feat: support enums in Choice constraints

bpolaszek · bpolaszek · commit 1bb884d78c3b · 2021-09-16T10:04:54.000+02:00
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)];
+        }
     }
 
     /**

Original file line number	Diff line number	Diff line change
`@@ -35,7 +35,7 @@ public function validate($value, Constraint $constraint)`
`35`	`35`	`throw new UnexpectedTypeException($constraint, Choice::class);`
`36`	`36`	`}`
`37`	`37`
`38`		`- if (!\is_array($constraint->choices) && !$constraint->callback) {`
	`38`	`+ if (!\is_array($constraint->choices) && !is_a($constraint->choices, \BackedEnum::class, true) && !$constraint->callback) {`
`39`	`39`	`throw new ConstraintDefinitionException('Either "choices" or "callback" must be specified on constraint Choice.');`
`40`	`40`	`}`
`41`	`41`
`@@ -55,6 +55,13 @@ public function validate($value, Constraint $constraint)`
`55`	`55`	`throw new ConstraintDefinitionException('The Choice constraint expects a valid callback.');`
`56`	`56`	`}`
`57`	`57`	`$choices = $choices();`
	`58`	`+ } elseif (is_a($constraint->choices, \BackedEnum::class, true)) {`
	`59`	`+ $choices = array_map(`
	`60`	`+ function (\BackedEnum $enum) {`
	`61`	`+ return $enum->value;`
	`62`	`+ },`
	`63`	`+ $constraint->choices::cases()`
	`64`	`+ );`
`58`	`65`	`} else {`
`59`	`66`	`$choices = $constraint->choices;`
`60`	`67`	`}`
Original file line number	Diff line number	Diff line change
`@@ -16,6 +16,7 @@`
`16`	`16`	`use Symfony\Component\Validator\Exception\ConstraintDefinitionException;`
`17`	`17`	`use Symfony\Component\Validator\Exception\UnexpectedValueException;`
`18`	`18`	`use Symfony\Component\Validator\Test\ConstraintValidatorTestCase;`
	`19`	`+use Symfony\Component\Validator\Test\SampleBackedEnum;`
`19`	`20`
`20`	`21`	`function choice_callback()`
`21`	`22`	`{`
`@@ -93,6 +94,10 @@ public function provideConstraintsWithChoicesArray(): iterable`
`93`	`94`	`if (\PHP_VERSION_ID >= 80000) {`
`94`	`95`	`yield 'named arguments' => [eval('return new \Symfony\Component\Validator\Constraints\Choice(choices: ["foo", "bar"]);')];`
`95`	`96`	`}`
	`97`	`+`
	`98`	`+ if (\PHP_VERSION_ID >= 80100) {`
	`99`	`+ yield 'enums' => [new Choice(SampleBackedEnum::class)];`
	`100`	`+ }`
`96`	`101`	`}`
`97`	`102`
`98`	`103`	`/**`