No provider for MatSnackBar error when trying to run "ng test"

You should import the module instead of the component.

import { MatSnackBar, MatSnackBarModule } from '@angular/material';....describe('BranchNameCellComponent', () => {  let component: BranchNameCellComponent;  let fixture: ComponentFixture<BranchNameCellComponent>;      beforeEach(async(() => {    TestBed.configureTestingModule({      declarations: [ BranchNameCellComponent ],      imports: [ HttpClientTestingModule, ReactiveFormsModule, MatSnackBarModule ],      schemas: [ NO_ERRORS_SCHEMA ]    }).compileComponents();  }));      it('should create', () => {    fixture = TestBed.createComponent(BranchNameCellComponent);    component = fixture.componentInstance;    expect(component).toBeTruthy();  });});

For the issue related to the timeout, try adding this to your karma config file:

captureTimeout: 210000,browserDisconnectTolerance: 3, browserDisconnectTimeout : 210000,browserNoActivityTimeout : 210000,

I was facing this error when in my angular app, I was navigating to some module which was lazy loaded. This module was importing MatSnackBarModule but I needed to import MatSnackBarModule in app.module.ts file as well

This has happened to me recently and I decided like this::

Include file aap.module.ts

import { MatSnackBarModule } from '@angular/material/snack-bar';......imports: [    ...    MatSnackBarModule  ]...

On file component or service:

import { MatSnackBar } from '@angular/material/snack-bar';......constructor(private snackBar: MatSnackBar) { }...