Testing a click from an Angular Attribute Directive

I'm having trouble creating a unit test for an Angular Attribute Directive that I've written. The directive is called TrackClickDirective, and I'm trying to test the following.

• When an element which has this directive attached is clicked, it should call a specific method on the directive.

I suspect it's a problem with my unit test configuration.

Please see my implementation on StackBlitz, where you can see the test running:

https://stackblitz.com/edit/angular-pkcme8

Here is my unit test code - track-click.directive.spec.ts:

import { Component, ElementRef, DebugElement } from '@angular/core';
import { ComponentFixture, TestBed } from '@angular/core/testing';
import { By } from "@angular/platform-browser";
import { TrackClickDirective } from './track-click.directive';
import { Analytics} from './analytics.service';

class MockAnalytics {
  eventTrack() {}
};
class MockElementRef {
}

@Component({
  template: '<button appTrackClick>Test</button>'
})
export class TestButtonWithoutNameComponent { }

describe('TrackClickDirective', () => {

  let component: TestButtonWithoutNameComponent;
  let fixture: ComponentFixture<TestButtonWithoutNameComponent>;
  let directive: TrackClickDirective;
  let inputEl: DebugElement;
  let spy: any;

  beforeEach(() => {
    TestBed.configureTestingModule({
      declarations: [
        TestButtonWithoutNameComponent
      ],
      providers: [
        TrackClickDirective,
        { provide: Analytics, useClass: MockAnalytics },
        { provide: ElementRef, useClass: MockElementRef }
      ]
    });
    fixture = TestBed.createComponent(TestButtonWithoutNameComponent);
    component = fixture.componentInstance;
    directive = TestBed.get(TrackClickDirective);
    inputEl = fixture.debugElement.query(By.css('button'));
  });

  it('should call the trackClick methoe when the button is clicked', () => {
    spy = spyOn(directive, 'trackClick');
    inputEl.triggerEventHandler('click', null);
    fixture.detectChanges();
    expect(directive.trackClick).toHaveBeenCalled();
  });
});

What am I doing wrong here? When I run the unit test, I get the following:

FAILED TESTS:
  TrackClickDirective
    ✖ should call the trackClick method when the button is clicked
      HeadlessChrome 72.0.3626 (Mac OS X 10.14.0)
    Expected spy trackClick to have been called.

from Testing a click from an Angular Attribute Directive