Question

尝试使用WebStorm时在Angular 8中编写单元测试。已调试并仍然收到错误消息，不允许构建单元测试。需要帮助。下面是我拥有的代码，然后提供了给出的错误消息。

import { TestBed, async } from '@angular/core/testing';
import { RouterTestingModule } from '@angular/router/testing';
import { AppComponent } from './app.component';
import { MatMenuModule} from '@angular/material/menu';
import {CUSTOM_ELEMENTS_SCHEMA} from '@angular/core';
import { SessionService } from './session.service';

describe('AppComponent', () => {
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [
        RouterTestingModule.withRoutes([]), MatMenuModule
      ],
      declarations: [
        AppComponent
      ],
      providers: [SessionService],
      schemas: [CUSTOM_ELEMENTS_SCHEMA]
    }).compileComponents();
  }));

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

  it(`should have as title 'apTime'`, () => {
    const fixture = TestBed.createComponent(AppComponent);
    const app = fixture.debugElement.componentInstance;
    expect(app.title).toEqual('apTime');
  });

  it('should render title', () => {
    const fixture = TestBed.createComponent(AppComponent);
    fixture.detectChanges();
    const compiled = fixture.debugElement.nativeElement;
    expect(compiled.querySelector('.content span').textContent).toContain('apTime app is running!');
  });
});

给出错误消息：

  StaticInjectorError(Platform: core)[AppComponent -> AmplifyService]: 
    NullInjectorError: No provider for AmplifyService!

error properties: Object({ ngTempTokenPath: null, ngTokenPath: [ 'AppComponent', Function ], ngDebugContext: DebugContext_({ view: Object({ def: Object({ factory: Function, nodeFlags: 33603585, rootNodeFlags: 33554433, nodeMatchedQueries: 0, flags: 0, nodes: [ Object({ nodeIndex: 0, parent: null, renderParent: null, bindingIndex: 0, outputIndex: 0, checkIndex: 0, flags: 33554433, childFlags: 49152, directChildFlags: 49152, childMatchedQueries: 0, matchedQueries: Object({  }), matchedQueryIds: 0, references: Object({  }), ngContentIndex: null, childCount: 1, bindings: [  ], bindingFlags: 0, outputs: [  ], element: Object({ ns: '', name: 'app-root', attrs: [  ], template: null, componentProvider: Object({ nodeIndex: 1, parent: <circular reference: Object>, renderParent: <circular reference: Object>, bindingIndex: 0, outputIndex: 0, checkIndex: 1, flags: 49152, childFlags: 0, directChildFlags: 0, childMatchedQueries: 0, matchedQueries: Object, matchedQueryIds: 0, references: Object, ngContentIndex: -1,  ...
    at <Jasmine>
    at NullInjector.get (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:855:1)
    at resolveToken (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:17514:1)
    at tryResolveToken (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:17440:1)
    at StaticInjector.get (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:17266:1)
    at resolveToken (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:17514:1)
    at tryResolveToken (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:17440:1)
    at StaticInjector.get (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:17266:1)
    at resolveNgModuleDep (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:30393:1)
    at NgModuleRef_.get (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:31578:1)
    at resolveDep (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/fesm2015/core.js:32143:1)

Answer 1

您必须在providers数组中添加AmplifyService。

beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [
        RouterTestingModule.withRoutes([]), MatMenuModule
      ],
      declarations: [
        AppComponent
      ],
      providers: [
        SessionService, 
        AmplifyService
      ],
      schemas: [CUSTOM_ELEMENTS_SCHEMA]
    }).compileComponents();
  }));

角单元测试-错误注入消息

1 个答案: