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id	title	challengeType	isRequired	videoUrl	localeTitle
5a24c314108439a4d4036143	Extract State Logic to Redux	6	false		将状态逻辑提取到Redux

Description

现在您已完成React组件，您需要将其在其state本地执行的逻辑移动到Redux中。这是将简单的React应用程序连接到Redux的第一步。您的应用程序的唯一功能是将用户的新消息添加到无序列表中。该示例很简单，以演示React和Redux如何协同工作。

Instructions

首先，定义一个动作类型'ADD'并将其设置为const ADD 。接下来，定义一个动作创建器addMessage() ，它创建添加消息的动作。您需要将message给此操作创建者，并在返回的action包含该消息。然后创建一个名为messageReducer()的reducer来处理消息的状态。初始状态应该等于空数组。此reducer应向状态中保存的消息数组添加消息，或返回当前状态。最后，创建Redux存储并将其传递给reducer。

Tests

tests:
  - text: const <code>ADD</code>应该存在并保持一个等于字符串<code>ADD</code>的值
    testString: 'assert(ADD === "ADD", "The const <code>ADD</code> should exist and hold a value equal to the string <code>ADD</code>");'
  - text: 动作创建者<code>addMessage</code>应返回<code>type</code>等于<code>ADD</code>的对象，并且消息等于传入的消息。
    testString: 'assert((function() { const addAction = addMessage("__TEST__MESSAGE__"); return addAction.type === ADD && addAction.message === "__TEST__MESSAGE__"; })(), "The action creator <code>addMessage</code> should return an object with <code>type</code> equal to <code>ADD</code> and message equal to the message that is passed in.");'
  - text: <code>messageReducer</code>应该是一个函数。
    testString: 'assert(typeof messageReducer === "function", "<code>messageReducer</code> should be a function.");'
  - text: 存储应该存在并且初始状态设置为空数组。
    testString: 'assert((function() { const initialState = store.getState(); return typeof store === "object" && initialState.length === 0; })(), "The store should exist and have an initial state set to an empty array.");'
  - text: 对商店调度<code>addMessage</code>应该<code>addMessage</code>向状态中保存的消息数组添加新消息。
    testString: 'assert((function() { const initialState = store.getState(); const isFrozen = DeepFreeze(initialState); store.dispatch(addMessage("__A__TEST__MESSAGE")); const addState = store.getState(); return (isFrozen && addState[0] === "__A__TEST__MESSAGE"); })(), "Dispatching <code>addMessage</code> against the store should immutably add a new message to the array of messages held in state.");'
  - text: 如果使用任何其他操作调用， <code>messageReducer</code>应返回当前状态。
    testString: 'assert((function() { const addState = store.getState(); store.dispatch({type: "FAKE_ACTION"}); const testState = store.getState(); return (addState === testState); })(), "The <code>messageReducer</code> should return the current state if called with any other actions.");'

Challenge Seed

// define ADD, addMessage(), messageReducer(), and store here:

Solution

// solution required

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