diff --git a/core/tests/bootstrap.php b/core/tests/bootstrap.php
index a19c6d8..b82cd22 100644
--- a/core/tests/bootstrap.php
+++ b/core/tests/bootstrap.php
@@ -20,7 +20,8 @@ function drupal_phpunit_find_module_directories($scan_directory) {
   $dir = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($scan_directory, \RecursiveDirectoryIterator::FOLLOW_SYMLINKS));
   foreach ($dir as $d) {
     if (strpos($d->getPathname(), 'info.yml') !== FALSE) {
-      $module_directories[] = $d->getPathInfo()->getRealPath();
+      // Cut of ".info.yml" from the filename and use that as module name.
+      $module_directories[substr($d->getFilename(), 0, -9)] = $d->getPathInfo()->getRealPath();
     }
   }
 
@@ -54,14 +55,14 @@ function drupal_phpunit_find_site_module_directories($sites_path) {
  *   An array of module directories.
  */
 function drupal_phpunit_register_module_dirs(Composer\Autoload\ClassLoader $loader, $dirs) {
-  foreach ($dirs as $dir) {
+  foreach ($dirs as $module => $dir) {
     $lib_path = $dir . '/lib';
     if (is_dir($lib_path)) {
-      $loader->add('Drupal\\' . basename($dir), $lib_path);
+      $loader->add('Drupal\\' . $module, $lib_path);
     }
     $tests_path = $dir . '/tests';
     if (is_dir($tests_path)) {
-      $loader->add('Drupal\\' . basename($dir), $tests_path);
+      $loader->add('Drupal\\' . $module, $tests_path);
     }
   }
 }