Fleshgrinder/php-constraint-violations

<?php
/**
 * @author Richard Fussenegger <fleshgrinder@users.noreply.github.com>
 * @copyright 2016 Richard Fussenegger
 * @license MIT
 */

namespace Fleshgrinder\Constraints;

use Countable;
use Exception;
use Generator;
use IteratorAggregate;
use UnexpectedValueException;

/**
 * The constraint violation collector can be used to collect messages and their possible causes during validation. This
 * class may be extended to provide additional functionality or simply to construct different objects in the
 * {@see Violations::addMessage()} method.
 *
 * Note that this class does not clone the violation instances that are added to it. The generic {@see Violation}
 * implementation is immutable and extending classes should be too.
 */
class ViolationCollector implements Countable, IteratorAggregate {

    /** @var Violation[] */
    private $violations = [];

    /**
     * Add a child instance of {@see Violation} to the collector. This method should not be used to add {@see Violation}
     * instances to the collector use {@see ViolationCollector::addViolation()} instead. The using code is cleaner
     * without any `new Violation` code.
     *
     * @see ViolationCollector::addViolation()
     * @param $violation
     */
    public function add(Violation $violation) {
        $this->violations[] = $violation;
    }

    /**
     * Add a {@see Violation} to the collector.
     *
     * @param $message
     *     that explains the violation in user language.
     * @param $cause
     *     that lead to the violation and explains it in developer language.
     */
    public function addViolation(string $message, Exception $cause = null) {
        $this->violations[] = new Violation($message, $cause);
    }

    /** @inheritDoc */
    public function count() {
        return count($this->violations);
    }

    /**
     * Get all collected constraint violation causes, if any.
     *
     * @return Generator|Exception[]
     */
    public function getCauses(): Generator {
        foreach ($this->violations as $violation) {
            $cause = $violation->getCause();
            if (isset($cause)) {
                yield $cause;
            }
        }
    }

    /** @inheritDoc */
    public function getIterator() {
        foreach ($this->violations as $violation) {
            yield $violation;
        }
    }

    /**
     * Get all collected constraint violation messages, if any.
     *
     * @return Generator|string[]
     */
    public function getMessages(): Generator {
        foreach ($this->violations as $violation) {
            yield $violation->getMessage();
        }
    }

    /**
     * Check if any constraint violations were collected.
     */
    public function hasViolations(): bool {
        return !empty($this->violations);
    }

    //@formatter:off
    //@codeCoverageIgnoreStart
    //@codingStandardsIgnoreStart
    private function __clone(){}
    private function __sleep(){}
    private function __wakeup(){}
    //@codingStandardsIgnoreEnd
    //@codeCoverageIgnoreEnd
    //@formatter:on

}