使用Dart模拟HTTP响应

我一直在研究新的API包装器,并且不希望每次运行单元测试时都调用API.因此,作为描述在这里,我嘲笑它.

我最初认为我嘲笑它的方式有问题,但似乎问题出在其他地方.

我想要完成的事情非常简单.当我的单元测试运行时,我想返回一个值,好像我已经出去从我正在集成的外部API获取信息.

我使用http.Client作为可选参数初始化我的类,所以我可以在单元测试运行时将其传入:

SampleClass(String arg1, String arg2, [http.Client httpClient = null]) {
    this._arg1 = arg1;
    this._arg2 = arg2;
    _httpClient = (httpClient == null) ? http.Request : httpClient;
}

Future apiRequest(String resource, [Map body]) {
    var url = buildBaseUrl(resource).toString();
    var request = new http.Request('POST', Uri.parse(url));
    request.bodyFields = body;
    return this._httpClient.send(request).then((response) => response.stream.bytesToString().then((value) => value.toString()));
}

class HttpClientMock extends Mock implements http.Client {
  noSuchMethod(i) => super.noSuchMethod(i);
}

class HttpResponseMock extends Mock implements http.Response {
    noSuchMethod(i) => super.noSuchMethod(i);
}

test("Send SMS errors with wrong account", () {
    var mockHttpClient = new HttpClientMock()
                             ..when(callsTo('send')).alwaysReturn(message401);
    var sample = new SampleClass(_arg1, _arg2, mockHttpClient);
    future = sample.apiRequest(...parameters here...).then((value) => value.toString());
    expect(future.then((value) => JSON.decode(value)), completion(equals(JSON.decode(message401))));
});