src/Composer/DependencyResolver/Rule.php
protected function formatPackagesUnique($pool, array $packages)
    {
        $prepared = array();
        foreach ($packages as $package) {
            if (!is_object($package)) {
                $package = $pool->literalToPackage($package);
            }
            $prepared[$package->getName()]['name'] = $package->getPrettyName();
            $prepared[$package->getName()]['versions'][$package->getVersion()] = $package->getPrettyVersion();
        }
        foreach ($prepared as $name => $package) {
            $prepared[$name] = $package['name'].'['.implode(', ', $package['versions']).']';
        }

        return implode(', ', $prepared);
    }
protected function formatPackagesUnique($pool, array $packages)
    {
        $prepared = array();
        foreach ($packages as $package) {
            if (!is_object($package)) {
                $package = $pool->literalToPackage($package);
            }
            $prepared[$package->getName()]['name'] = $package->getPrettyName();
            $prepared[$package->getName()]['versions'][$package->getVersion()] = $package->getPrettyVersion();
        }
        foreach ($prepared as $name => $package) {
            $prepared[$name] = $package['name'].'['.implode(', ', $package['versions']).']';
        }

        return implode(', ', $prepared);
    }
@param Pool  $pool
@param array $packages

@return string