Angular 使用模拟结构指令测试组件失败

Question

我正在尝试在组件测试中模拟结构指令，但出现错误。

以下测试失败并显示消息：

Property binding appSome not used by any directive on an embedded template. Make sure that the property name is spelled correctly and all directives are listed in the "@NgModule.declarations". ("[ERROR ->]TEST

我正在用 app.component.spec.ts 中定义的 SomeMockDirective 模拟结构指令 SomeDirective。 测试失败。

如果我切换声明使其包含 SomeDirective - 测试通过。

我想知道为什么我不能使用模拟版本。

模板：

<h1 *appSome="true">TEST</h1>

指令（生产类型:)）：

@Directive({
  selector: '[appSome]'
})
export class SomeDirective implements OnDestroy {
  show: boolean;
  ...
}

测试：

import { TestBed, async } from '@angular/core/testing';
import { AppComponent } from './app.component';
import { Directive, NO_ERRORS_SCHEMA } from '@angular/core';

@Directive({
  selector: '[appSome]'
})
export class SomeMockDirective {}

describe('AppComponent', () => {
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [AppComponent, SomeMockDirective], // test is failing, switch the directive to SomeDirective and it passes
      schemas: [NO_ERRORS_SCHEMA]
    }).compileComponents();
  }));

  it('should create the app', () => {
    const fixture = TestBed.createComponent(AppComponent);
    const app = fixture.debugElement.componentInstance;
    expect(app).toBeTruthy();
  });
});

复制回购： https://github.com/felikf/angular-test-directive

git clone https://github.com/felikf/angular-test-directive.git 
npm i
ng test

我的问题是，为什么模拟版本不起作用，即使 providers: [] 中提供了模拟版本并且指令具有相同的选择器。

Answer 1

模拟版本不起作用，因为您尚未定义 appSome 输入属性:

@Directive({
  selector: '[appSome]'
})
export class SomeMockDirective {
  @Input() appSome;  <================= add this
}

Angular 使用模拟结构指令测试组件失败

Angular testing component with mocked structural directive fails

angular

angular-directive

angular-test