angular - Angular 2+ - 如何模拟用于环境变量的常量类

问题描述

我想知道是否有人可以在这个主题上帮助我，我正在输入一些关于某些功能的单元测试，这些功能取决于目前正在运行的环境。

这是我要创建单元测试的组件的源代码：

import { Component, OnInit } from '@angular/core';

// DEV environment
import { environment } from '@env/environment';
// PROD environment
// import { environment } from '@env/environment.prod';
import { Logger } from '@app/core/logger/logger.service';
import { I18nService } from '@app/core/language/i18n.service';

let log: Logger;

@Component({
  selector: 'app-root',
   templateUrl: './app.component.html',
   styleUrls: ['./app.component.scss'],
   providers: [I18nService]
 })

export class AppComponent implements OnInit {

  constructor(private i18nService: I18nService) {
     log  = new Logger('X');
  }

  ngOnInit() {
    // Setup logger
    if (environment.isProduction) {
        Logger.enableProductionMode();
    }

    log.debug('init');

    // Setup translations
    this.i18nService.init(environment.defaultLanguage, environment.supportedLanguages);
  }

这是单元测试：

 import * as environmentDEV from '@env/environment';
 import * as environmentPRO from '@env/environment.prod';
 ...

 let component: AppComponent;
 let fixture: ComponentFixture<AppComponent>;

 // Spies declarations
 let spy_initI8nServiceMethod: jasmine.Spy;
 let spy_debugLoggerAttr: jasmine.Spy;
 let spy_enableProductionModeLoggerMethod: jasmine.Spy;

 describe('AppComponent', () => {
       beforeEach(async(() => {
        TestBed.configureTestingModule({
          imports: [TranslateModule.forRoot()],
          declarations: [AppComponent],
          providers: [I18nService]
        });
        TestBed.compileComponents();
        fixture = TestBed.createComponent(AppComponent);
        component = fixture.debugElement.componentInstance;
       }));

       beforeEach(inject([I18nService],
                        (_i18nService: I18nService) => {

        i18nService = _i18nService;

        // Create spies
        // Spies
        spy_initI8nServiceMethod = spyOn(I18nService.prototype, 'init');
        spy_debugLoggerAttr = spyOn(Logger.prototype, 'debug');
        spy_enableProductionModeLoggerMethod = spyOn(Logger, 'enableProductionMode');
       }));

       it('should component init on PRO environment',
           async(() => {

        spyOn(environment, 'isProduction').and.returnValue(environmentPRO.environment.isProduction);
        spyOn(environment, 'defaultLanguage').and.returnValue(environmentPRO.environment.defaultLanguage);
        spyOn(environment, 'supportedLanguages').and.returnValue(environmentPRO.environment.supportedLanguages);

        component.ngOnInit();

        expect(spy_enableProductionModeLoggerMethod).toHaveBeenCalledBefore(spy_debugLoggerAttr);
        expect(spy_debugLoggerAttr).toHaveBeenCalledBefore(spy_initI8nServiceMethod);
        expect(spy_initI8nServiceMethod).toHaveBeenCalledWith(environmentPRO.environment.defaultLanguage,
                                                              environmentPRO.environment.supportedLanguages);
       }));
 });

我的问题是我无法强制常量环境返回某些值，我都尝试过 spyOn 和 spyOnAttribute ，结果相同。这里有什么问题？我应该尝试另一种方法吗？

标签： angulartypescriptjasminekarma-jasmineconstants

angular - Angular 2+ - 如何模拟用于环境变量的常量类

问题描述

解决方案

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