This file is indexed.

/usr/share/php/Symfony/Component/Validator/Validator/RecursiveContextualValidator.php is in php-symfony-validator 3.4.6+dfsg-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
<?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.
 */

namespace Symfony\Component\Validator\Validator;

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;
use Symfony\Component\Validator\Exception\RuntimeException;
use Symfony\Component\Validator\Exception\UnsupportedMetadataException;
use Symfony\Component\Validator\Exception\ValidatorException;
use Symfony\Component\Validator\Mapping\CascadingStrategy;
use Symfony\Component\Validator\Mapping\ClassMetadataInterface;
use Symfony\Component\Validator\Mapping\GenericMetadata;
use Symfony\Component\Validator\Mapping\MetadataInterface;
use Symfony\Component\Validator\Mapping\PropertyMetadataInterface;
use Symfony\Component\Validator\Mapping\TraversalStrategy;
use Symfony\Component\Validator\Mapping\Factory\MetadataFactoryInterface;
use Symfony\Component\Validator\ObjectInitializerInterface;
use Symfony\Component\Validator\Util\PropertyPath;

/**
 * Recursive implementation of {@link ContextualValidatorInterface}.
 *
 * @author Bernhard Schussek <bschussek@gmail.com>
 */
class RecursiveContextualValidator implements ContextualValidatorInterface
{
    private $context;
    private $defaultPropertyPath;
    private $defaultGroups;
    private $metadataFactory;
    private $validatorFactory;
    private $objectInitializers;

    /**
     * Creates a validator for the given context.
     *
     * @param ExecutionContextInterface           $context            The execution context
     * @param MetadataFactoryInterface            $metadataFactory    The factory for
     *                                                                fetching the metadata
     *                                                                of validated objects
     * @param ConstraintValidatorFactoryInterface $validatorFactory   The factory for creating
     *                                                                constraint validators
     * @param ObjectInitializerInterface[]        $objectInitializers The object initializers
     */
    public function __construct(ExecutionContextInterface $context, MetadataFactoryInterface $metadataFactory, ConstraintValidatorFactoryInterface $validatorFactory, array $objectInitializers = array())
    {
        $this->context = $context;
        $this->defaultPropertyPath = $context->getPropertyPath();
        $this->defaultGroups = array($context->getGroup() ?: Constraint::DEFAULT_GROUP);
        $this->metadataFactory = $metadataFactory;
        $this->validatorFactory = $validatorFactory;
        $this->objectInitializers = $objectInitializers;
    }

    /**
     * {@inheritdoc}
     */
    public function atPath($path)
    {
        $this->defaultPropertyPath = $this->context->getPropertyPath($path);

        return $this;
    }

    /**
     * {@inheritdoc}
     */
    public function validate($value, $constraints = null, $groups = null)
    {
        $groups = $groups ? $this->normalizeGroups($groups) : $this->defaultGroups;

        $previousValue = $this->context->getValue();
        $previousObject = $this->context->getObject();
        $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
        if (null !== $constraints) {
            // You can pass a single constraint or an array of constraints
            // Make sure to deal with an array in the rest of the code
            if (!is_array($constraints)) {
                $constraints = array($constraints);
            }

            $metadata = new GenericMetadata();
            $metadata->addConstraints($constraints);

            $this->validateGenericNode(
                $value,
                $previousObject,
                is_object($value) ? spl_object_hash($value) : null,
                $metadata,
                $this->defaultPropertyPath,
                $groups,
                null,
                TraversalStrategy::IMPLICIT,
                $this->context
            );

            $this->context->setNode($previousValue, $previousObject, $previousMetadata, $previousPath);
            $this->context->setGroup($previousGroup);

            if (null !== $previousConstraint) {
                $this->context->setConstraint($previousConstraint);
            }

            return $this;
        }

        // If an object is passed without explicit constraints, validate that
        // object against the constraints defined for the object's class
        if (is_object($value)) {
            $this->validateObject(
                $value,
                $this->defaultPropertyPath,
                $groups,
                TraversalStrategy::IMPLICIT,
                $this->context
            );

            $this->context->setNode($previousValue, $previousObject, $previousMetadata, $previousPath);
            $this->context->setGroup($previousGroup);

            return $this;
        }

        // If an array is passed without explicit constraints, validate each
        // object in the array
        if (is_array($value)) {
            $this->validateEachObjectIn(
                $value,
                $this->defaultPropertyPath,
                $groups,
                $this->context
            );

            $this->context->setNode($previousValue, $previousObject, $previousMetadata, $previousPath);
            $this->context->setGroup($previousGroup);

            return $this;
        }

        throw new RuntimeException(sprintf(
            'Cannot validate values of type "%s" automatically. Please '.
            'provide a constraint.',
            gettype($value)
        ));
    }

    /**
     * {@inheritdoc}
     */
    public function validateProperty($object, $propertyName, $groups = null)
    {
        $classMetadata = $this->metadataFactory->getMetadataFor($object);

        if (!$classMetadata instanceof ClassMetadataInterface) {
            throw new ValidatorException(sprintf(
                'The metadata factory should return instances of '.
                '"\Symfony\Component\Validator\Mapping\ClassMetadataInterface", '.
                'got: "%s".',
                is_object($classMetadata) ? get_class($classMetadata) : gettype($classMetadata)
            ));
        }

        $propertyMetadatas = $classMetadata->getPropertyMetadata($propertyName);
        $groups = $groups ? $this->normalizeGroups($groups) : $this->defaultGroups;
        $cacheKey = spl_object_hash($object);
        $propertyPath = PropertyPath::append($this->defaultPropertyPath, $propertyName);

        $previousValue = $this->context->getValue();
        $previousObject = $this->context->getObject();
        $previousMetadata = $this->context->getMetadata();
        $previousPath = $this->context->getPropertyPath();
        $previousGroup = $this->context->getGroup();

        foreach ($propertyMetadatas as $propertyMetadata) {
            $propertyValue = $propertyMetadata->getPropertyValue($object);

            $this->validateGenericNode(
                $propertyValue,
                $object,
                $cacheKey.':'.get_class($object).':'.$propertyName,
                $propertyMetadata,
                $propertyPath,
                $groups,
                null,
                TraversalStrategy::IMPLICIT,
                $this->context
            );
        }

        $this->context->setNode($previousValue, $previousObject, $previousMetadata, $previousPath);
        $this->context->setGroup($previousGroup);

        return $this;
    }

    /**
     * {@inheritdoc}
     */
    public function validatePropertyValue($objectOrClass, $propertyName, $value, $groups = null)
    {
        $classMetadata = $this->metadataFactory->getMetadataFor($objectOrClass);

        if (!$classMetadata instanceof ClassMetadataInterface) {
            throw new ValidatorException(sprintf(
                'The metadata factory should return instances of '.
                '"\Symfony\Component\Validator\Mapping\ClassMetadataInterface", '.
                'got: "%s".',
                is_object($classMetadata) ? get_class($classMetadata) : gettype($classMetadata)
            ));
        }

        $propertyMetadatas = $classMetadata->getPropertyMetadata($propertyName);
        $groups = $groups ? $this->normalizeGroups($groups) : $this->defaultGroups;

        if (is_object($objectOrClass)) {
            $object = $objectOrClass;
            $class = get_class($object);
            $cacheKey = spl_object_hash($objectOrClass);
            $propertyPath = PropertyPath::append($this->defaultPropertyPath, $propertyName);
        } else {
            // $objectOrClass contains a class name
            $object = null;
            $class = $objectOrClass;
            $cacheKey = null;
            $propertyPath = $this->defaultPropertyPath;
        }

        $previousValue = $this->context->getValue();
        $previousObject = $this->context->getObject();
        $previousMetadata = $this->context->getMetadata();
        $previousPath = $this->context->getPropertyPath();
        $previousGroup = $this->context->getGroup();

        foreach ($propertyMetadatas as $propertyMetadata) {
            $this->validateGenericNode(
                $value,
                $object,
                $cacheKey.':'.$class.':'.$propertyName,
                $propertyMetadata,
                $propertyPath,
                $groups,
                null,
                TraversalStrategy::IMPLICIT,
                $this->context
            );
        }

        $this->context->setNode($previousValue, $previousObject, $previousMetadata, $previousPath);
        $this->context->setGroup($previousGroup);

        return $this;
    }

    /**
     * {@inheritdoc}
     */
    public function getViolations()
    {
        return $this->context->getViolations();
    }

    /**
     * Normalizes the given group or list of groups to an array.
     *
     * @param mixed $groups The groups to normalize
     *
     * @return array A group array
     */
    protected function normalizeGroups($groups)
    {
        if (is_array($groups)) {
            return $groups;
        }

        return array($groups);
    }

    /**
     * Validates an object against the constraints defined for its class.
     *
     * If no metadata is available for the class, but the class is an instance
     * of {@link \Traversable} and the selected traversal strategy allows
     * traversal, the object will be iterated and each nested object will be
     * validated instead.
     *
     * @param object                    $object            The object to cascade
     * @param string                    $propertyPath      The current property path
     * @param string[]                  $groups            The validated groups
     * @param int                       $traversalStrategy The strategy for traversing the
     *                                                     cascaded object
     * @param ExecutionContextInterface $context           The current execution context
     *
     * @throws NoSuchMetadataException      If the object has no associated metadata
     *                                      and does not implement {@link \Traversable}
     *                                      or if traversal is disabled via the
     *                                      $traversalStrategy argument
     * @throws UnsupportedMetadataException If the metadata returned by the
     *                                      metadata factory does not implement
     *                                      {@link ClassMetadataInterface}
     */
    private function validateObject($object, $propertyPath, array $groups, $traversalStrategy, ExecutionContextInterface $context)
    {
        try {
            $classMetadata = $this->metadataFactory->getMetadataFor($object);

            if (!$classMetadata instanceof ClassMetadataInterface) {
                throw new UnsupportedMetadataException(sprintf(
                    'The metadata factory should return instances of '.
                    '"Symfony\Component\Validator\Mapping\ClassMetadataInterface", '.
                    'got: "%s".',
                    is_object($classMetadata) ? get_class($classMetadata) : gettype($classMetadata)
                ));
            }

            $this->validateClassNode(
                $object,
                spl_object_hash($object),
                $classMetadata,
                $propertyPath,
                $groups,
                null,
                $traversalStrategy,
                $context
            );
        } catch (NoSuchMetadataException $e) {
            // Rethrow if not Traversable
            if (!$object instanceof \Traversable) {
                throw $e;
            }

            // Rethrow unless IMPLICIT or TRAVERSE
            if (!($traversalStrategy & (TraversalStrategy::IMPLICIT | TraversalStrategy::TRAVERSE))) {
                throw $e;
            }

            $this->validateEachObjectIn(
                $object,
                $propertyPath,
                $groups,
                $context
            );
        }
    }

    /**
     * Validates each object in a collection against the constraints defined
     * for their classes.
     *
     * If the parameter $recursive is set to true, nested {@link \Traversable}
     * objects are iterated as well. Nested arrays are always iterated,
     * regardless of the value of $recursive.
     *
     * @param iterable                  $collection   The collection
     * @param string                    $propertyPath The current property path
     * @param string[]                  $groups       The validated groups
     * @param ExecutionContextInterface $context      The current execution context
     *
     * @see ClassNode
     * @see CollectionNode
     */
    private function validateEachObjectIn($collection, $propertyPath, array $groups, ExecutionContextInterface $context)
    {
        foreach ($collection as $key => $value) {
            if (is_array($value)) {
                // Arrays are always cascaded, independent of the specified
                // traversal strategy
                $this->validateEachObjectIn(
                    $value,
                    $propertyPath.'['.$key.']',
                    $groups,
                    $context
                );

                continue;
            }

            // Scalar and null values in the collection are ignored
            if (is_object($value)) {
                $this->validateObject(
                    $value,
                    $propertyPath.'['.$key.']',
                    $groups,
                    TraversalStrategy::IMPLICIT,
                    $context
                );
            }
        }
    }

    /**
     * Validates a class node.
     *
     * A class node is a combination of an object with a {@link ClassMetadataInterface}
     * instance. Each class node (conceptionally) has zero or more succeeding
     * property nodes:
     *
     *     (Article:class node)
     *                \
     *        ($title:property node)
     *
     * This method validates the passed objects against all constraints defined
     * at class level. It furthermore triggers the validation of each of the
     * class' properties against the constraints for that property.
     *
     * If the selected traversal strategy allows traversal, the object is
     * iterated and each nested object is validated against its own constraints.
     * The object is not traversed if traversal is disabled in the class
     * metadata.
     *
     * If the passed groups contain the group "Default", the validator will
     * check whether the "Default" group has been replaced by a group sequence
     * in the class metadata. If this is the case, the group sequence is
     * validated instead.
     *
     * @param object                    $object            The validated object
     * @param string                    $cacheKey          The key for caching
     *                                                     the validated object
     * @param ClassMetadataInterface    $metadata          The class metadata of
     *                                                     the object
     * @param string                    $propertyPath      The property path leading
     *                                                     to the object
     * @param string[]                  $groups            The groups in which the
     *                                                     object should be validated
     * @param string[]|null             $cascadedGroups    The groups in which
     *                                                     cascaded objects should
     *                                                     be validated
     * @param int                       $traversalStrategy The strategy used for
     *                                                     traversing the object
     * @param ExecutionContextInterface $context           The current execution context
     *
     * @throws UnsupportedMetadataException  If a property metadata does not
     *                                       implement {@link PropertyMetadataInterface}
     * @throws ConstraintDefinitionException If traversal was enabled but the
     *                                       object does not implement
     *                                       {@link \Traversable}
     *
     * @see TraversalStrategy
     */
    private function validateClassNode($object, $cacheKey, ClassMetadataInterface $metadata = null, $propertyPath, array $groups, $cascadedGroups, $traversalStrategy, ExecutionContextInterface $context)
    {
        $context->setNode($object, $object, $metadata, $propertyPath);

        if (!$context->isObjectInitialized($cacheKey)) {
            foreach ($this->objectInitializers as $initializer) {
                $initializer->initialize($object);
            }

            $context->markObjectAsInitialized($cacheKey);
        }

        foreach ($groups as $key => $group) {
            // If the "Default" group is replaced by a group sequence, remember
            // to cascade the "Default" group when traversing the group
            // sequence
            $defaultOverridden = false;

            // Use the object hash for group sequences
            $groupHash = is_object($group) ? spl_object_hash($group) : $group;

            if ($context->isGroupValidated($cacheKey, $groupHash)) {
                // Skip this group when validating the properties and when
                // traversing the object
                unset($groups[$key]);

                continue;
            }

            $context->markGroupAsValidated($cacheKey, $groupHash);

            // Replace the "Default" group by the group sequence defined
            // for the class, if applicable.
            // This is done after checking the cache, so that
            // spl_object_hash() isn't called for this sequence and
            // "Default" is used instead in the cache. This is useful
            // if the getters below return different group sequences in
            // every call.
            if (Constraint::DEFAULT_GROUP === $group) {
                if ($metadata->hasGroupSequence()) {
                    // The group sequence is statically defined for the class
                    $group = $metadata->getGroupSequence();
                    $defaultOverridden = true;
                } elseif ($metadata->isGroupSequenceProvider()) {
                    // The group sequence is dynamically obtained from the validated
                    // object
                    /* @var \Symfony\Component\Validator\GroupSequenceProviderInterface $object */
                    $group = $object->getGroupSequence();
                    $defaultOverridden = true;

                    if (!$group instanceof GroupSequence) {
                        $group = new GroupSequence($group);
                    }
                }
            }

            // If the groups (=[<G1,G2>,G3,G4]) contain a group sequence
            // (=<G1,G2>), then call validateClassNode() with each entry of the
            // group sequence and abort if necessary (G1, G2)
            if ($group instanceof GroupSequence) {
                $this->stepThroughGroupSequence(
                     $object,
                     $object,
                     $cacheKey,
                     $metadata,
                     $propertyPath,
                     $traversalStrategy,
                     $group,
                     $defaultOverridden ? Constraint::DEFAULT_GROUP : null,
                     $context
                );

                // Skip the group sequence when validating properties, because
                // stepThroughGroupSequence() already validates the properties
                unset($groups[$key]);

                continue;
            }

            $this->validateInGroup($object, $cacheKey, $metadata, $group, $context);
        }

        // If no more groups should be validated for the property nodes,
        // we can safely quit
        if (0 === count($groups)) {
            return;
        }

        // Validate all properties against their constraints
        foreach ($metadata->getConstrainedProperties() as $propertyName) {
            // If constraints are defined both on the getter of a property as
            // well as on the property itself, then getPropertyMetadata()
            // returns two metadata objects, not just one
            foreach ($metadata->getPropertyMetadata($propertyName) as $propertyMetadata) {
                if (!$propertyMetadata instanceof PropertyMetadataInterface) {
                    throw new UnsupportedMetadataException(sprintf(
                        'The property metadata instances should implement '.
                        '"Symfony\Component\Validator\Mapping\PropertyMetadataInterface", '.
                        'got: "%s".',
                        is_object($propertyMetadata) ? get_class($propertyMetadata) : gettype($propertyMetadata)
                    ));
                }

                $propertyValue = $propertyMetadata->getPropertyValue($object);

                $this->validateGenericNode(
                    $propertyValue,
                    $object,
                    $cacheKey.':'.get_class($object).':'.$propertyName,
                    $propertyMetadata,
                    PropertyPath::append($propertyPath, $propertyName),
                    $groups,
                    $cascadedGroups,
                    TraversalStrategy::IMPLICIT,
                    $context
                );
            }
        }

        // If no specific traversal strategy was requested when this method
        // was called, use the traversal strategy of the class' metadata
        if ($traversalStrategy & TraversalStrategy::IMPLICIT) {
            $traversalStrategy = $metadata->getTraversalStrategy();
        }

        // Traverse only if IMPLICIT or TRAVERSE
        if (!($traversalStrategy & (TraversalStrategy::IMPLICIT | TraversalStrategy::TRAVERSE))) {
            return;
        }

        // If IMPLICIT, stop unless we deal with a Traversable
        if ($traversalStrategy & TraversalStrategy::IMPLICIT && !$object instanceof \Traversable) {
            return;
        }

        // If TRAVERSE, fail if we have no Traversable
        if (!$object instanceof \Traversable) {
            throw new ConstraintDefinitionException(sprintf(
                'Traversal was enabled for "%s", but this class '.
                'does not implement "\Traversable".',
                get_class($object)
            ));
        }

        $this->validateEachObjectIn(
            $object,
            $propertyPath,
            $groups,
            $context
        );
    }

    /**
     * Validates a node that is not a class node.
     *
     * Currently, two such node types exist:
     *
     *  - property nodes, which consist of the value of an object's
     *    property together with a {@link PropertyMetadataInterface} instance
     *  - generic nodes, which consist of a value and some arbitrary
     *    constraints defined in a {@link MetadataInterface} container
     *
     * In both cases, the value is validated against all constraints defined
     * in the passed metadata object. Then, if the value is an instance of
     * {@link \Traversable} and the selected traversal strategy permits it,
     * the value is traversed and each nested object validated against its own
     * constraints. Arrays are always traversed.
     *
     * @param mixed                     $value             The validated value
     * @param object|null               $object            The current object
     * @param string                    $cacheKey          The key for caching
     *                                                     the validated value
     * @param MetadataInterface         $metadata          The metadata of the
     *                                                     value
     * @param string                    $propertyPath      The property path leading
     *                                                     to the value
     * @param string[]                  $groups            The groups in which the
     *                                                     value should be validated
     * @param string[]|null             $cascadedGroups    The groups in which
     *                                                     cascaded objects should
     *                                                     be validated
     * @param int                       $traversalStrategy The strategy used for
     *                                                     traversing the value
     * @param ExecutionContextInterface $context           The current execution context
     *
     * @see TraversalStrategy
     */
    private function validateGenericNode($value, $object, $cacheKey, MetadataInterface $metadata = null, $propertyPath, array $groups, $cascadedGroups, $traversalStrategy, ExecutionContextInterface $context)
    {
        $context->setNode($value, $object, $metadata, $propertyPath);

        foreach ($groups as $key => $group) {
            if ($group instanceof GroupSequence) {
                $this->stepThroughGroupSequence(
                     $value,
                     $object,
                     $cacheKey,
                     $metadata,
                     $propertyPath,
                     $traversalStrategy,
                     $group,
                     null,
                     $context
                );

                // Skip the group sequence when cascading, as the cascading
                // logic is already done in stepThroughGroupSequence()
                unset($groups[$key]);

                continue;
            }

            $this->validateInGroup($value, $cacheKey, $metadata, $group, $context);
        }

        if (0 === count($groups)) {
            return;
        }

        if (null === $value) {
            return;
        }

        $cascadingStrategy = $metadata->getCascadingStrategy();

        // Quit unless we have an array or a cascaded object
        if (!is_array($value) && !($cascadingStrategy & CascadingStrategy::CASCADE)) {
            return;
        }

        // If no specific traversal strategy was requested when this method
        // was called, use the traversal strategy of the node's metadata
        if ($traversalStrategy & TraversalStrategy::IMPLICIT) {
            $traversalStrategy = $metadata->getTraversalStrategy();
        }

        // The $cascadedGroups property is set, if the "Default" group is
        // overridden by a group sequence
        // See validateClassNode()
        $cascadedGroups = null !== $cascadedGroups && count($cascadedGroups) > 0 ? $cascadedGroups : $groups;

        if (is_array($value)) {
            // Arrays are always traversed, independent of the specified
            // traversal strategy
            $this->validateEachObjectIn(
                $value,
                $propertyPath,
                $cascadedGroups,
                $context
            );

            return;
        }

        // If the value is a scalar, pass it anyway, because we want
        // a NoSuchMetadataException to be thrown in that case
        $this->validateObject(
            $value,
            $propertyPath,
            $cascadedGroups,
            $traversalStrategy,
            $context
        );

        // Currently, the traversal strategy can only be TRAVERSE for a
        // generic node if the cascading strategy is CASCADE. Thus, traversable
        // objects will always be handled within validateObject() and there's
        // nothing more to do here.

        // see GenericMetadata::addConstraint()
    }

    /**
     * Sequentially validates a node's value in each group of a group sequence.
     *
     * If any of the constraints generates a violation, subsequent groups in the
     * group sequence are skipped.
     *
     * @param mixed                     $value             The validated value
     * @param object|null               $object            The current object
     * @param string                    $cacheKey          The key for caching
     *                                                     the validated value
     * @param MetadataInterface         $metadata          The metadata of the
     *                                                     value
     * @param string                    $propertyPath      The property path leading
     *                                                     to the value
     * @param int                       $traversalStrategy The strategy used for
     *                                                     traversing the value
     * @param GroupSequence             $groupSequence     The group sequence
     * @param string|null               $cascadedGroup     The group that should
     *                                                     be passed to cascaded
     *                                                     objects instead of
     *                                                     the group sequence
     * @param ExecutionContextInterface $context           The execution context
     */
    private function stepThroughGroupSequence($value, $object, $cacheKey, MetadataInterface $metadata = null, $propertyPath, $traversalStrategy, GroupSequence $groupSequence, $cascadedGroup, ExecutionContextInterface $context)
    {
        $violationCount = count($context->getViolations());
        $cascadedGroups = $cascadedGroup ? array($cascadedGroup) : null;

        foreach ($groupSequence->groups as $groupInSequence) {
            $groups = (array) $groupInSequence;

            if ($metadata instanceof ClassMetadataInterface) {
                $this->validateClassNode(
                     $value,
                     $cacheKey,
                     $metadata,
                     $propertyPath,
                     $groups,
                     $cascadedGroups,
                     $traversalStrategy,
                     $context
                );
            } else {
                $this->validateGenericNode(
                     $value,
                     $object,
                     $cacheKey,
                     $metadata,
                     $propertyPath,
                     $groups,
                     $cascadedGroups,
                     $traversalStrategy,
                     $context
                );
            }

            // Abort sequence validation if a violation was generated
            if (count($context->getViolations()) > $violationCount) {
                break;
            }
        }
    }

    /**
     * Validates a node's value against all constraints in the given group.
     *
     * @param mixed                     $value    The validated value
     * @param string                    $cacheKey The key for caching the
     *                                            validated value
     * @param MetadataInterface         $metadata The metadata of the value
     * @param string                    $group    The group to validate
     * @param ExecutionContextInterface $context  The execution context
     */
    private function validateInGroup($value, $cacheKey, MetadataInterface $metadata, $group, ExecutionContextInterface $context)
    {
        $context->setGroup($group);

        foreach ($metadata->findConstraints($group) as $constraint) {
            // Prevent duplicate validation of constraints, in the case
            // that constraints belong to multiple validated groups
            if (null !== $cacheKey) {
                $constraintHash = spl_object_hash($constraint);

                if ($context->isConstraintValidated($cacheKey, $constraintHash)) {
                    continue;
                }

                $context->markConstraintAsValidated($cacheKey, $constraintHash);
            }

            $context->setConstraint($constraint);

            $validator = $this->validatorFactory->getInstance($constraint);
            $validator->initialize($context);
            $validator->validate($value, $constraint);
        }
    }
}