bug symfony#20664 [Validator] ensure the proper context for nested validations (xabbuh)

This PR was merged into the 2.7 branch.

Discussion
----------

[Validator] ensure the proper context for nested validations

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#14639, symfony#20368
| License       | MIT
| Doc PR        | n/a

Commits
-------

56c8ff8 ensure the proper context for nested validations

Author: fabpot

src/Symfony/Component/Validator/Context/ExecutionContext.php

@@ -287,6 +287,11 @@ public function getGroup()
         return $this->group;
     }
 
+    public function getConstraint()
+    {
+        return $this->constraint;
+    }
+
     /**
      * {@inheritdoc}
      */

src/Symfony/Component/Validator/Tests/Validator/Abstract2Dot5ApiTest.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\Validator\Tests\Validator;
 
 use Symfony\Component\Validator\Constraints\Callback;
+use Symfony\Component\Validator\Constraints\Collection;
 use Symfony\Component\Validator\Constraints\GroupSequence;
 use Symfony\Component\Validator\Constraints\NotNull;
 use Symfony\Component\Validator\Constraints\Traverse;
@@ -720,4 +721,22 @@ public function testPassConstraintToViolation()
         $this->assertCount(1, $violations);
         $this->assertSame($constraint, $violations[0]->getConstraint());
     }
+
+    public function testCollectionConstraitViolationHasCorrectContext()
+    {
+        $data = array(
+            'foo' => 'fooValue',
+        );
+
+        // Missing field must not be the first in the collection validation
+        $constraint = new Collection(array(
+            'foo' => new NotNull(),
+            'bar' => new NotNull(),
+        ));
+
+        $violations = $this->validate($data, $constraint);
+
+        $this->assertCount(1, $violations);
+        $this->assertSame($constraint, $violations[0]->getConstraint());
+    }
 }

src/Symfony/Component/Validator/Validator/RecursiveContextualValidator.php

@@ -14,6 +14,7 @@
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\Constraints\GroupSequence;
 use Symfony\Component\Validator\ConstraintValidatorFactoryInterface;
+use Symfony\Component\Validator\Context\ExecutionContext;
 use Symfony\Component\Validator\Context\ExecutionContextInterface;
 use Symfony\Component\Validator\Exception\ConstraintDefinitionException;
 use Symfony\Component\Validator\Exception\NoSuchMetadataException;
@@ -110,6 +111,11 @@ public function validate($value, $constraints = null, $groups = null)
         $previousMetadata = $this->context->getMetadata();
         $previousPath = $this->context->getPropertyPath();
         $previousGroup = $this->context->getGroup();
+        $previousConstraint = null;
+
+        if ($this->context instanceof ExecutionContext || method_exists($this->context, 'getConstraint')) {
+            $previousConstraint = $this->context->getConstraint();
+        }
 
         // If explicit constraints are passed, validate the value against
         // those constraints
@@ -138,6 +144,10 @@ public function validate($value, $constraints = null, $groups = null)
             $this->context->setNode($previousValue, $previousObject, $previousMetadata, $previousPath);
             $this->context->setGroup($previousGroup);
 
+            if (null !== $previousConstraint) {
+                $this->context->setConstraint($previousConstraint);
+            }
+
             return $this;
         }