<?php
/**
 * PHPUnit
 *
 * Copyright (c) 2002-2008, Sebastian Bergmann <sb@sebastian-bergmann.de>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *
 *   * Neither the name of Sebastian Bergmann nor the names of his
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @category   Testing
 * @package    PHPUnit
 * @author     Jan Borsodi <jb@ez.no>
 * @author     Sebastian Bergmann <sb@sebastian-bergmann.de>
 * @copyright  2002-2008 Sebastian Bergmann <sb@sebastian-bergmann.de>
 * @license    http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @version    SVN: $Id: Xor.php 3164 2008-06-08 12:22:29Z sb $
 * @link       http://www.phpunit.de/
 * @since      File available since Release 3.0.0
 */

require_once 'PHPUnit/Framework.php';
require_once 'PHPUnit/Util/Filter.php';
require_once 'PHPUnit/Util/Type.php';

PHPUnit_Util_Filter::addFileToFilter(__FILE__, 'PHPUNIT');

/**
 * Logical XOR.
 *
 * @category   Testing
 * @package    PHPUnit
 * @author     Sebastian Bergmann <sb@sebastian-bergmann.de>
 * @copyright  2002-2008 Sebastian Bergmann <sb@sebastian-bergmann.de>
 * @license    http://www.opensource.org/licenses/bsd-license.php  BSD License
 * @version    Release: 3.3.1
 * @link       http://www.phpunit.de/
 * @since      Class available since Release 3.0.0
 */
class PHPUnit_Framework_Constraint_Xor extends PHPUnit_Framework_Constraint
{
    protected $constraints = array();

    public function setConstraints(array $constraints)
    {
        $this->constraints = array();

        foreach($constraints as $key => $constraint) {
            if (!($constraint instanceof PHPUnit_Framework_Constraint)) {
                $constraint = new PHPUnit_Framework_Constraint_IsEqual($constraint);
            }

            $this->constraints[] = $constraint;
        }
    }

    /**
     * Evaluates the constraint for parameter $other. Returns TRUE if the
     * constraint is met, FALSE otherwise.
     *
     * @param mixed $other Value or object to evaluate.
     * @return bool
     */
    public function evaluate($other)
    {
        $result = FALSE;

        foreach($this->constraints as $constraint) {
            if ($constraint->evaluate($other)) {
                if ( $result )
                {
                    return FALSE;
                }

                $result = TRUE;
            }
        }

        return $result;
    }

    /**
     * @param   mixed   $other The value passed to evaluate() which failed the
     *                         constraint check.
     * @param   string  $description A string with extra description of what was
     *                               going on while the evaluation failed.
     * @param   boolean $not Flag to indicate negation.
     * @throws  PHPUnit_Framework_ExpectationFailedException
     */
    public function fail($other, $description, $not = FALSE)
    {
        throw new PHPUnit_Framework_ExpectationFailedException(
          sprintf(
            'Failed asserting that %s.',

             $this->toString(),
             NULL,
             $description
          )
        );
    }

    /**
     * Returns a string representation of the constraint.
     *
     * @return string
     */
    public function toString()
    {
        $text = '';

        foreach($this->constraints as $key => $constraint) {
            if ($key > 0) {
                $text .= ' xor ';
            }

            $text .= $constraint->toString();
        }

        return $text;
    }
}
