Unit testing 使用它对redux减速机进行单元测试'；它自己的初始状态

我有一个减速器，其默认初始状态定义如下：

const webReducer = (state = {
    fetched: false,
    data: {}
}, action) => {
    switch (action.type) {
        case "FETCH_DATA":
            state = {
                ...state,
                fetched: action.payload.fetched
            };

            state.data.push( action.payload.data );

            return state;
        break;
    }

    return state;
};

expect(
    webReducer( initialState, {
        type: "FETCH_DATA", 
        payload: object
    })
).toEqual( object );

当我运行测试以检查初始状态时，它通过了：

const initialState = {
    fetched: false,
    data: {}
};

it("Should have a default initial state", () => {
    expect( webReducer( undefined, {}) ).toEqual( initialState );
})

但是，当我尝试测试向状态添加数据时，它返回以下错误：

TypeError:state.data.push不是一个函数

这就是我做测试的方式：

const object = {
    fetched: true,
    data: {
        config: {size: 10}
    }
};

expect(
    webReducer( undefined, {
        type: "FETCH_DATA", 
        payload: object
    })
).toEqual( object );

如果我能顺利通过考试，为什么我现在会犯这个错误？我还尝试传递默认状态，如下所示：

const webReducer = (state = {
    fetched: false,
    data: {}
}, action) => {
    switch (action.type) {
        case "FETCH_DATA":
            state = {
                ...state,
                fetched: action.payload.fetched
            };

            state.data.push( action.payload.data );

            return state;
        break;
    }

    return state;
};

expect(
    webReducer( initialState, {
        type: "FETCH_DATA", 
        payload: object
    })
).toEqual( object );

---

但是我得到了同样的错误。

您将数据初始化为空对象，而该对象上没有推送功能。试着用下面的替换它，测试应该可以通过

state = {
fetched: false,
data: []

---

不得不做一些调整，以测试多个调度，但我得到了要点！谢谢你