Child state conflict if multiple lazy-loaded states are present

[cyr-x]

🐞 bug report

Affected Package

@loona/angular: 1.0.0

Description

If multiple states are "lazy-loaded" via LoonaModule.forChild, only the latest module import will initialize a child state. This is caused because CHILD_STATE is provided with multi: false option, therefore every call of LoonaModule.forChild will override previous values.

This happens if you have for example multiple feature modules which are imported by the app root module and each of the feature module holds a state by using LoonaModule.forChild.

This can be solved by providing CHILD_STATE with multi: true and changing the effect initialization code inside LoonaChildModule to handle multiple state groups.

@NgModule()
export class LoonaModule {
  // ...
  static forChild(states: any[] = []): ModuleWithProviders {
    return {
      ngModule: LoonaChildModule,
      providers: [
        ...states, 
        { provide: CHILD_STATE, useValue: states, multi: true },
      ],
    };
  }
}


@NgModule()
export class LoonaChildModule {
  constructor(
    @Inject(CHILD_STATE) stateGroups: StateClass<Metadata>[][], // <-- changed
    // ...
  ) {
   // ...

   // Changed to handle CHILD_STATE provider array
    stateGroups.forEach(group =>
    {
      group.forEach(state => {
         // ...
      });
    })
    // ...
  }
}

But this will propaply cause some side-effects because states are instanciated multiple times.

🌍 Your Environment

Angular Version:

Angular CLI: 7.1.4
Node: 10.9.0
OS: linux x64
Angular: 7.1.4
... animations, cli, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.11.4
@angular-devkit/build-angular     0.11.4
@angular-devkit/build-optimizer   0.11.4
@angular-devkit/build-webpack     0.11.4
@angular-devkit/core              7.1.4
@angular-devkit/schematics        7.1.4
@ngtools/webpack                  7.1.4
@schematics/angular               7.1.4
@schematics/update                0.11.4
rxjs                              6.3.3
typescript                        3.2.2
webpack                           4.23.1