Testing ngModel

import { BrowserModule } from '@angular/platform-browser';
import { CommonModule } from '@angular/common';
import { FormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';

import { Component, DebugElement } from '@angular/core';
import { dispatchEvent } from "@angular/platform-browser/testing/browser_util";
import { TestBed, ComponentFixture} from '@angular/core/testing';
import {By} from "@angular/platform-browser";

import { MyComponentModule } from 'ng2-my-component';
import { MyComponent } from './my-component';

describe('MyComponent:',()=> {

  const template = `
    <div>
       <my-component type="text" [(ngModel)]="value" name="TestName" size="9" min="3" max="8" placeholder="testPlaceholder" disabled=false required=false></my-component>
    </div>
  `;

  let fixture:any;
  let element:any; 
  let context:any;
 
  beforeEach(() => {

      TestBed.configureTestingModule({
          declarations: [InlineEditorComponent],
          imports: [
            FormsModule,
            InlineEditorModule]
      });      
      fixture = TestBed.overrideComponent(InlineEditorComponent, {
      set: {
        selector:"inline-editor-test",
        template: template
      }})
      .createComponent(InlineEditorComponent);
      context = fixture.componentInstance;
      fixture.detectChanges();
  });

  it('should change value of the component', () => {
        let input = fixture.nativeElement.querySelector("input");
        input.value = "Username";
        dispatchEvent(input, 'input');
        fixture.detectChanges();

        fixture.whenStable().then(() => {
            //this button dispatch event for save the text in component.value
            fixture.nativeElement.querySelectorAll('button')[0].click();
            expect(context.value).toBe("Username");
        });
    });
});