title: Directory name must not be empty
body: <p>I got the below error when i tried to run <code>composer update</code>
  I tried to do <code>composer clear</code> and that didn't help. Works on my local windows machine but doesnt work i deploy it to a centos machine. I'n not running laravel, just composer.</p>
  
  <p>My composer.json file:</p>
  
  <pre><code>{
    "autoload": {
      "psr-4": {
        "App\\": "/",
        "App\\includes\\": "/includes/"
  
      },"classmap": [
        "/",
        "includes/"
      ]
    },
    "require": {
      "gebn/brush": "^1.1",
      "rap2hpoutre/similar-text-finder": "^1.0",
      "sendgrid/sendgrid": "^7.2"
    }
  }
  </code></pre>
  
  <p>Error log via -v</p>
  
  <pre><code>Exception trace:
   () at phar:///usr/local/bin/composer/vendor/symfony/finder/Iterator/RecursiveDirectoryIterator.php:52
   RecursiveDirectoryIterator-&gt;__construct() at phar:///usr/local/bin/composer/vendor/symfony/finder/Iterator/RecursiveDirectoryIterator.php:52
   Symfony\Component\Finder\Iterator\RecursiveDirectoryIterator-&gt;__construct() at phar:///usr/local/bin/composer/vendor/symfony/finder/Finder.php:809
   Symfony\Component\Finder\Finder-&gt;searchInDirectory() at phar:///usr/local/bin/composer/vendor/symfony/finder/Finder.php:682
   Symfony\Component\Finder\Finder-&gt;getIterator() at phar:///usr/local/bin/composer/src/Composer/Autoload/ClassMapGenerator.php:80
   Composer\Autoload\ClassMapGenerator::createMap() at phar:///usr/local/bin/composer/src/Composer/Autoload/AutoloadGenerator.php:336
   Composer\Autoload\AutoloadGenerator-&gt;generateClassMap() at phar:///usr/local/bin/composer/src/Composer/Autoload/AutoloadGenerator.php:319
   Composer\Autoload\AutoloadGenerator-&gt;addClassMapCode() at phar:///usr/local/bin/composer/src/Composer/Autoload/AutoloadGenerator.php:266
   Composer\Autoload\AutoloadGenerator-&gt;dump() at phar:///usr/local/bin/composer/src/Composer/Installer.php:303
   Composer\Installer-&gt;run() at phar:///usr/local/bin/composer/src/Composer/Command/UpdateCommand.php:162
   Composer\Command\UpdateCommand-&gt;execute() at phar:///usr/local/bin/composer/vendor/symfony/console/Command/Command.php:241
   Symfony\Component\Console\Command\Command-&gt;run() at phar:///usr/local/bin/composer/vendor/symfony/console/Application.php:843
   Symfony\Component\Console\Application-&gt;doRunCommand() at phar:///usr/local/bin/composer/vendor/symfony/console/Application.php:193
   Symfony\Component\Console\Application-&gt;doRun() at phar:///usr/local/bin/composer/src/Composer/Console/Application.php:254
   Composer\Console\Application-&gt;doRun() at phar:///usr/local/bin/composer/vendor/symfony/console/Application.php:117
   Symfony\Component\Console\Application-&gt;run() at phar:///usr/local/bin/composer/src/Composer/Console/Application.php:103
   Composer\Console\Application-&gt;run() at phar:///usr/local/bin/composer/bin/composer:56
   require() at /usr/local/bin/composer:24
  </code></pre>