diff --git a/core/modules/system/src/Tests/Module/DependencyTest.php b/core/modules/system/tests/src/Functional/Module/DependencyTest.php
similarity index 99%
rename from core/modules/system/src/Tests/Module/DependencyTest.php
rename to core/modules/system/tests/src/Functional/Module/DependencyTest.php
index 173380ebd6..0fc78caa95 100644
--- a/core/modules/system/src/Tests/Module/DependencyTest.php
+++ b/core/modules/system/tests/src/Functional/Module/DependencyTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\system\Tests\Module;
+namespace Drupal\Tests\system\Functional\Module;
 
 use Drupal\Component\Utility\Unicode;
 
diff --git a/core/modules/system/src/Tests/Module/HookRequirementsTest.php b/core/modules/system/tests/src/Functional/Module/HookRequirementsTest.php
similarity index 94%
rename from core/modules/system/src/Tests/Module/HookRequirementsTest.php
rename to core/modules/system/tests/src/Functional/Module/HookRequirementsTest.php
index c89c206ca3..a873d9652a 100644
--- a/core/modules/system/src/Tests/Module/HookRequirementsTest.php
+++ b/core/modules/system/tests/src/Functional/Module/HookRequirementsTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\system\Tests\Module;
+namespace Drupal\Tests\system\Functional\Module;
 
 /**
  * Attempts enabling a module that fails hook_requirements('install').
diff --git a/core/modules/system/src/Tests/Module/InstallUninstallTest.php b/core/modules/system/tests/src/Functional/Module/InstallUninstallTest.php
similarity index 99%
rename from core/modules/system/src/Tests/Module/InstallUninstallTest.php
rename to core/modules/system/tests/src/Functional/Module/InstallUninstallTest.php
index e3c7af2db5..4d8f30d65c 100644
--- a/core/modules/system/src/Tests/Module/InstallUninstallTest.php
+++ b/core/modules/system/tests/src/Functional/Module/InstallUninstallTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\system\Tests\Module;
+namespace Drupal\Tests\system\Functional\Module;
 
 use Drupal\Component\Render\FormattableMarkup;
 use Drupal\Core\Logger\RfcLogLevel;
diff --git a/core/modules/system/src/Tests/Module/PrepareUninstallTest.php b/core/modules/system/tests/src/Functional/Module/PrepareUninstallTest.php
similarity index 97%
rename from core/modules/system/src/Tests/Module/PrepareUninstallTest.php
rename to core/modules/system/tests/src/Functional/Module/PrepareUninstallTest.php
index dd89e31522..86d06e35ee 100644
--- a/core/modules/system/src/Tests/Module/PrepareUninstallTest.php
+++ b/core/modules/system/tests/src/Functional/Module/PrepareUninstallTest.php
@@ -1,17 +1,17 @@
 <?php
 
-namespace Drupal\system\Tests\Module;
+namespace Drupal\Tests\system\Functional\Module;
 
 use Drupal\Component\Utility\Unicode;
-use Drupal\simpletest\WebTestBase;
-use Drupal\taxonomy\Tests\TaxonomyTestTrait;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\taxonomy\Functional\TaxonomyTestTrait;
 
 /**
  * Tests that modules which provide entity types can be uninstalled.
  *
  * @group Module
  */
-class PrepareUninstallTest extends WebTestBase {
+class PrepareUninstallTest extends BrowserTestBase {
 
   use TaxonomyTestTrait;
 
diff --git a/core/modules/system/src/Tests/Module/RequiredTest.php b/core/modules/system/tests/src/Functional/Module/RequiredTest.php
similarity index 95%
rename from core/modules/system/src/Tests/Module/RequiredTest.php
rename to core/modules/system/tests/src/Functional/Module/RequiredTest.php
index a2f3560abd..00c7cbe703 100644
--- a/core/modules/system/src/Tests/Module/RequiredTest.php
+++ b/core/modules/system/tests/src/Functional/Module/RequiredTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\system\Tests\Module;
+namespace Drupal\Tests\system\Functional\Module;
 
 /**
  * Attempt disabling of required modules.
diff --git a/core/modules/system/src/Tests/Module/VersionTest.php b/core/modules/system/tests/src/Functional/Module/VersionTest.php
similarity index 91%
rename from core/modules/system/src/Tests/Module/VersionTest.php
rename to core/modules/system/tests/src/Functional/Module/VersionTest.php
index daad1a6679..7b325fef8f 100644
--- a/core/modules/system/src/Tests/Module/VersionTest.php
+++ b/core/modules/system/tests/src/Functional/Module/VersionTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\system\Tests\Module;
+namespace Drupal\Tests\system\Functional\Module;
 
 /**
  * Tests module version dependencies.
@@ -49,7 +49,7 @@ public function testModuleVersions() {
     for ($i = 0; $i < $n; $i++) {
       $this->drupalGet('admin/modules');
       $checkbox = $this->xpath('//input[@id="edit-modules-module-test-enable"]');
-      $this->assertEqual(!empty($checkbox[0]['disabled']), $i % 2, $dependencies[$i]);
+      $this->assertEqual(!empty($checkbox[0]->getAttribute('disabled')), $i % 2, $dependencies[$i]);
     }
   }