · Sep 16, 2021 · Sep 17, 2021 · Sep 16, 2021
commit 1f9a3a115890b1436e6b228793e29a92bf7e5e5e
diff --git a/src/Symfony/Component/Validator/CHANGELOG.md b/src/Symfony/Component/Validator/CHANGELOG.md
@@ -5,6 +5,7 @@ CHANGELOG
 ---

 * Add support for `ConstraintViolationList::createFromMessage()`
+ * Add enum support (>= PHP 8.1) for the `Choice` constraint

 5.3
 ---

diff --git a/src/Symfony/Component/Validator/Constraints/ChoiceValidator.php b/src/Symfony/Component/Validator/Constraints/ChoiceValidator.php
@@ -35,7 +35,7 @@ public function validate($value, Constraint $constraint)
            throw new UnexpectedTypeException($constraint, Choice::class);
        }

-        if (!\is_array($constraint->choices) && !$constraint->callback) {
+        if (!\is_array($constraint->choices) && !is_a($constraint->choices, \BackedEnum::class, true) && !$constraint->callback) {
            throw new ConstraintDefinitionException('Either "choices" or "callback" must be specified on constraint Choice.');
        }

@@ -55,6 +55,13 @@ public function validate($value, Constraint $constraint)
                throw new ConstraintDefinitionException('The Choice constraint expects a valid callback.');
            }
            $choices = $choices();
+        } elseif (is_a($constraint->choices, \BackedEnum::class, true)) {
+            $choices = array_map(
+                function (\BackedEnum $enum) {
+                    return $enum->value;
+                },
+                $constraint->choices::cases()
+            );
        } else {
            $choices = $constraint->choices;
        }

diff --git a/src/Symfony/Component/Validator/Test/SampleBackedEnum.php b/src/Symfony/Component/Validator/Test/SampleBackedEnum.php
@@ -0,0 +1,20 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Symfony\Component\Validator\Test;
+
+enum SampleBackedEnum: string
+{
+    case FOO = 'foo';
+    case BAR = 'bar';
+}
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/ChoiceValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/ChoiceValidatorTest.php
@@ -16,6 +16,7 @@
 use Symfony\Component\Validator\Exception\ConstraintDefinitionException;
 use Symfony\Component\Validator\Exception\UnexpectedValueException;
 use Symfony\Component\Validator\Test\ConstraintValidatorTestCase;
+use Symfony\Component\Validator\Test\SampleBackedEnum;

 function choice_callback()
 {
@@ -93,6 +94,10 @@ public function provideConstraintsWithChoicesArray(): iterable
        if (\PHP_VERSION_ID >= 80000) {
            yield 'named arguments' => [eval('return new \Symfony\Component\Validator\Constraints\Choice(choices: ["foo", "bar"]);')];
        }
+
+        if (\PHP_VERSION_ID >= 80100) {
+            yield 'enums' => [new Choice(SampleBackedEnum::class)];
+        }
    }

    /**