composer/src/Composer/DependencyResolver/DebugSolver.php

<?php

/*
 * This file is part of Composer.
 *
 * (c) Nils Adermann <naderman@naderman.de>
 *     Jordi Boggiano <j.boggiano@seld.be>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Composer\DependencyResolver;

/**
 * @author Nils Adermann <naderman@naderman.de>
 */
class DebugSolver extends Solver
{
    protected function printDecisionMap()
    {
        echo "\nDecisionMap: \n";
        foreach ($this->decisionMap as $packageId => $level) {
            if ($packageId === 0) {
                continue;
            }
            if ($level > 0) {
                echo '    +' . $this->pool->packageById($packageId)."\n";
            } elseif ($level < 0) {
                echo '    -' . $this->pool->packageById($packageId)."\n";
            } else {
                echo '    ?' . $this->pool->packageById($packageId)."\n";
            }
        }
        echo "\n";
    }

    protected function printDecisionQueue()
    {
        echo "DecisionQueue: \n";
        foreach ($this->decisionQueue as $i => $literal) {
            echo '    ' . $this->pool->literalToString($literal) . ' ' . $this->decisionQueueWhy[$i]." level ".$this->decisionMap[abs($literal)]."\n";
        }
        echo "\n";
    }

    protected function printWatches()
    {
        echo "\nWatches:\n";
        foreach ($this->watches as $literalId => $watch) {
            echo '  '.$this->literalFromId($literalId)."\n";
            $queue = array(array('    ', $watch));

            while (!empty($queue)) {
                list($indent, $watch) = array_pop($queue);

                echo $indent.$watch;

                if ($watch) {
                    echo ' [id='.$watch->getId().',watch1='.$this->literalFromId($watch->watch1).',watch2='.$this->literalFromId($watch->watch2)."]";
                }

                echo "\n";

                if ($watch && ($watch->next1 == $watch || $watch->next2 == $watch)) {
                    if ($watch->next1 == $watch) {
                        echo $indent."    1 *RECURSION*";
                    }
                    if ($watch->next2 == $watch) {
                        echo $indent."    2 *RECURSION*";
                    }
                } elseif ($watch && ($watch->next1 || $watch->next2)) {
                    $indent = str_replace(array('1', '2'), ' ', $indent);

                    array_push($queue, array($indent.'    2 ', $watch->next2));
                    array_push($queue, array($indent.'    1 ', $watch->next1));
                }
            }

            echo "\n";
        }
    }
}