Issue #3029540 by mikelutz, catch, alexpott, larowlan, Gábor Hojtsy: [Symfony...

use Drupal\Core\Entity\Display\EntityFormDisplayInterface;

use Drupal\Core\Entity\EntityDisplayBase;

use Drupal\Core\Form\FormStateInterface;

use Symfony\Component\Validator\ConstraintViolation;

use Drupal\Core\Validation\ConstraintViolation;

use Symfony\Component\Validator\ConstraintViolationList;

use Symfony\Component\Validator\ConstraintViolationListInterface;

use Drupal\Core\Entity\Plugin\Validation\Constraint\CompositeConstraintBase;

use Drupal\Core\Session\AccountInterface;

use Drupal\Core\StringTranslation\StringTranslationTrait;

use Symfony\Component\Validator\ConstraintViolation;

use Drupal\Core\Validation\ConstraintViolation;

use Symfony\Component\Validator\ConstraintViolationInterface;

use Symfony\Component\Validator\ConstraintViolationList;

namespace Drupal\Core\TypedData\Validation;

use Drupal\Core\Validation\ConstraintViolation;

use Drupal\Core\Validation\TranslatorInterface;

use Symfony\Component\Validator\Constraint;

use Symfony\Component\Validator\ConstraintViolation;

use Symfony\Component\Validator\ConstraintViolationList;

use Symfony\Component\Validator\Util\PropertyPath;

use Symfony\Component\Validator\Violation\ConstraintViolationBuilderInterface;

namespace Drupal\Core\TypedData\Validation;

use Drupal\Core\Validation\ConstraintViolation;

use Drupal\Core\Validation\TranslatorInterface;

use Symfony\Component\Validator\Constraint;

use Symfony\Component\Validator\ConstraintViolation;

use Symfony\Component\Validator\ConstraintViolationList;

use Symfony\Component\Validator\Context\ExecutionContextInterface;

use Symfony\Component\Validator\Mapping\MetadataInterface;

<?php

namespace Drupal\Core\Validation;

use Symfony\Component\Validator\Constraint;

use Symfony\Component\Validator\ConstraintViolation as SymfonyConstraintViolation;

/**

 * ConstraintViolation subclass to handle markup in messages.

 *

 * In symfony 4, the message in a violation is typecast to string.  This class

 * allows for a markup object to be used instead.

 */

class ConstraintViolation extends SymfonyConstraintViolation {

  /**

   * The violation message, may be markup or a string.

   *

   * @var \Drupal\Component\Render\MarkupInterface|string

   */

  private $originalMessage;

  /**

   * Constructs a ConstraintViolation object.

   *

   * @param \Drupal\Component\Render\MarkupInterface|string $message

   *   The violation message.

   * @param string $messageTemplate

   *   The raw violation message.

   * @param array $parameters

   *   The parameters to substitute in the raw violation message.

   * @param mixed $root

   *   The value originally passed to the validator.

   * @param string|null $propertyPath

   *   The property path from the root value to the invalid value.

   * @param mixed $invalidValue

   *   The invalid value that caused this violation.

   * @param int|null $plural

   *   The number for determining the plural form when translating the message.

   * @param mixed $code

   *   The error code of the violation.

   * @param \Symfony\Component\Validator\Constraint|null $constraint

   *   The constraint whose validation caused the violation.

   * @param mixed $cause

   *   The cause of the violation.

   */

  public function __construct($message, $messageTemplate, array $parameters, $root, $propertyPath, $invalidValue, $plural = NULL, $code = NULL, Constraint $constraint = NULL, $cause = NULL) {

    $this->originalMessage = $message;

    parent::__construct($message, $messageTemplate, $parameters, $root, $propertyPath, $invalidValue, $plural, $code, $constraint, $cause);

  }

  /**

   * Returns the violation message.

   *

   * @return \Drupal\Component\Render\MarkupInterface|string

   *   The violation message

   */

  public function getMessage() {

    return $this->originalMessage;

  }

}