我第一次运行“ng test”并得到这个错误:
src/app/_directives/head-title.directive.spec.ts(5,23) 中的错误:错误 TS2554:需要 2 个参数,但得到 0 个参数。
由于 spec.ts 文件是由 Angular 自动生成的,我不知道该怎么做......
这是我的指令:
import { Directive, ElementRef, AfterContentInit } from '@angular/core';
import { Title } from '@angular/platform-browser';
@Directive({
selector: '[edHeadTitle]'
})
export class HeadTitleDirective implements AfterContentInit{
constructor(private el: ElementRef,private titleService: Title) {}
ngAfterContentInit(){
this.titleService.setTitle(this.el.nativeElement.innerHTML);
}
}
这是相应的 spec.ts:
import { HeadTitleDirective } from './head-title.directive';
describe('HeadTitleDirective', () => {
it('should create an instance', () => {
const directive = new HeadTitleDirective();
expect(directive).toBeTruthy();
});
});
显然有问题的部分是“new HeadTitleDirective()”……我想应该有一些参数,但是哪些参数以及如何?
来自 package.json 的版本信息:
"devDependencies": {
"@angular-devkit/build-angular": "~0.6.8",
"@angular/cli": "~6.0.8",
"@angular/compiler-cli": "^6.0.6",
"@angular/language-service": "^6.0.6",
"@types/jasmine": "~2.8.6",
"@types/jasminewd2": "~2.0.3",
"@types/node": "~8.9.4",
"codelyzer": "~4.2.1",
"jasmine-core": "~2.99.1",
"jasmine-spec-reporter": "~4.2.1",
"karma": "~1.7.1",
"karma-chrome-launcher": "~2.2.0",
"karma-coverage-istanbul-reporter": "~2.0.0",
"karma-jasmine": "~1.1.1",
"karma-jasmine-html-reporter": "^0.2.2",
"protractor": "~5.3.0",
"ts-node": "~5.0.1",
"tslint": "~5.9.1",
"typescript": "~2.7.2"
}
最佳答案
这是基本编码。
这是你的类(class)签名:
constructor(private el: ElementRef,private titleService: Title) {}
创建它的方法如下:
const directive = new HeadTitleDirective();
你在那里使用问题吗?
要解决它,只需创建您的依赖项的模拟。
let elRefMock = {
nativeElement: document.createElement('div')
};
let serviceMock = {
setTitle: (title: string) => null
};
const directive = new HeadTitleDirective(elRefMock, serviceMock);
关于angular - *.directive.spec.ts 中的错误 TS2554,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/51493938/