来自redux saga并带来承诺回报

Question

我无法让yield使用promises代码。当我使用yield函数直接解析返回值时，它一切正常。但是当我使用带有代理函数的yield时，它会返回另一个带有promise的函数 - 它会停止工作。

怎么了？这是示例代码：

const fetchRequest = (payload) => {
    return new API.user().fetch(payload);
};

const fetchRequestFull = (payload) => {
    return new Promise((resolve, reject) => {
        if (payload) resolve({'response'});
    });
};

function* fetchUser(action) {
    try {
        const userData = yield call(new API.user().fetch, action.payload); // doesnt work
        const userDataOther = yield call(fetchRequest, action.payload); // doesnt work
        const userDataYetAnother = yield call(fetchRequestFull, action.payload); // works
        // ...
    } catch (e) {
        yield put({
            type: LOGOUT,
        });
    }
}