store-devtools: cannot read property 'state' of undefined

[alex-okrushko]

I'm submitting a...

[ x ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report  
[ ] Feature request
[ ] Documentation issue or request

What is the current behavior?

After syncing the latest ngrx into Google I have one of the tests failing (it's bootstrapping entire AppModule and has StoreDevtoolsModule.instrument({maxAge: 25}) as part of imports). The test fails to initialize, so none of the actual test code is executed yet.

The issue is surfaced in unliftState when computedStates has length of 2, yet currentStateIndex is 2 as well, and thus computedStates[currentStateIndex] returns undefiend.

This is what was the state leading up to this call:

Expected behavior:

Minimal reproduction of the problem with instructions:

Version of affected browser(s),operating system(s), npm, node and ngrx:

Other information:

[brandonroberts]

@alex-okrushko we are looking into this issue. Is there a certain sequence of events you can reproduce that triggers this issue?

[alex-okrushko]

Not 100% certain, but it appears that StoreDevtoolsModule.instrument({maxAge: 25}) was being imported twice.
@benlesh might have more details (that's his project that's causing troubles :) )

[alex-okrushko]

With one StoreDevtoolsModule everything works.
@brandonroberts do you want it closed? That's a weird case but for some reason it was working before.

[brandonroberts]

@alex-okrushko Yes. How was the second StoreDevtoolsModule introduced? Through another module imported lazily? We could add a guard to prevent it from being loaded more than once, but I'd like to understand how it came in first.

[alex-okrushko]

In the same NgModule through unusual way:

// foo.ts
export const REQUIRED_MODULES = [
   StoreModule.forRoot({}),
   EffectsModule.forRoot([]),
   StoreDevtoolsModule.instrument({maxAge: 25}),
];

// app_module.ts
import {REQUIRED_MODULES} from './foo.ts';

@NgModule({
  declarations: [  ],
  imports: [
    ...REQUIRED_MODULES,
    BrowserAnimationsModule,
    HttpModule,
    StoreDevtoolsModule.instrument({maxAge: 25}),
  ],
})
export class AppModule {}

[ccpony]

I'm having this problem. StoreDevtoolsModule is only being imported once.

[brandonroberts]

@ccpony provide a repo with a reproduction of this issue

[benlesh]

For our part, it was only being provided once as well.

[ccpony]

Yes, I'll prepare a repo. However, what I can tell you now is that the error is triggered on the following line of code:

export const getSupplierState = createFeatureSelector<SupplierState>('suppliers');

...which produced the "cannot read property 'suppliers' of undefined" in the browser.

[alex-okrushko]

@benlesh It was provided twice. I removed the second installation.

[alex-okrushko]

@ccpony
You are having the different issue - not the one that was originally reported. You might want to open the separate issue for it.

[ccpony]

Thank you. I opened a new issue.