在角度指令单元测试中注入服务

Question

I'm trying to first fix the basic unit test that cli wrote for me. I'm new to unit testing so here's the code

import { MyDirective } from './my.directive';

describe('MyDirective', () => {
  it('should create an instance', () => {
    const directive = new MyDirective(); // it throws error here
    expect(directive).toBeTruthy();
  });
});

I need to inject ElementRef inside MyDirective

Answer 1

I've wasted a couple of hours during my problem solving. Here the answer. For example, we need to inject ElementRef and NgControl:

import { inject } from '@angular/core/testing';
import { ElementRef } from '@angular/core';
import { NgControl } from '@angular/forms'
import { MyDirective } from './my.directive';

describe('MyDirective', () => {
  it('should create an instance', inject([ElementRef, NgControl], (elementRef: ElementRef, ngControl: NgControl) => {
      const directive = new MyDirective(elementRef, ngControl);

      expect(directive).toBeTruthy();
    }));
  });
});