symfony/src/Symfony/Components/Console/Helper/DialogHelper.php

<?php

namespace Symfony\Components\Console\Helper;

use Symfony\Components\Console\Output\OutputInterface;

/*
 * This file is part of the Symfony framework.
 *
 * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */

/**
 * The Dialog class provides helpers to interact with the user.
 *
 * @package    Symfony
 * @subpackage Components_Console
 * @author     Fabien Potencier <fabien.potencier@symfony-project.com>
 */
class DialogHelper extends Helper
{
    /**
     * Asks a question to the user.
     *
     * @param OutputInterface $output
     * @param string|array    $question The question to ask
     * @param string          $default  The default answer if none is given by the user
     *
     * @param string The user answer
     */
    public function ask(OutputInterface $output, $question, $default = null)
    {
        // @codeCoverageIgnoreStart
        $output->writeln($question);

        $ret = trim(fgets(STDIN));

        return $ret ? $ret : $default;
        // @codeCoverageIgnoreEnd
    }

    /**
     * Asks a confirmation to the user.
     *
     * The question will be asked until the user answer by nothing, yes, or no.
     *
     * @param OutputInterface $output
     * @param string|array    $question The question to ask
     * @param Boolean         $default  The default answer if the user enters nothing
     *
     * @param Boolean true if the user has confirmed, false otherwise
     */
    public function askConfirmation(OutputInterface $output, $question, $default = true)
    {
        // @codeCoverageIgnoreStart
        $answer = 'z';
        while ($answer && !in_array(strtolower($answer[0]), array('y', 'n'))) {
            $answer = $this->ask($output, $question);
        }

        if (false === $default) {
            return $answer && 'y' == strtolower($answer[0]);
        } else {
            return !$answer || 'y' == strtolower($answer[0]);
        }
        // @codeCoverageIgnoreEnd
    }

    /**
     * Asks for a value and validates the response.
     *
     * @param OutputInterface $output
     * @param string|array    $question
     * @param Closure         $validator
     * @param integer         $attempts Max number of times to ask before giving up (false by default, which means infinite)
     *
     * @return mixed
     *
     * @throws \Exception When any of the validator returns an error
     */
    public function askAndValidate(OutputInterface $output, $question, \Closure $validator, $attempts = false)
    {
        // @codeCoverageIgnoreStart
        $error = null;
        while (false === $attempts || $attempts--) {
            if (null !== $error) {
                $output->writeln($this->getHelperSet()->get('formatter')->formatBlock($error->getMessage(), 'error'));
            }

            $value = $this->ask($output, $question, null);

            try {
                return $validator($value);
            } catch (\Exception $error) {
            }
        }

        throw $error;
        // @codeCoverageIgnoreEnd
    }

    /**
     * Returns the helper's canonical name
     */
    public function getName()
    {
        return 'dialog';
    }
}