angular-testing.md

Angular Testing

SpyOn

// Should call
it('Should call myFunc', () => {
  const spiedFunction = spyOn<any>(component, 'myFunc');
  component.myMethod();
  expect(spiedFunction).toHaveBeenCalled();
});

// Should not call
it('Should not call myFunc', () => {
  const spiedFunction = spyOn<any>(component, 'myFunc');
  component.myMethod();
  expect(spiedFunction).not.toHaveBeenCalled();
});

External function

import * as dateHelper from './date.helper';

it('Should call dayIsValid', () => {
  const spiedFunction = spyOn<any>(
    dateHelper,
    'isValid'
  ).and.returnValue({});
  component.myMethod();
  expect(spiedFunction).toHaveBeenCalled();
});

Private method

it('Should call myFunc', () => {
  const spiedFunction = spyOn<any>(component, 'myFunc');
  component.myMethod();
  expect(spiedFunction).toHaveBeenCalled();
});

Tools

• Spectator
• BackstopJS
• Jasmine Marbles - Observable testing

Articles

• Angular Testing Cheatsheet