Merge branch '5.1'

* 5.1:
  [ErrorHandler] fix throwing from __toString()
  Removed comments and requirements relative to php <5.5 (not supported anymore)
  Fix caching of parent locales file in translator
  fix validating lazy properties that evaluate to null

Author: nicolas-grekas

Tests/Fixtures/EntityParent.php

@@ -18,6 +18,7 @@ class EntityParent implements EntityInterfaceA
     protected $firstName;
     private $internal;
     private $data = 'Data';
+    private $child;
 
     /**
      * @NotNull
@@ -28,4 +29,9 @@ public function getData()
     {
         return 'Data';
     }
+
+    public function getChild()
+    {
+        return $this->child;
+    }
 }

Tests/Validator/RecursiveValidatorTest.php

@@ -21,13 +21,15 @@
 use Symfony\Component\Validator\Constraints\NotNull;
 use Symfony\Component\Validator\Constraints\Optional;
 use Symfony\Component\Validator\Constraints\Required;
+use Symfony\Component\Validator\Constraints\Valid;
 use Symfony\Component\Validator\ConstraintValidatorFactory;
 use Symfony\Component\Validator\Context\ExecutionContextFactory;
 use Symfony\Component\Validator\Mapping\ClassMetadata;
 use Symfony\Component\Validator\Mapping\Factory\MetadataFactoryInterface;
 use Symfony\Component\Validator\Tests\Constraints\Fixtures\ChildA;
 use Symfony\Component\Validator\Tests\Constraints\Fixtures\ChildB;
 use Symfony\Component\Validator\Tests\Fixtures\Entity;
+use Symfony\Component\Validator\Tests\Fixtures\EntityParent;
 use Symfony\Component\Validator\Tests\Fixtures\EntityWithGroupedConstraintOnMethods;
 use Symfony\Component\Validator\Validator\RecursiveValidator;
 use Symfony\Component\Validator\Validator\ValidatorInterface;
@@ -144,6 +146,31 @@ public function testGroupedMethodConstraintValidateInSequence()
         $this->assertInstanceOf(IsTrue::class, $violations->get(1)->getConstraint());
     }
 
+    public function testValidConstraintOnGetterReturningNull()
+    {
+        $metadata = new ClassMetadata(EntityParent::class);
+        $metadata->addGetterConstraint('child', new Valid());
+
+        $this->metadataFactory->addMetadata($metadata);
+
+        $violations = $this->validator->validate(new EntityParent());
+
+        $this->assertCount(0, $violations);
+    }
+
+    public function testNotNullConstraintOnGetterReturningNull()
+    {
+        $metadata = new ClassMetadata(EntityParent::class);
+        $metadata->addGetterConstraint('child', new NotNull());
+
+        $this->metadataFactory->addMetadata($metadata);
+
+        $violations = $this->validator->validate(new EntityParent());
+
+        $this->assertCount(1, $violations);
+        $this->assertInstanceOf(NotNull::class, $violations->get(0)->getConstraint());
+    }
+
     public function testAllConstraintValidateAllGroupsForNestedConstraints()
     {
         $this->metadata->addPropertyConstraint('data', new All(['constraints' => [

Validator/RecursiveContextualValidator.php

@@ -630,6 +630,10 @@ private function validateGenericNode($value, ?object $object, ?string $cacheKey,
 
         if ($value instanceof LazyProperty) {
             $value = $value->getPropertyValue();
+
+            if (null === $value) {
+                return;
+            }
         }
 
         if (\is_array($value)) {