Files
Shaun Hamilton c2a11ad00d feat: add 'back/front end' in curriculum (#42596)
* chore: rename APIs and Microservices to include "Backend" (#42515)

* fix typo

* fix typo

* undo change

* Corrected grammar mistake

Corrected a grammar mistake by removing a comma.

* change APIs and Microservices cert title

* update title

* Change APIs and Microservices certi title

* Update translations.json

* update title

* feat(curriculum): rename apis and microservices cert

* rename folder structure

* rename certificate

* rename learn Markdown

* apis-and-microservices -> back-end-development-and-apis

* update backend meta

* update i18n langs and cypress test

Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>

* fix: add development to front-end libraries (#42512)

* fix: added-the-word-Development-to-front-end-libraries

* fix/added-the-word-Development-to-front-end-libraries

* fix/added-word-development-to-front-end-libraries-in-other-related-files

* fix/added-the-word-Development-to-front-end-and-all-related-files

* fix/removed-typos-from-last-commit-in-index.md

* fix/reverted-changes-that-i-made-to-dependecies

* fix/removed xvfg

* fix/reverted changes that i made to package.json

* remove unwanted changes

* front-end-development-libraries changes

* rename backend certSlug and README

* update i18n folder names and keys

* test: add legacy path redirect tests

This uses serve.json from the client-config repo, since we currently use
that in production

* fix: create public dir before moving serve.json

* fix: add missing script

* refactor: collect redirect tests

* test: convert to cy.location for stricter tests

* rename certificate folder to 00-certificates

* change crowdin config to recognise new certificates location

* allow translations to be used

Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com>

* add forwards slashes to path redirects

* fix cypress path tests again

* plese cypress

* fix: test different challenge

Okay so I literally have no idea why this one particular challenge
fails in Cypress Firefox ONLY. Tom and I paired and spun a full build
instance and confirmed in Firefox the page loads and redirects as
expected. Changing to another bootstrap challenge passes Cypress firefox
locally. Absolutely boggled by this.

AAAAAAAAAAAAAAA

* fix: separate the test

Okay apparently the test does not work unless we separate it into
a different `it` statement.

>:( >:( >:( >:(

Co-authored-by: Sujal Gupta <55016909+heysujal@users.noreply.github.com>
Co-authored-by: Noor Fakhry <65724923+NoorFakhry@users.noreply.github.com>
Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com>
2021-08-13 21:57:13 -05:00

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id, title, challengeType, forumTopicId, dashedName
id title challengeType forumTopicId dashedName
5a24c314108439a4d4036159 在數組中使用擴展運算符 6 301452 use-the-spread-operator-on-arrays

--description--

ES6 中有助於在 Redux 中強制執行狀態不變性的一個解決方案是擴展運算符:...。 擴展運算符具有很多的應用,其中一種非常適合通過一個已有的數組生成一個新數組。 這是相對較新的但常用的語法。 例如,如果你有一個數組 myArray 並寫:

let newArray = [...myArray];

newArray 現在是 myArray 的克隆。 兩個數組仍然分別存在於內存中。 如果你執行像 newArray.push(5) 這樣的變異, myArray 不會改變。 ... 有效將 myArray 中的值展開到一個新數組中。 要克隆數組,但在新數組中添加其他值,可以編寫 [...myArray, 'new value']。 這將返回一個由 myArray 中的值和字符串 new value(作爲最後一個值)組成的新數組。 擴展語法可以像這樣在數組組合中多次使用,但重要的是要注意它只是生成數組的淺拷貝副本。 也就是說,它只爲一維數組提供不可變的數組操作。

--instructions--

添加待辦事項時,使用 spread 運算符返回新的狀態副本。

--hints--

Redux store 應該在代碼編輯器中存在,並使用 ["Do not mutate state!"] 進行狀態初始化。

assert(
  (function () {
    const initialState = store.getState();
    return (
      Array.isArray(initialState) === true &&
      initialState[0] === 'Do not mutate state!'
    );
  })()
);

addToDoimmutableReducer 都應該是函數。

assert(typeof addToDo === 'function' && typeof immutableReducer === 'function');

在 Redux store 上 dispatch 一個類型爲 ADD_TO_DO 的 aciton應該添加一個 todo 項,並且不應該改變 state。

assert(
  (function () {
    const initialState = store.getState();
    const isFrozen = DeepFreeze(initialState);
    store.dispatch(addToDo('__TEST__TO__DO__'));
    const finalState = store.getState();
    const expectedState = ['Do not mutate state!', '__TEST__TO__DO__'];
    return isFrozen && DeepEqual(finalState, expectedState);
  })()
);

應使用擴展運算符返回新的 state。

(getUserInput) => assert(getUserInput('index').includes('...state'));

--seed--

--seed-contents--

const immutableReducer = (state = ['Do not mutate state!'], action) => {
  switch(action.type) {
    case 'ADD_TO_DO':
      // Don't mutate state here or the tests will fail
      return
    default:
      return state;
  }
};

const addToDo = (todo) => {
  return {
    type: 'ADD_TO_DO',
    todo
  }
}

const store = Redux.createStore(immutableReducer);

--solutions--

const immutableReducer = (state = ['Do not mutate state!'], action) => {
  switch(action.type) {
    case 'ADD_TO_DO':
      return [
        ...state,
        action.todo
      ];
    default:
      return state;
  }
};

const addToDo = (todo) => {
  return {
    type: 'ADD_TO_DO',
    todo
  }
}

const store = Redux.createStore(immutableReducer);