typescript 运行 tslint 时，角度单元测试中的“未使用的表达式，需要赋值或函数调用”
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/44265207/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
'unused expression, expected an assignment or function call' in an angular unit test when running tslint
提问by bobbyrne01
Is there a way to fix this error without having to place an ignore in the file?
有没有办法解决这个错误而不必在文件中放置一个忽略？
Error when running command:
运行命令时出错：
./node_modules/tslint/bin/tslint -p src/tsconfig.json --type-check src/app/app.component.spec.ts
[21, 5]: unused expression, expected an assignment or function call
Test:
测试：
let chai = require('chai');
let expect = chai.expect;
import { AppComponent } from './app.component';
import { ComponentFixture, TestBed } from '@angular/core/testing';
describe('AppComponent', function() {
let testAppComponent: AppComponent;
let fixture: ComponentFixture<AppComponent>;
beforeEach(() => {
TestBed.configureTestingModule({
declarations: [AppComponent]
});
fixture = TestBed.createComponent(AppComponent);
testAppComponent = fixture.componentInstance;
});
it('should create the correct component', () => {
expect(testAppComponent instanceof AppComponent).to.be.true;
});
});
采纳答案by Duncan
Did you perhaps mean this:
你可能是这个意思：
expect(testAppComponent instanceof AppComponent).toBe(true);
The expression you have there just accesses a bunch of properties, you need some kind of function call for it to actually do anything.
您在那里拥有的表达式只是访问一堆属性，您需要某种函数调用才能真正执行任何操作。
