feat(store): add object-style StoreModule.forFeature overload w/fixes (#2885)

* feat(store): add object-style StoreModule.forFeature overload (#2821)

Closes #2809

* fix(store): update StoreModule to be compliant with AOT

Co-authored-by: Suguru Inatomi <suguru.inatomi@gmail.com>

Author: brandonroberts

modules/store/spec/modules.spec.ts

@@ -216,4 +216,34 @@ describe(`Store Modules`, () => {
       });
     });
   });
+
+  describe(`: With slice object`, () => {
+    @NgModule({
+      imports: [
+        StoreModule.forFeature({ name: 'a', reducer: featureAReducer }),
+      ],
+    })
+    class FeatureAModule {}
+
+    @NgModule({
+      imports: [StoreModule.forRoot({}), FeatureAModule],
+    })
+    class RootModule {}
+
+    beforeEach(() => {
+      TestBed.configureTestingModule({
+        imports: [RootModule],
+      });
+
+      store = TestBed.inject(Store);
+    });
+
+    it('should set up a feature state', () => {
+      store.pipe(take(1)).subscribe((state: State) => {
+        expect(state).toEqual({
+          a: 5,
+        } as State);
+      });
+    });
+  });
 });

modules/store/src/index.ts

@@ -55,5 +55,6 @@ export {
   StoreFeatureModule,
   RootStoreConfig,
   StoreConfig,
+  FeatureSlice,
 } from './store_module';
 export { On, on, createReducer } from './reducer_creator';

modules/store/src/store_module.ts

@@ -114,6 +114,14 @@ export interface RootStoreConfig<T, V extends Action = Action>
   runtimeChecks?: Partial<RuntimeChecks>;
 }
 
+/**
+ * An object with the name and the reducer for the feature.
+ */
+export interface FeatureSlice<T, V extends Action = Action> {
+  name: string;
+  reducer: ActionReducer<T, V>;
+}
+
 @NgModule({})
 export class StoreModule {
   static forRoot<T, V extends Action = Action>(
@@ -192,13 +200,19 @@ export class StoreModule {
     reducer: ActionReducer<T, V> | InjectionToken<ActionReducer<T, V>>,
     config?: StoreConfig<T, V> | InjectionToken<StoreConfig<T, V>>
   ): ModuleWithProviders<StoreFeatureModule>;
+  static forFeature<T, V extends Action = Action>(
+    slice: FeatureSlice<T, V>,
+    config?: StoreConfig<T, V> | InjectionToken<StoreConfig<T, V>>
+  ): ModuleWithProviders<StoreFeatureModule>;
   static forFeature(
-    featureName: string,
-    reducers:
+    featureNameOrSlice: string | FeatureSlice<any, any>,
+    reducersOrConfig?:
       | ActionReducerMap<any, any>
       | InjectionToken<ActionReducerMap<any, any>>
       | ActionReducer<any, any>
-      | InjectionToken<ActionReducer<any, any>>,
+      | InjectionToken<ActionReducer<any, any>>
+      | StoreConfig<any, any>
+      | InjectionToken<StoreConfig<any, any>>,
     config: StoreConfig<any, any> | InjectionToken<StoreConfig<any, any>> = {}
   ): ModuleWithProviders<StoreFeatureModule> {
     return {
@@ -207,13 +221,16 @@ export class StoreModule {
         {
           provide: _FEATURE_CONFIGS,
           multi: true,
-          useValue: config,
+          useValue: typeof featureNameOrSlice === 'string' ? config : {},
         },
         {
           provide: STORE_FEATURES,
           multi: true,
           useValue: {
-            key: featureName,
+            key:
+              typeof featureNameOrSlice === 'string'
+                ? featureNameOrSlice
+                : featureNameOrSlice.name,
             reducerFactory:
               !(config instanceof InjectionToken) && config.reducerFactory
                 ? config.reducerFactory
@@ -233,12 +250,21 @@ export class StoreModule {
           deps: [Injector, _FEATURE_CONFIGS, STORE_FEATURES],
           useFactory: _createFeatureStore,
         },
-        { provide: _FEATURE_REDUCERS, multi: true, useValue: reducers },
+        {
+          provide: _FEATURE_REDUCERS,
+          multi: true,
+          useValue:
+            typeof featureNameOrSlice === 'string'
+              ? reducersOrConfig
+              : featureNameOrSlice.reducer,
+        },
         {
           provide: _FEATURE_REDUCERS_TOKEN,
           multi: true,
           useExisting:
-            reducers instanceof InjectionToken ? reducers : _FEATURE_REDUCERS,
+            reducersOrConfig instanceof InjectionToken
+              ? reducersOrConfig
+              : _FEATURE_REDUCERS,
         },
         {
           provide: FEATURE_REDUCERS,

projects/example-app/src/app/auth/auth.module.ts

@@ -26,7 +26,10 @@ export const COMPONENTS = [
     ReactiveFormsModule,
     MaterialModule,
     AuthRoutingModule,
-    StoreModule.forFeature(fromAuth.authFeatureKey, fromAuth.reducers),
+    StoreModule.forFeature({
+      name: fromAuth.authFeatureKey,
+      reducer: fromAuth.reducers,
+    }),
     EffectsModule.forFeature([AuthEffects]),
   ],
   declarations: COMPONENTS,