ng build --prod Cannot determine the module for class X! Add ThreadListTabsComponent to the NgModule to fix it

Question

I'm trying to build my Angular 5 app, and I'm getting the error:

Cannot determine the module for class ThreadListTabsComponent in /home/brightwater/Differ/src/app/thread-lists/thread-lists.component.ts! Add ThreadListTabsComponent to the NgModule to fix it.

This is confusing because I'm importing the offending component in the module:

thread-lists.module.ts:

import { OtherModules } from './modules-everywhere';
import { NgModule }      from '@angular/core'

import { SomeOtherComponents }  from './other-components.component';
import { ThreadListTabsComponent } from './thread-list-tabs.component';

@NgModule({
  imports: 
  [ 
    OtherModules
  ],
  declarations: [
    OtherComponents,
    ThreadListTabsComponent
  ],
  exports: [
    OtherComponents,
    ThreadListTabsComponent
  ],
  providers: [ ThreadListsService ]
})


export class ThreadListsModule { }

Here's the component:

thread-list-tabs.component.ts

import { Component } from '@angular/core';
import { Observable } from 'rxjs/Observable';
import { Router }   from '@angular/router';
import { ThreadListsService }   from './thread-lists.service';

@Component({
  moduleId: module.id,
  selector: 'thread-list-tabs',
  templateUrl: 'thread-list-tabs.component.html',
  styleUrls: ['thread-list-tabs.component.css']
})


export class ThreadListTabsComponent {

  // Stuff this component does

}

app.module.ts

import { NgModule } from '@angular/core'
import { ThreadListsModule } from './thread-lists/thread-lists.module'
import { OtherModules } from './other.modules'
import { AppComponent } from './app.component'

@NgModule({
  imports: [    
    OtherModules, 
    ThreadListsModule
  ],
  declarations: [ 
    AppComponent
  ],
  providers: [ SomeService ],
  bootstrap: [ AppComponent ]
})

export class AppModule { }

Is there something I'm missing?

Solution

This looks like a filename casing problem, see the issue described on angular git repo (https://github.com/angular/angular-cli/issues/10732)

Comments

[Daniel W Strimpel]

That error is complaining about a class in the thread-lists.component.ts file but you have the thread-list-tabs.component.ts file shown above. Is it possible that you are looking in the wrong file for the problem class?

[J. Adam Connor]

Good eye! thread-lists and thread-list-tabs a duplicate components. This fixed the issue. You're welcome to post the answer if you like and I'll accept--though I wonder how helpful such answers are, as they're so specific and related to my own blindness... Thank you, though.