Add getService (#9)

* Add getService

* eh

* type tests

test-app/package.json

@@ -114,6 +114,7 @@
     "edition": "octane"
   },
   "dependencies": {
-    "ember-primitives": "^0.11.3"
+    "ember-primitives": "^0.11.3",
+    "expect-type": "^0.18.0"
   }
 }

test-app/tests/acceptance/get-service-test.ts

@@ -0,0 +1,17 @@
+import { module, test } from 'qunit';
+import { setupApplicationTest } from 'ember-qunit';
+import { expectTypeOf } from 'expect-type';
+
+import { getService } from '@universal-ember/test-support';
+import RouterService from '@ember/routing/router-service';
+
+module('getService', function (hooks) {
+  setupApplicationTest(hooks);
+
+  test('gets the service', async function (assert) {
+    const router = getService('router');
+    expectTypeOf(router).toEqualTypeOf<RouterService>();
+
+    assert.ok(router);
+  });
+});

test-support/src/container/get-service.ts

@@ -0,0 +1,19 @@
+import { assert } from '@ember/debug';
+import type { Registry as ServiceRegistry } from '@ember/service';
+import { getContext } from '@ember/test-helpers';
+import { getOwner } from '@ember/owner';
+import type Owner from '@ember/owner';
+
+export function getService<ServiceName extends keyof ServiceRegistry>(
+  name: ServiceName,
+): ServiceRegistry[ServiceName] {
+  const context = getContext() as { owner?: Owner } | undefined;
+  assert('Could not determine the context for the test', context);
+
+  const owner = context.owner || getOwner(context);
+  assert('Could not find the owner on the context', owner);
+
+  const service = owner.lookup(`service:${name}`);
+
+  return service;
+}

test-support/src/index.ts

@@ -1 +1,2 @@
 export { visitAllLinks } from './routing/visit-all.ts';
+export { getService } from './container/get-service.ts';