diff --git a/core/modules/system/lib/Drupal/system/Tests/Menu/LinksTest.php b/core/modules/system/lib/Drupal/system/Tests/Menu/LinksTest.php
index 5df9629..bcf7c96 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Menu/LinksTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Menu/LinksTest.php
@@ -246,18 +246,18 @@ public function testRouterIntegration() {
       'link_path' => 'router_test/test1',
     ));
     $menu_link->save();
-    $this->assertEqual($menu_link->route_name, 'router_test_1');
+    $this->assertEqual($menu_link->route_name, 'router_test.1');
     $this->assertEqual($menu_link->route_parameters, array());
 
     $menu_link = entity_create('menu_link', array(
       'link_path' => 'router_test/test3/test',
     ));
     $menu_link->save();
-    $this->assertEqual($menu_link->route_name, 'router_test_3');
+    $this->assertEqual($menu_link->route_name, 'router_test.3');
     $this->assertEqual($menu_link->route_parameters, array('value' => 'test'));
 
     $menu_link = entity_load('menu_link', $menu_link->id());
-    $this->assertEqual($menu_link->route_name, 'router_test_3');
+    $this->assertEqual($menu_link->route_name, 'router_test.3');
     $this->assertEqual($menu_link->route_parameters, array('value' => 'test'));
   }
 
diff --git a/core/modules/system/lib/Drupal/system/Tests/Routing/RouterPermissionTest.php b/core/modules/system/lib/Drupal/system/Tests/Routing/RouterPermissionTest.php
index 5541b9f..060303a 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Routing/RouterPermissionTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Routing/RouterPermissionTest.php
@@ -39,7 +39,7 @@ public function testPermissionAccess() {
     $this->assertResponse(403, "Access denied for a route where we don't have a permission");
     // An invalid path should throw an exception.
     $map = array();
-    $route = \Drupal::service('router.route_provider')->getRouteByName('router_test_7');
+    $route = \Drupal::service('router.route_provider')->getRouteByName('router_test.7');
     try {
       menu_item_route_access($route, $path . 'invalid', $map);
       $exception = FALSE;
diff --git a/core/modules/system/tests/modules/condition_test/condition_test.routing.yml b/core/modules/system/tests/modules/condition_test/condition_test.routing.yml
index d242511..bf497e0 100644
--- a/core/modules/system/tests/modules/condition_test/condition_test.routing.yml
+++ b/core/modules/system/tests/modules/condition_test/condition_test.routing.yml
@@ -1,4 +1,4 @@
-condition_test_1:
+condition_test.1:
   pattern: '/condition_test'
   defaults:
     _form: '\Drupal\condition_test\FormController'
diff --git a/core/modules/system/tests/modules/router_test/lib/Drupal/router_test/RouteTestSubscriber.php b/core/modules/system/tests/modules/router_test/lib/Drupal/router_test/RouteTestSubscriber.php
index 4243f81..cc63d39 100644
--- a/core/modules/system/tests/modules/router_test/lib/Drupal/router_test/RouteTestSubscriber.php
+++ b/core/modules/system/tests/modules/router_test/lib/Drupal/router_test/RouteTestSubscriber.php
@@ -38,7 +38,7 @@ public function dynamicRoutes(RouteBuildEvent $event) {
     ), array(
       '_access' => 'TRUE'
     ));
-    $collection->add('router_test_5', $route);
+    $collection->add('router_test.5', $route);
   }
 
   /**
@@ -53,7 +53,7 @@ public function dynamicRoutes(RouteBuildEvent $event) {
   public function alterRoutes(RouteBuildEvent $event) {
     if ($event->getModule() == 'router_test') {
       $collection = $event->getRouteCollection();
-      $route = $collection->get('router_test_6');
+      $route = $collection->get('router_test.6');
       // Change controller method from test1 to test5.
       $route->setDefault('_controller', '\Drupal\router_test\TestControllers::test5');
     }
diff --git a/core/modules/system/tests/modules/router_test/router_test.routing.yml b/core/modules/system/tests/modules/router_test/router_test.routing.yml
index dc6c5a7..a6f55a7 100644
--- a/core/modules/system/tests/modules/router_test/router_test.routing.yml
+++ b/core/modules/system/tests/modules/router_test/router_test.routing.yml
@@ -1,25 +1,25 @@
-router_test_1:
+router_test.1:
   pattern: '/router_test/test1'
   defaults:
     _controller: '\Drupal\router_test\TestControllers::test1'
   requirements:
     _access: 'TRUE'
 
-router_test_2:
+router_test.2:
   pattern: '/router_test/test2'
   defaults:
     _content: '\Drupal\router_test\TestControllers::test2'
   requirements:
     _access: 'TRUE'
 
-router_test_3:
+router_test.3:
   pattern: '/router_test/test3/{value}'
   defaults:
     _content: '\Drupal\router_test\TestControllers::test3'
   requirements:
     _access: 'TRUE'
 
-router_test_4:
+router_test.4:
   pattern: '/router_test/test4/{value}'
   defaults:
     _content: '\Drupal\router_test\TestControllers::test4'
@@ -27,26 +27,26 @@ router_test_4:
   requirements:
     _access: 'TRUE'
 
-router_test_6:
+router_test.6:
   pattern: '/router_test/test6'
   defaults:
     _controller: '\Drupal\router_test\TestControllers::test1'
   requirements:
     _access: 'TRUE'
 
-router_test_7:
+router_test.7:
   pattern: '/router_test/test7'
   defaults:
     _controller: '\Drupal\router_test\TestControllers::test7'
   requirements:
     _permission: 'access test7'
 
-router_test_8:
+router_test.8:
   pattern: '/router_test/test8'
   defaults:
     _controller: '\Drupal\router_test\TestControllers::test8'
 
-router_test_9:
+router_test.9:
   pattern: '/router_test/test9'
   defaults:
     _controller: '\Drupal\router_test\TestControllers::test8'
@@ -54,14 +54,14 @@ router_test_9:
     _permission: 'access test7'
     _access_router_test: 'TRUE'
 
-router_test_10:
+router_test.10:
   pattern: '/router_test/test10'
   defaults:
     _content: '\Drupal\router_test\TestContent::test1'
   requirements:
     _access: 'TRUE'
 
-router_test_11:
+router_test.11:
   pattern: '/router_test/test11'
   options:
     _auth: [ 'http_basic' ]
@@ -70,14 +70,14 @@ router_test_11:
   defaults:
     _content: '\Drupal\router_test\TestContent::test11'
 
-router_test_12:
+router_test.12:
   pattern: '/router_test/test12/{user}'
   requirements:
     _access: 'TRUE'
   defaults:
     _content: '\Drupal\router_test\TestContent::subrequestTest'
 
-router_test_13:
+router_test.13:
   pattern: '/router_test/test13/{user}'
   requirements:
     _access: 'TRUE'