Question

这是一个有趣的问题：我试图测试使用Ionic BarcodeScanner的服务。我有一个基于ionic unit-testing repository的回购，以便尝试测试。我通过spyOn(..).and.callFake(..)

嘲笑BarcodeScanner.scan方法

问题：当我从组件调用扫描方法时，它可以正常工作。当我在服务中执行完全相同的操作时，它会抛出超时。

组件测试代码：

it("should be able to set a spy on the scanner and test the component", done => {
    const testBC = "123456";
    const spy = spyOn(TestBed.get(BarcodeScanner), "scan");
    spy.and.callFake(() => {
        return new Promise((resolve, reject) => {
            resolve(testBC);
        })
    });

        component.testScanner().then(res => {
            expect(res).toBe(testBC);
            done();
        }, reason => {
            expect(true).toBe(false);
            done();
        })
});

服务测试代码：

it("should be able to set a spy on the scanner and test the service", done => {
    const testBC = "123456";
    const spy = spyOn(TestBed.get(BarcodeScanner), "scan");
    spy.and.callFake(() => {
        return new Promise((resolve, reject) => {
            resolve(testBC);
        })
    });

    inject([TestService], (service) => {
        service.testScanner().then(res => {
            expect(res).not.toBe(testBC);
            done()
        }, reason => {
            expect(true).toBe(false);
            done();
        })
    })
});

Angular 2中是否有任何已知的测试服务问题？任何帮助表示赞赏！

Answer 1

问题是没有调用注入函数。

该服务的测试代码现在如下所示：

it("should be able to set a spy on the scanner and test the service", done => {
    const testBC = "123456";
    const spy = spyOn(TestBed.get(BarcodeScanner), "scan");
    spy.and.callFake(() => {
        return new Promise((resolve, reject) => {
            resolve(testBC);
        })
    });

    inject([TestService], (service) => {
        service.testScanner().then(res => {
            expect(res).not.toBe(testBC);
            done()
        }, reason => {
            expect(true).toBe(false);
            done(); 
        })
    })(); //<-- do not forget these braces!!
});

在Angular 2服务中测试异步（Promise）方法

1 个答案: