[Validator] Fix choice callback option if not array or iterable returned

Author: symfonyaml

src/Symfony/Component/Validator/Constraints/ChoiceValidator.php

@@ -55,6 +55,15 @@ public function validate($value, Constraint $constraint)
                 throw new ConstraintDefinitionException('The Choice constraint expects a valid callback.');
             }
             $choices = $choices();
+            if (is_iterable($choices)) {
+                $choices = iterator_to_array($choices, true);
+            }
+            if (!is_array($choices)) {
+                throw new ConstraintDefinitionException(sprintf(
+                    'The Choice constraint expects the callback to return an iterable value, got %s.',
+                    get_debug_type($choices),
+                ));
+            }
         } else {
             $choices = $constraint->choices;
         }

src/Symfony/Component/Validator/Tests/Constraints/ChoiceValidatorTest.php

@@ -34,6 +34,18 @@ public static function staticCallback()
         return ['foo', 'bar'];
     }
 
+    public static function staticCallbackInvalid()
+    {
+        return null;
+    }
+
+    public static function staticCallbackIterable()
+    {
+        yield 1;
+        yield 2;
+        yield 3;
+    }
+
     public function objectMethodCallback()
     {
         return ['foo', 'bar'];
@@ -185,6 +197,30 @@ public function testInvalidChoice(Choice $constraint)
             ->assertRaised();
     }
 
+    public function testInvalidChoiceCallbackContextMethod()
+    {
+        $this->expectException(ConstraintDefinitionException::class);
+        $this->expectExceptionMessage('The Choice constraint expects the callback to return an iterable value, got null.');
+        // search $this for "staticCallbackIterable"
+        $this->setObject($this);
+
+        $constraint = new Choice(['callback' => 'staticCallbackInvalid']);
+
+        $this->validator->validate('bar', $constraint);
+    }
+
+    public function testValidChoiceCallbackContextMethodIterable()
+    {
+        // search $this for "staticCallbackIterable"
+        $this->setObject($this);
+
+        $constraint = new Choice(['callback' => 'staticCallbackIterable']);
+
+        $this->validator->validate(1, $constraint);
+
+        $this->assertNoViolation();
+    }
+
     public static function provideConstraintsWithMessage(): iterable
     {
         yield 'Doctrine style' => [new Choice(['choices' => ['foo', 'bar'], 'message' => 'myMessage'])];