diff --git a/core/modules/config/src/Tests/ConfigInstallWebTest.php b/core/modules/config/src/Tests/ConfigInstallWebTest.php
index 776daa411bcea80636bb46060eccdbd7897faa2b..a3be6964768fdacc8cde23594a67a0eb3522c330 100644
--- a/core/modules/config/src/Tests/ConfigInstallWebTest.php
+++ b/core/modules/config/src/Tests/ConfigInstallWebTest.php
@@ -137,14 +137,14 @@ function testInstallProfileConfigOverwrite() {
     // Turn on the test module, which will attempt to replace the
     // configuration data. This attempt to replace the active configuration
     // should be ignored.
-    \Drupal::moduleHandler()->install(array('config_override_test'));
+    \Drupal::moduleHandler()->install(array('config_existing_default_config_test'));
 
     // Verify that the test module has not been able to change the data.
     $config = \Drupal::config($config_name);
     $this->assertIdentical($config->get(), $expected_profile_data);
 
     // Disable and uninstall the test module.
-    \Drupal::moduleHandler()->uninstall(array('config_override_test'));
+    \Drupal::moduleHandler()->uninstall(array('config_existing_default_config_test'));
 
     // Verify that the data hasn't been altered by removing the test module.
     $config = \Drupal::config($config_name);
diff --git a/core/modules/config/src/Tests/ConfigModuleOverridesTest.php b/core/modules/config/src/Tests/ConfigModuleOverridesTest.php
index c5c7190c378887e3d05b740c838bdcb242ee402a..1c358c53c5ea5c0a5d1c1c09d50073984dbaf414 100644
--- a/core/modules/config/src/Tests/ConfigModuleOverridesTest.php
+++ b/core/modules/config/src/Tests/ConfigModuleOverridesTest.php
@@ -14,7 +14,7 @@
  */
 class ConfigModuleOverridesTest extends DrupalUnitTestBase {
 
-  public static $modules = array('system', 'config', 'config_override');
+  public static $modules = array('system', 'config', 'config_override_test');
 
   public static function getInfo() {
     return array(
@@ -55,11 +55,11 @@ public function testSimpleModuleOverrides() {
     // Test overrides of completely new configuration objects. In normal runtime
     // this should only happen for configuration entities as we should not be
     // creating simple configuration objects on the fly.
-    $config = $config_factory->get('config_override.new');
-    $this->assertTrue($config->isNew(), 'The configuration object config_override.new is new');
+    $config = $config_factory->get('config_override_test.new');
+    $this->assertTrue($config->isNew(), 'The configuration object config_override_test.new is new');
     $this->assertIdentical($config->get('module'), 'override');
     $config_factory->setOverrideState(FALSE);
-    $config = \Drupal::config('config_override.new');
+    $config = \Drupal::config('config_override_test.new');
     $this->assertIdentical($config->get('module'), NULL);
 
     $config_factory->setOverrideState($old_state);
diff --git a/core/modules/config/src/Tests/ConfigOtherModuleTest.php b/core/modules/config/src/Tests/ConfigOtherModuleTest.php
index 9ba92dae587bc11562e0f54a496b87c0a7d2fa39..c819cb6990490d3cf1655f40fd7281306d46f1a4 100644
--- a/core/modules/config/src/Tests/ConfigOtherModuleTest.php
+++ b/core/modules/config/src/Tests/ConfigOtherModuleTest.php
@@ -39,29 +39,29 @@ public function setUp() {
    * Tests enabling the provider of the default configuration first.
    */
   public function testInstallOtherModuleFirst() {
-    $this->moduleHandler->install(array('config_other_module_config'));
+    $this->moduleHandler->install(array('config_other_module_config_test'));
 
     // Check that the config entity doesn't exist before the config_test module
     // is enabled. We cannot use the entity system because the config_test
     // entity type does not exist.
-    $config = $this->container->get('config.factory')->get('config_test.dynamic.other_module');
+    $config = $this->container->get('config.factory')->get('config_test.dynamic.other_module_test');
     $this->assertTrue($config->isNew(), 'Default configuration for other modules is not installed if that module is not enabled.');
 
     // Install the module that provides the entity type. This installs the
     // default configuration.
     $this->moduleHandler->install(array('config_test'));
-    $this->assertTrue(entity_load('config_test', 'other_module', TRUE), 'Default configuration has been installed.');
+    $this->assertTrue(entity_load('config_test', 'other_module_test', TRUE), 'Default configuration has been installed.');
 
     // Uninstall the module that provides the entity type. This will remove the
     // default configuration.
     $this->moduleHandler->uninstall(array('config_test'));
-    $config = $this->container->get('config.factory')->get('config_test.dynamic.other_module');
+    $config = $this->container->get('config.factory')->get('config_test.dynamic.other_module_test');
     $this->assertTrue($config->isNew(), 'Default configuration for other modules is removed when the config entity provider is disabled.');
 
     // Install the module that provides the entity type again. This installs the
     // default configuration.
     $this->moduleHandler->install(array('config_test'));
-    $other_module_config_entity = entity_load('config_test', 'other_module', TRUE);
+    $other_module_config_entity = entity_load('config_test', 'other_module_test', TRUE);
     $this->assertTrue($other_module_config_entity, "Default configuration has been recreated.");
 
     // Update the default configuration to test that the changes are preserved
@@ -70,15 +70,15 @@ public function testInstallOtherModuleFirst() {
     $other_module_config_entity->save();
 
     // Uninstall the module that provides the default configuration.
-    $this->moduleHandler->uninstall(array('config_other_module_config'));
-    $this->assertTrue(entity_load('config_test', 'other_module', TRUE), 'Default configuration for other modules is not removed when the module that provides it is uninstalled.');
+    $this->moduleHandler->uninstall(array('config_other_module_config_test'));
+    $this->assertTrue(entity_load('config_test', 'other_module_test', TRUE), 'Default configuration for other modules is not removed when the module that provides it is uninstalled.');
 
     // Default configuration provided by config_test should still exist.
     $this->assertTrue(entity_load('config_test', 'dotted.default', TRUE), 'The configuration is not deleted.');
 
     // Re-enable module to test that default config is unchanged.
-    $this->moduleHandler->install(array('config_other_module_config'));
-    $config_entity = entity_load('config_test', 'other_module', TRUE);
+    $this->moduleHandler->install(array('config_other_module_config_test'));
+    $config_entity = entity_load('config_test', 'other_module_test', TRUE);
     $this->assertEqual($config_entity->get('style'), "The piano ain't got no wrong notes.", 'Re-enabling the module does not install default config over the existing config entity.');
   }
 
@@ -87,10 +87,10 @@ public function testInstallOtherModuleFirst() {
    */
   public function testInstallConfigEnityModuleFirst() {
     $this->moduleHandler->install(array('config_test'));
-    $this->assertFalse(entity_load('config_test', 'other_module', TRUE), 'Default configuration provided by config_other_module_config does not exist.');
+    $this->assertFalse(entity_load('config_test', 'other_module_test', TRUE), 'Default configuration provided by config_other_module_config_test does not exist.');
 
-    $this->moduleHandler->install(array('config_other_module_config'));
-    $this->assertTrue(entity_load('config_test', 'other_module', TRUE), 'Default configuration provided by config_other_module_config has been installed.');
+    $this->moduleHandler->install(array('config_other_module_config_test'));
+    $this->assertTrue(entity_load('config_test', 'other_module_test', TRUE), 'Default configuration provided by config_other_module_config_test has been installed.');
   }
 
   /**
diff --git a/core/modules/config/src/Tests/ConfigOverridesPriorityTest.php b/core/modules/config/src/Tests/ConfigOverridesPriorityTest.php
index 6deab96dff6f83b162c88a1c82c0c3d2b3b73d05..44a4180c3addfb6c41eedd2908c74d13ecc264f9 100644
--- a/core/modules/config/src/Tests/ConfigOverridesPriorityTest.php
+++ b/core/modules/config/src/Tests/ConfigOverridesPriorityTest.php
@@ -15,7 +15,7 @@
  */
 class ConfigOverridesPriorityTest extends DrupalUnitTestBase {
 
-  public static $modules = array('system', 'config', 'config_override', 'language');
+  public static $modules = array('system', 'config', 'config_override_test', 'language');
 
   public static function getInfo() {
     return array(
diff --git a/core/modules/config/tests/config_existing_default_config_test/config_existing_default_config_test.yml b/core/modules/config/tests/config_existing_default_config_test/config_existing_default_config_test.yml
new file mode 100644
index 0000000000000000000000000000000000000000..4163a8502af09456566145cd0fc8f8339b2db643
--- /dev/null
+++ b/core/modules/config/tests/config_existing_default_config_test/config_existing_default_config_test.yml
@@ -0,0 +1,6 @@
+name: 'Configuration existing default config test'
+type: module
+package: Testing
+version: VERSION
+core: 8.x
+hidden: true
diff --git a/core/modules/config/tests/config_other_module_config/config/install/config_test.dynamic.other_module.yml b/core/modules/config/tests/config_other_module_config_test/config/install/config_test.dynamic.other_module_test.yml
similarity index 60%
rename from core/modules/config/tests/config_other_module_config/config/install/config_test.dynamic.other_module.yml
rename to core/modules/config/tests/config_other_module_config_test/config/install/config_test.dynamic.other_module_test.yml
index b56ac6d3300a0035ef518530cfbc72cc2ba728e7..a43f3a0a97ffa0e36438dc74532aa408c81d3b8f 100644
--- a/core/modules/config/tests/config_other_module_config/config/install/config_test.dynamic.other_module.yml
+++ b/core/modules/config/tests/config_other_module_config_test/config/install/config_test.dynamic.other_module_test.yml
@@ -1,5 +1,5 @@
-id: other_module
-label: 'Other module'
+id: other_module_test
+label: 'Other module test'
 weight: 0
 style: ''
 status: true
diff --git a/core/modules/config/tests/config_other_module_config/config_other_module_config.info.yml b/core/modules/config/tests/config_other_module_config_test/config_other_module_config_test.info.yml
similarity index 100%
rename from core/modules/config/tests/config_other_module_config/config_other_module_config.info.yml
rename to core/modules/config/tests/config_other_module_config_test/config_other_module_config_test.info.yml
diff --git a/core/modules/config/tests/config_override/config_override.services.yml b/core/modules/config/tests/config_override/config_override.services.yml
deleted file mode 100644
index 5272a84a20e1fb6aaadf490d9e1c967a49b5cce2..0000000000000000000000000000000000000000
--- a/core/modules/config/tests/config_override/config_override.services.yml
+++ /dev/null
@@ -1,9 +0,0 @@
-services:
-  config_override.overrider:
-    class: Drupal\config_override\ConfigOverrider
-    tags:
-      - { name: config.factory.override}
-  config_override.low_priority_overrider:
-    class: Drupal\config_override\ConfigOverriderLowPriority
-    tags:
-      - { name: config.factory.override, priority: -100 }
diff --git a/core/modules/config/tests/config_override/config_override.info.yml b/core/modules/config/tests/config_override_test/config_override_test.info.yml
similarity index 100%
rename from core/modules/config/tests/config_override/config_override.info.yml
rename to core/modules/config/tests/config_override_test/config_override_test.info.yml
diff --git a/core/modules/config/tests/config_override_test/config_override_test.module b/core/modules/config/tests/config_override_test/config_override_test.module
deleted file mode 100644
index f364ffb12c7d04af3d213f0136a8f2f4ef166dbc..0000000000000000000000000000000000000000
--- a/core/modules/config/tests/config_override_test/config_override_test.module
+++ /dev/null
@@ -1,6 +0,0 @@
-<?php
-
-/**
- * @file
- * Test module containing a configuration file which matches another module.
- */
diff --git a/core/modules/config/tests/config_override_test/config_override_test.services.yml b/core/modules/config/tests/config_override_test/config_override_test.services.yml
new file mode 100644
index 0000000000000000000000000000000000000000..c3fae649167936c8f42853aa999d4c154ef3cbc8
--- /dev/null
+++ b/core/modules/config/tests/config_override_test/config_override_test.services.yml
@@ -0,0 +1,9 @@
+services:
+  config_override_test.overrider:
+    class: Drupal\config_override_test\ConfigOverrider
+    tags:
+      - { name: config.factory.override}
+  config_override_test.low_priority_overrider:
+    class: Drupal\config_override_test\ConfigOverriderLowPriority
+    tags:
+      - { name: config.factory.override, priority: -100 }
diff --git a/core/modules/config/tests/config_override_test/config_override_test.yml b/core/modules/config/tests/config_override_test/config_override_test.yml
deleted file mode 100644
index f1f1109cc29e964d12b032c2a1e4a7076122e9e2..0000000000000000000000000000000000000000
--- a/core/modules/config/tests/config_override_test/config_override_test.yml
+++ /dev/null
@@ -1,5 +0,0 @@
-name: 'Configuration override test'
-type: module
-package: Testing
-version: VERSION
-core: 8.x
diff --git a/core/modules/config/tests/config_override/src/ConfigOverrider.php b/core/modules/config/tests/config_override_test/src/ConfigOverrider.php
similarity index 65%
rename from core/modules/config/tests/config_override/src/ConfigOverrider.php
rename to core/modules/config/tests/config_override_test/src/ConfigOverrider.php
index 1da4ed7bc6aa051f4035e4d7c943bc39246f9841..8eb383604b7c61a8770e68af927d1cac9d147170 100644
--- a/core/modules/config/tests/config_override/src/ConfigOverrider.php
+++ b/core/modules/config/tests/config_override_test/src/ConfigOverrider.php
@@ -2,16 +2,12 @@
 
 /**
  * @file
- * Contains \Drupal\config_override\ConfigOverrider.
+ * Contains \Drupal\config_override_test\ConfigOverrider.
  */
 
-namespace Drupal\config_override;
+namespace Drupal\config_override_test;
 
-use Drupal\Core\Config\ConfigEvents;
 use Drupal\Core\Config\ConfigFactoryOverrideInterface;
-use Drupal\Core\Config\ConfigModuleOverridesEvent;
-use Drupal\Core\Config\StorageInterface;
-use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 
 /**
  * Tests module overrides for configuration.
@@ -27,8 +23,8 @@ public function loadOverrides($names) {
       if (in_array('system.site', $names)) {
         $overrides = $overrides + array('system.site' => array('name' => 'ZOMG overridden site name'));
       }
-      if (in_array('config_override.new', $names)) {
-        $overrides = $overrides + array('config_override.new' => array('module' => 'override'));
+      if (in_array('config_override_test.new', $names)) {
+        $overrides = $overrides + array('config_override_test.new' => array('module' => 'override'));
       }
     }
     return $overrides;
diff --git a/core/modules/config/tests/config_override/src/ConfigOverriderLowPriority.php b/core/modules/config/tests/config_override_test/src/ConfigOverriderLowPriority.php
similarity index 91%
rename from core/modules/config/tests/config_override/src/ConfigOverriderLowPriority.php
rename to core/modules/config/tests/config_override_test/src/ConfigOverriderLowPriority.php
index 16aa406a744092c818e7130a391fd4ebab7495cd..6b11e0a09855a0fb7a7a0a81ca2d11c72b9ee8f4 100644
--- a/core/modules/config/tests/config_override/src/ConfigOverriderLowPriority.php
+++ b/core/modules/config/tests/config_override_test/src/ConfigOverriderLowPriority.php
@@ -2,10 +2,10 @@
 
 /**
  * @file
- * Contains \Drupal\config_override\ConfigOverriderLowPriority.
+ * Contains \Drupal\config_override_test\ConfigOverriderLowPriority.
  */
 
-namespace Drupal\config_override;
+namespace Drupal\config_override_test;
 
 use Drupal\Core\Config\ConfigFactoryOverrideInterface;
 use Drupal\Core\Config\StorageInterface;
diff --git a/core/modules/config/tests/config_test_invalid_name/config/install/invalid_object_name.yml b/core/modules/config/tests/config_test_invalid_name/config/install/invalid_object_name.yml
deleted file mode 100644
index f3f2ba0e014efdc488a93c32be450b955fbf4ed7..0000000000000000000000000000000000000000
--- a/core/modules/config/tests/config_test_invalid_name/config/install/invalid_object_name.yml
+++ /dev/null
@@ -1 +0,0 @@
-frittata: potato
diff --git a/core/modules/config/tests/config_test_invalid_name/config/schema/config_test_invalid_name.schema.yml b/core/modules/config/tests/config_test_invalid_name/config/schema/config_test_invalid_name.schema.yml
deleted file mode 100644
index 1f541b153e5a01180954ddbd09dd5e47d6799749..0000000000000000000000000000000000000000
--- a/core/modules/config/tests/config_test_invalid_name/config/schema/config_test_invalid_name.schema.yml
+++ /dev/null
@@ -1,9 +0,0 @@
-# Schema for the configuration files of the Invalid Configuration Name module.
-
-invalid_object_name:
-  type: mapping
-  label: 'Invalid configuration'
-  mapping:
-    frittata:
-      type: string
-      label: 'String'
diff --git a/core/modules/config/tests/config_test_invalid_name/install b/core/modules/config/tests/config_test_invalid_name/install
deleted file mode 100644
index 91ed0ae748d119a4cf90adf481d5c0627f65df84..0000000000000000000000000000000000000000
--- a/core/modules/config/tests/config_test_invalid_name/install
+++ /dev/null
@@ -1,5 +0,0 @@
-name: 'Invalid configuration name'
-type: module
-package: Core
-version: VERSION
-core: 8.x