Lazily setup the router in non-application tests for <LinkTo> component

packages/@ember/-internals/glimmer/tests/integration/components/link-to/rendering-angle-test.js

@@ -101,7 +101,11 @@ moduleFor(
     ['@test should be able to be inserted in DOM when the router is not present - block']() {
       this.render(`<LinkTo @route='index'>Go to Index</LinkTo>`);
 
-      this.assertText('Go to Index');
+      this.assertComponentElement(this.element.firstChild, {
+        tagName: 'a',
+        attrs: { href: '#/' },
+        content: 'Go to Index',
+      });
     }
   }
 );

packages/@ember/-internals/routing/lib/services/routing.ts

@@ -2,12 +2,16 @@
 @module ember
 */
 
+import { getOwner, Owner } from '@ember/-internals/owner';
+import { symbol } from '@ember/-internals/utils';
 import { readOnly } from '@ember/object/computed';
 import { assign } from '@ember/polyfills';
 import Service from '@ember/service';
 import EmberRouter, { QueryParam } from '../system/router';
 import RouterState from '../system/router_state';
 
+const ROUTER = symbol('ROUTER') as string;
+
 /**
   The Routing service is used by LinkComponent, and provides facilities for
   the component/view layer to interact with the router.
@@ -19,7 +23,17 @@ import RouterState from '../system/router_state';
   @class RoutingService
 */
 export default class RoutingService extends Service {
-  router!: EmberRouter;
+  get router(): EmberRouter {
+    let router = this[ROUTER];
+    if (router !== undefined) {
+      return router;
+    }
+    const owner = getOwner(this) as Owner;
+    router = owner.lookup('router:main') as EmberRouter;
+    router.setupRouter();
+    return (this[ROUTER] = router);
+  }
+
   hasRoute(routeName: string) {
     return this.router.hasRoute(routeName);
   }

packages/@ember/application/tests/application_test.js

@@ -156,7 +156,6 @@ moduleFor(
       verifyRegistration(assert, application, 'component:textarea');
 
       verifyRegistration(assert, application, 'service:-routing');
-      verifyInjection(assert, application, 'service:-routing', 'router', 'router:main');
 
       // DEBUGGING
       verifyRegistration(assert, application, 'resolver-for-debugging:main');

packages/@ember/engine/index.js

@@ -511,8 +511,6 @@ function commonSetupRegistry(registry) {
 
   // Register the routing service...
   registry.register('service:-routing', RoutingService);
-  // Then inject the app router into it
-  registry.injection('service:-routing', 'router', 'router:main');
 
   // DEBUGGING
   registry.register('resolver-for-debugging:main', registry.resolver, {

packages/@ember/engine/tests/engine_test.js

@@ -81,7 +81,6 @@ moduleFor(
       verifyRegistration(assert, engine, 'component:textarea');
 
       verifyRegistration(assert, engine, 'service:-routing');
-      verifyInjection(assert, engine, 'service:-routing', 'router', 'router:main');
 
       // DEBUGGING
       verifyRegistration(assert, engine, 'resolver-for-debugging:main');

packages/ember/tests/routing/query_params_test/query_param_async_get_handler_test.js

@@ -21,28 +21,31 @@ moduleFor(
         },
 
         setupRouter() {
-          this._super(...arguments);
-          let { _handlerPromises: handlerPromises, _seenHandlers: seenHandlers } = this;
-          let getRoute = this._routerMicrolib.getRoute;
-
-          this._routerMicrolib.getRoute = function (routeName) {
-            fetchedHandlers.push(routeName);
-
-            // Cache the returns so we don't have more than one Promise for a
-            // given handler.
-            return (
-              handlerPromises[routeName] ||
-              (handlerPromises[routeName] = new RSVP.Promise((resolve) => {
-                setTimeout(() => {
-                  let handler = getRoute(routeName);
-
-                  seenHandlers[routeName] = handler;
-
-                  resolve(handler);
-                }, 10);
-              }))
-            );
-          };
+          let isNewSetup = this._super(...arguments);
+          if (isNewSetup) {
+            let { _handlerPromises: handlerPromises, _seenHandlers: seenHandlers } = this;
+            let getRoute = this._routerMicrolib.getRoute;
+
+            this._routerMicrolib.getRoute = function (routeName) {
+              fetchedHandlers.push(routeName);
+
+              // Cache the returns so we don't have more than one Promise for a
+              // given handler.
+              return (
+                handlerPromises[routeName] ||
+                (handlerPromises[routeName] = new RSVP.Promise((resolve) => {
+                  setTimeout(() => {
+                    let handler = getRoute(routeName);
+
+                    seenHandlers[routeName] = handler;
+
+                    resolve(handler);
+                  }, 10);
+                }))
+              );
+            };
+          }
+          return isNewSetup;
         },
 
         _getQPMeta(routeInfo) {