fix: fix check which ensures that Workbench.forRoot() is not used i…

…n a lazy context

Issue: `Workbench.forChild()` failed if being used from a lazy loaded module.

fixes #5

projects/scion/workbench/src/lib/workbench.constants.ts

@@ -25,6 +25,11 @@ export const ROUTER_OUTLET_NAME = new InjectionToken<string>('ROUTER_OUTLET_NAME
  */
 export const ROUTE_REUSE_PROVIDER = new InjectionToken<WbRouteReuseProvider>('ROUTE_REUSE_PROVIDER');
 
+/**
+ * DI injection token to ensure `WorkbenchModule.forRoot()` is not used in a lazy context.
+ */
+export const WORKBENCH_FORROOT_GUARD = new InjectionToken<void>('WORKBENCH_FORROOT_GUARD');
+
 /**
  * Represents the name of the activity router outlet.
  */

projects/scion/workbench/src/lib/workbench.module.ts

@@ -8,7 +8,7 @@
  *  SPDX-License-Identifier: EPL-2.0
  */
 
-import { ANALYZE_FOR_ENTRY_COMPONENTS, InjectionToken, ModuleWithProviders, NgModule, Optional, SkipSelf } from '@angular/core';
+import { ANALYZE_FOR_ENTRY_COMPONENTS, Inject, InjectionToken, ModuleWithProviders, NgModule, Optional, SkipSelf } from '@angular/core';
 import { CommonModule } from '@angular/common';
 
 import { WorkbenchComponent } from './workbench.component';
@@ -49,7 +49,7 @@ import { WbActivityDirective } from './activity-part/wb-activity.directive';
 import { MoveDirective } from './move.directive';
 import { WorkbenchConfig } from './workbench.config';
 import { OverlayTemplateOutletDirective } from './overlay-template-outlet.directive';
-import { ROUTE_REUSE_PROVIDER } from './workbench.constants';
+import { ROUTE_REUSE_PROVIDER, WORKBENCH_FORROOT_GUARD } from './workbench.constants';
 import { NotificationService } from './notification/notification.service';
 import { NotificationListComponent } from './notification/notification-list.component';
 import { NotificationComponent } from './notification/notification.component';
@@ -117,10 +117,8 @@ const CONFIG = new InjectionToken<WorkbenchConfig>('WORKBENCH_CONFIG');
 })
 export class WorkbenchModule {
 
-  // Specify services to be instantiated eagerly
-  constructor(@Optional() @SkipSelf() parentModule: WorkbenchModule,
-              viewRegistrySynchronizer: ViewRegistrySynchronizer) {
-    WorkbenchModule.throwIfAlreadyLoaded(parentModule);
+  // Note: We are injecting ViewRegistrySynchronizer so it gets created eagerly...
+  constructor(@Optional() @Inject(WORKBENCH_FORROOT_GUARD) guard: any, viewRegistrySynchronizer: ViewRegistrySynchronizer) {
   }
 
   /**
@@ -199,6 +197,11 @@ export class WorkbenchModule {
           provide: RouteReuseStrategy,
           useClass: WbRouteReuseStrategy,
         },
+        {
+          provide: WORKBENCH_FORROOT_GUARD,
+          useFactory: provideForRootGuard,
+          deps: [[WorkbenchService, new Optional(), new SkipSelf()]]
+        },
       ]
     };
   }
@@ -212,12 +215,13 @@ export class WorkbenchModule {
       providers: [] // do not register any providers in 'forChild' but in 'forRoot' instead
     };
   }
+}
 
-  private static throwIfAlreadyLoaded(parentModule: any): void {
-    if (parentModule) {
-      throw new Error('WorkbenchModule.forRoot() called twice. Lazy loaded modules should use WorkbenchModule.forChild() instead.');
-    }
+export function provideForRootGuard(workbench: WorkbenchService): any {
+  if (workbench) {
+    throw new Error('WorkbenchModule.forRoot() called twice. Lazy loaded modules should use WorkbenchModule.forChild() instead.');
   }
+  return 'guarded';
 }
 
 export function newConfig(config: WorkbenchConfig): WorkbenchConfig {

projects/scion/workbench/src/lib/workbench.spec.ts

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2018 Swiss Federal Railways
+ *
+ * This program and the accompanying materials are made
+ * available under the terms of the Eclipse Public License 2.0
+ * which is available at https://www.eclipse.org/legal/epl-2.0/
+ *
+ *  SPDX-License-Identifier: EPL-2.0
+ */
+
+import { async, fakeAsync, inject, TestBed } from '@angular/core/testing';
+import { Component, NgModule, NgModuleFactoryLoader } from '@angular/core';
+import { RouterTestingModule, SpyNgModuleFactoryLoader } from '@angular/router/testing';
+import { Router, RouterModule } from '@angular/router';
+import { WorkbenchModule } from './workbench.module';
+import { CommonModule } from '@angular/common';
+import { NoopAnimationsModule } from '@angular/platform-browser/animations';
+import { advance } from './routing/testing.spec';
+import { WorkbenchRouter } from './routing/workbench-router.service';
+
+describe('Workbench', () => {
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      imports: [AppTestModule]
+    });
+
+    TestBed.get(Router).initialNavigation();
+  }));
+
+  it('throws an error when forRoot() is used in a lazy context', fakeAsync(inject([WorkbenchRouter, NgModuleFactoryLoader], (wbRouter: WorkbenchRouter, loader: SpyNgModuleFactoryLoader) => {
+    loader.stubbedModules = {
+      './feature-a/feature-a.module#FeatureAModule': FeatureAModule,
+      './feature-b/feature-b.module#FeatureBModule': FeatureBModule,
+    };
+
+    const fixture = TestBed.createComponent(AppComponent);
+    advance(fixture);
+
+    let recordedError: Error = null;
+
+    // Load lazy module with WorkbenchModule.forRoot() import
+    wbRouter.navigate(['wrong-import'], {blankViewPartRef: 'viewpart.1'}).catch(err => recordedError = err);
+    advance(fixture);
+    expect(recordedError.message).toEqual('WorkbenchModule.forRoot() called twice. Lazy loaded modules should use WorkbenchModule.forChild() instead.');
+
+    // Load lazy module with WorkbenchModule.forChild() import
+    recordedError = null;
+    wbRouter.navigate(['correct-import'], {blankViewPartRef: 'viewpart.1'}).catch(err => recordedError = err);
+    advance(fixture);
+    expect(recordedError).toBeNull();
+  })));
+});
+
+/****************************************************************************************************
+ * Definition of App Test Module                                                                    *
+ ****************************************************************************************************/
+@Component({template: '<wb-workbench style="position: relative; width: 100%; height: 500px"></wb-workbench>'})
+class AppComponent {
+}
+
+@NgModule({
+  imports: [
+    WorkbenchModule.forRoot(),
+    NoopAnimationsModule,
+    RouterTestingModule.withRoutes([
+      {path: 'wrong-import', loadChildren: './feature-a/feature-a.module#FeatureAModule'},
+      {path: 'correct-import', loadChildren: './feature-b/feature-b.module#FeatureBModule'},
+    ]),
+  ],
+  declarations: [AppComponent]
+})
+class AppTestModule {
+}
+
+/****************************************************************************************************
+ * Definition of Feature Module A                                                                   *
+ ****************************************************************************************************/
+@Component({template: 'Feature Module A'})
+class ModuleAComponent {
+}
+
+@NgModule({
+  imports: [
+    CommonModule,
+    RouterModule.forChild([{path: '', component: ModuleAComponent}]),
+    WorkbenchModule.forRoot() // simulate wrong import
+  ],
+  declarations: [ModuleAComponent]
+})
+export class FeatureAModule {
+}
+
+/****************************************************************************************************
+ * Definition of Feature Module B                                                                   *
+ ****************************************************************************************************/
+@Component({template: 'Feature Module B'})
+class ModuleBComponent {
+}
+
+@NgModule({
+  imports: [
+    CommonModule,
+    RouterModule.forChild([{path: '', component: ModuleBComponent}]),
+    WorkbenchModule.forChild() // simulate correct import
+  ],
+  declarations: [ModuleBComponent]
+})
+export class FeatureBModule {
+}