├── .vscode
    ├── settings.json
    ├── extensions.json
    └── launch.json
├── src
    ├── react-app-env.d.ts
    ├── App.test.tsx
    ├── index.css
    ├── index.tsx
    ├── App.css
    ├── App.tsx
    ├── logo.svg
    └── serviceWorker.ts
├── public
    ├── robots.txt
    ├── favicon.ico
    ├── logo192.png
    ├── logo512.png
    ├── manifest.json
    └── index.html
├── .gitignore
├── tsconfig.json
├── package.json
└── README.md


/.vscode/settings.json:
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1 | {
2 |   "prettier.printWidth": 120
3 | }


--------------------------------------------------------------------------------
/src/react-app-env.d.ts:
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1 | /// <reference types="react-scripts" />
2 | 


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/public/robots.txt:
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1 | # https://www.robotstxt.org/robotstxt.html
2 | User-agent: *
3 | 


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/public/favicon.ico:
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https://raw.githubusercontent.com/codetalks-new/learn-react/HEAD/public/favicon.ico


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/public/logo192.png:
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https://raw.githubusercontent.com/codetalks-new/learn-react/HEAD/public/logo192.png


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/public/logo512.png:
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https://raw.githubusercontent.com/codetalks-new/learn-react/HEAD/public/logo512.png


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/src/App.test.tsx:
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 1 | import React from 'react';
 2 | import ReactDOM from 'react-dom';
 3 | import App from './App';
 4 | 
 5 | it('renders without crashing', () => {
 6 |   const div = document.createElement('div');
 7 |   ReactDOM.render(<App />, div);
 8 |   ReactDOM.unmountComponentAtNode(div);
 9 | });
10 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
 1 | # See https://help.github.com/articles/ignoring-files/ for more about ignoring files.
 2 | 
 3 | # dependencies
 4 | /node_modules
 5 | /.pnp
 6 | .pnp.js
 7 | 
 8 | # testing
 9 | /coverage
10 | 
11 | # production
12 | /build
13 | 
14 | # misc
15 | .DS_Store
16 | .env.local
17 | .env.development.local
18 | .env.test.local
19 | .env.production.local
20 | 
21 | npm-debug.log*
22 | yarn-debug.log*
23 | yarn-error.log*
24 | 


--------------------------------------------------------------------------------
/src/index.css:
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 1 | body {
 2 |   margin: 0;
 3 |   font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
 4 |     'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
 5 |     sans-serif;
 6 |   -webkit-font-smoothing: antialiased;
 7 |   -moz-osx-font-smoothing: grayscale;
 8 | }
 9 | 
10 | code {
11 |   font-family: source-code-pro, Menlo, Monaco, Consolas, 'Courier New',
12 |     monospace;
13 | }
14 | 


--------------------------------------------------------------------------------
/src/index.tsx:
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 1 | import React from 'react';
 2 | import ReactDOM from 'react-dom';
 3 | import './index.css';
 4 | import App from './App';
 5 | import * as serviceWorker from './serviceWorker';
 6 | 
 7 | ReactDOM.render(<App />, document.getElementById('root'));
 8 | 
 9 | // If you want your app to work offline and load faster, you can change
10 | // unregister() to register() below. Note this comes with some pitfalls.
11 | // Learn more about service workers: https://bit.ly/CRA-PWA
12 | serviceWorker.unregister();
13 | 


--------------------------------------------------------------------------------
/.vscode/extensions.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   // See http://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
 3 |   // Extension identifier format: ${publisher}.${name}. Example: vscode.csharp
 4 | 
 5 |   // List of extensions which should be recommended for users of this workspace.
 6 |   "recommendations": ["orta.vscode-jest", "msjsdiag.debugger-for-chrome", "esbenp.prettier-vscode"],
 7 |   // List of extensions recommended by VS Code that should not be recommended for users of this workspace.
 8 |   "unwantedRecommendations": []
 9 | }
10 | 


--------------------------------------------------------------------------------
/tsconfig.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "compilerOptions": {
 3 |     "target": "es5",
 4 |     "lib": [
 5 |       "dom",
 6 |       "dom.iterable",
 7 |       "esnext"
 8 |     ],
 9 |     "allowJs": true,
10 |     "skipLibCheck": true,
11 |     "esModuleInterop": true,
12 |     "allowSyntheticDefaultImports": true,
13 |     "strict": true,
14 |     "forceConsistentCasingInFileNames": true,
15 |     "module": "esnext",
16 |     "moduleResolution": "node",
17 |     "resolveJsonModule": true,
18 |     "isolatedModules": true,
19 |     "noEmit": true,
20 |     "jsx": "react"
21 |   },
22 |   "include": [
23 |     "src"
24 |   ]
25 | }
26 | 


--------------------------------------------------------------------------------
/public/manifest.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "short_name": "React App",
 3 |   "name": "Create React App Sample",
 4 |   "icons": [
 5 |     {
 6 |       "src": "favicon.ico",
 7 |       "sizes": "64x64 32x32 24x24 16x16",
 8 |       "type": "image/x-icon"
 9 |     },
10 |     {
11 |       "src": "logo192.png",
12 |       "type": "image/png",
13 |       "sizes": "192x192"
14 |     },
15 |     {
16 |       "src": "logo512.png",
17 |       "type": "image/png",
18 |       "sizes": "512x512"
19 |     }	 
20 |   ],
21 |   "start_url": ".",
22 |   "display": "standalone",
23 |   "theme_color": "#000000",
24 |   "background_color": "#ffffff"
25 | }
26 | 


--------------------------------------------------------------------------------
/src/App.css:
--------------------------------------------------------------------------------
 1 | .App {
 2 |   text-align: center;
 3 | }
 4 | 
 5 | .App-logo {
 6 |   animation: App-logo-spin infinite 10s linear;
 7 |   height: 40vmin;
 8 |   pointer-events: none;
 9 | }
10 | 
11 | .App-header {
12 |   background-color: #282c34;
13 |   min-height: 100vh;
14 |   display: flex;
15 |   flex-direction: column;
16 |   align-items: center;
17 |   justify-content: center;
18 |   font-size: calc(10px + 2vmin);
19 |   color: white;
20 | }
21 | 
22 | .App-link {
23 |   color: #61dafb;
24 | }
25 | 
26 | @keyframes App-logo-spin {
27 |   from {
28 |     transform: rotate(0deg);
29 |   }
30 |   to {
31 |     transform: rotate(360deg);
32 |   }
33 | }
34 | 


--------------------------------------------------------------------------------
/src/App.tsx:
--------------------------------------------------------------------------------
 1 | import React from "react";
 2 | import logo from "./logo.svg";
 3 | import "./App.css";
 4 | 
 5 | function currentTime() {
 6 |   return new Date().toISOString();
 7 | }
 8 | 
 9 | const App: React.FC = () => {
10 |   return (
11 |     <div className="App">
12 |       <header className="App-header">
13 |         <p>当前时间: {currentTime()} </p>
14 |         <img src={logo} className="App-logo" alt="logo" />
15 |         <p>
16 |           Edit <code>src/App.tsx</code> and save to reload.
17 |         </p>
18 |         <a
19 |           className="App-link"
20 |           href="https://reactjs.org"
21 |           target="_blank"
22 |           rel="noopener noreferrer"
23 |         >
24 |           Learn React
25 |         </a>
26 |       </header>
27 |     </div>
28 |   );
29 | };
30 | 
31 | export default App;
32 | 


--------------------------------------------------------------------------------
/package.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "name": "learn-react",
 3 |   "version": "0.1.0",
 4 |   "private": true,
 5 |   "dependencies": {
 6 |     "@types/jest": "24.0.18",
 7 |     "@types/node": "12.7.2",
 8 |     "@types/react": "16.9.2",
 9 |     "@types/react-dom": "16.9.0",
10 |     "react": "^16.9.0",
11 |     "react-dom": "^16.9.0",
12 |     "react-scripts": "3.1.1",
13 |     "typescript": "3.6.2"
14 |   },
15 |   "scripts": {
16 |     "start": "react-scripts start",
17 |     "build": "react-scripts build",
18 |     "test": "react-scripts test",
19 |     "test_node": "react-scripts test --env=node",
20 |     "test:debug": "react-scripts --inspect-brk test --runInBand --no-cache",
21 |     "eject": "react-scripts eject"
22 |   },
23 |   "eslintConfig": {
24 |     "extends": "react-app"
25 |   },
26 |   "browserslist": {
27 |     "production": [
28 |       ">0.2%",
29 |       "not dead",
30 |       "not op_mini all"
31 |     ],
32 |     "development": [
33 |       "last 1 chrome version",
34 |       "last 1 firefox version",
35 |       "last 1 safari version"
36 |     ]
37 |   }
38 | }
39 | 


--------------------------------------------------------------------------------
/.vscode/launch.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "version": "0.2.0",
 3 |   "configurations": [
 4 |     {
 5 |       "type": "node",
 6 |       "name": "vscode-jest-tests",
 7 |       "request": "launch",
 8 |       "program": "${workspaceFolder}/node_modules/jest/bin/jest",
 9 |       "args": ["--runInBand"],
10 |       "cwd": "${workspaceFolder}",
11 |       "console": "integratedTerminal",
12 |       "internalConsoleOptions": "neverOpen",
13 |       "disableOptimisticBPs": true
14 |     },
15 |     {
16 |       "name": "Chrome",
17 |       "type": "chrome",
18 |       "request": "launch",
19 |       "url": "http://localhost:3000",
20 |       "webRoot": "${workspaceFolder}/src",
21 |       "sourceMapPathOverrides": {
22 |         "webpack:///src/*": "${webRoot}/*"
23 |       }
24 |     },
25 |     {
26 |       "name": "Debug CRA Tests",
27 |       "type": "node",
28 |       "request": "launch",
29 |       "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/react-scripts",
30 |       "args": ["test", "--runInBand", "--no-cache", "--watchAll=false"],
31 |       "cwd": "${workspaceRoot}",
32 |       "protocol": "inspector",
33 |       "console": "integratedTerminal",
34 |       "internalConsoleOptions": "neverOpen",
35 |       "env": {
36 |         "CI": "true"
37 |       },
38 |       "disableOptimisticBPs": true
39 |     }
40 |   ]
41 | }
42 | 


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/public/index.html:
--------------------------------------------------------------------------------
 1 | <!DOCTYPE html>
 2 | <html lang="en">
 3 |   <head>
 4 |     <meta charset="utf-8" />
 5 |     <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico" />
 6 |     <meta name="viewport" content="width=device-width, initial-scale=1" />
 7 |     <meta name="theme-color" content="#000000" />
 8 |     <meta
 9 |       name="description"
10 |       content="Web site created using create-react-app"
11 |     />
12 |     <link rel="apple-touch-icon" href="logo192.png" />
13 |     <!--
14 |       manifest.json provides metadata used when your web app is installed on a
15 |       user's mobile device or desktop. See https://developers.google.com/web/fundamentals/web-app-manifest/
16 |     -->
17 |     <link rel="manifest" href="%PUBLIC_URL%/manifest.json" />
18 |     <!--
19 |       Notice the use of %PUBLIC_URL% in the tags above.
20 |       It will be replaced with the URL of the `public` folder during the build.
21 |       Only files inside the `public` folder can be referenced from the HTML.
22 | 
23 |       Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
24 |       work correctly both with client-side routing and a non-root public URL.
25 |       Learn how to configure a non-root public URL by running `npm run build`.
26 |     -->
27 |     <title>React App</title>
28 |   </head>
29 |   <body>
30 |     <noscript>You need to enable JavaScript to run this app.</noscript>
31 |     <div id="root"></div>
32 |     <!--
33 |       This HTML file is a template.
34 |       If you open it directly in the browser, you will see an empty page.
35 | 
36 |       You can add webfonts, meta tags, or analytics to this file.
37 |       The build step will place the bundled scripts into the <body> tag.
38 | 
39 |       To begin the development, run `npm start` or `yarn start`.
40 |       To create a production bundle, use `npm run build` or `yarn build`.
41 |     -->
42 |   </body>
43 | </html>
44 | 


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/src/logo.svg:
--------------------------------------------------------------------------------
1 | <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 841.9 595.3">
2 |     <g fill="#61DAFB">
3 |         <path d="M666.3 296.5c0-32.5-40.7-63.3-103.1-82.4 14.4-63.6 8-114.2-20.2-130.4-6.5-3.8-14.1-5.6-22.4-5.6v22.3c4.6 0 8.3.9 11.4 2.6 13.6 7.8 19.5 37.5 14.9 75.7-1.1 9.4-2.9 19.3-5.1 29.4-19.6-4.8-41-8.5-63.5-10.9-13.5-18.5-27.5-35.3-41.6-50 32.6-30.3 63.2-46.9 84-46.9V78c-27.5 0-63.5 19.6-99.9 53.6-36.4-33.8-72.4-53.2-99.9-53.2v22.3c20.7 0 51.4 16.5 84 46.6-14 14.7-28 31.4-41.3 49.9-22.6 2.4-44 6.1-63.6 11-2.3-10-4-19.7-5.2-29-4.7-38.2 1.1-67.9 14.6-75.8 3-1.8 6.9-2.6 11.5-2.6V78.5c-8.4 0-16 1.8-22.6 5.6-28.1 16.2-34.4 66.7-19.9 130.1-62.2 19.2-102.7 49.9-102.7 82.3 0 32.5 40.7 63.3 103.1 82.4-14.4 63.6-8 114.2 20.2 130.4 6.5 3.8 14.1 5.6 22.5 5.6 27.5 0 63.5-19.6 99.9-53.6 36.4 33.8 72.4 53.2 99.9 53.2 8.4 0 16-1.8 22.6-5.6 28.1-16.2 34.4-66.7 19.9-130.1 62-19.1 102.5-49.9 102.5-82.3zm-130.2-66.7c-3.7 12.9-8.3 26.2-13.5 39.5-4.1-8-8.4-16-13.1-24-4.6-8-9.5-15.8-14.4-23.4 14.2 2.1 27.9 4.7 41 7.9zm-45.8 106.5c-7.8 13.5-15.8 26.3-24.1 38.2-14.9 1.3-30 2-45.2 2-15.1 0-30.2-.7-45-1.9-8.3-11.9-16.4-24.6-24.2-38-7.6-13.1-14.5-26.4-20.8-39.8 6.2-13.4 13.2-26.8 20.7-39.9 7.8-13.5 15.8-26.3 24.1-38.2 14.9-1.3 30-2 45.2-2 15.1 0 30.2.7 45 1.9 8.3 11.9 16.4 24.6 24.2 38 7.6 13.1 14.5 26.4 20.8 39.8-6.3 13.4-13.2 26.8-20.7 39.9zm32.3-13c5.4 13.4 10 26.8 13.8 39.8-13.1 3.2-26.9 5.9-41.2 8 4.9-7.7 9.8-15.6 14.4-23.7 4.6-8 8.9-16.1 13-24.1zM421.2 430c-9.3-9.6-18.6-20.3-27.8-32 9 .4 18.2.7 27.5.7 9.4 0 18.7-.2 27.8-.7-9 11.7-18.3 22.4-27.5 32zm-74.4-58.9c-14.2-2.1-27.9-4.7-41-7.9 3.7-12.9 8.3-26.2 13.5-39.5 4.1 8 8.4 16 13.1 24 4.7 8 9.5 15.8 14.4 23.4zM420.7 163c9.3 9.6 18.6 20.3 27.8 32-9-.4-18.2-.7-27.5-.7-9.4 0-18.7.2-27.8.7 9-11.7 18.3-22.4 27.5-32zm-74 58.9c-4.9 7.7-9.8 15.6-14.4 23.7-4.6 8-8.9 16-13 24-5.4-13.4-10-26.8-13.8-39.8 13.1-3.1 26.9-5.8 41.2-7.9zm-90.5 125.2c-35.4-15.1-58.3-34.9-58.3-50.6 0-15.7 22.9-35.6 58.3-50.6 8.6-3.7 18-7 27.7-10.1 5.7 19.6 13.2 40 22.5 60.9-9.2 20.8-16.6 41.1-22.2 60.6-9.9-3.1-19.3-6.5-28-10.2zM310 490c-13.6-7.8-19.5-37.5-14.9-75.7 1.1-9.4 2.9-19.3 5.1-29.4 19.6 4.8 41 8.5 63.5 10.9 13.5 18.5 27.5 35.3 41.6 50-32.6 30.3-63.2 46.9-84 46.9-4.5-.1-8.3-1-11.3-2.7zm237.2-76.2c4.7 38.2-1.1 67.9-14.6 75.8-3 1.8-6.9 2.6-11.5 2.6-20.7 0-51.4-16.5-84-46.6 14-14.7 28-31.4 41.3-49.9 22.6-2.4 44-6.1 63.6-11 2.3 10.1 4.1 19.8 5.2 29.1zm38.5-66.7c-8.6 3.7-18 7-27.7 10.1-5.7-19.6-13.2-40-22.5-60.9 9.2-20.8 16.6-41.1 22.2-60.6 9.9 3.1 19.3 6.5 28.1 10.2 35.4 15.1 58.3 34.9 58.3 50.6-.1 15.7-23 35.6-58.4 50.6zM320.8 78.4z"/>
4 |         <circle cx="420.9" cy="296.5" r="45.7"/>
5 |         <path d="M520.5 78.1z"/>
6 |     </g>
7 | </svg>
8 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
  1 | # React + TypeScript 实践入门
  2 | 
  3 | ## 环境
  4 | 1. `React>=16.9`
  5 | 
  6 | 2. `TypeScript>=3.6.2`
  7 | 
  8 | 3. `VS Code >=1.37.1`
  9 | 
 10 | 4. `yarn >= 1.17.3`
 11 | 
 12 | 5. `node >= 10.13.0`
 13 | 
 14 | ### VS Code + Chrome 调试支持
 15 | 1. 安装 [Chrome Debugger Extension](https://marketplace.visualstudio.com/items?itemName=msjsdiag.debugger-for-chrome) 插件 
 16 |    
 17 | 2. 启动配置参考  `.vscode/launch.json`
 18 |    
 19 | 3. 设置断点,按 F5 即可调试.
 20 | 
 21 | ### 配置 Prettier
 22 | 1. 安装 [Prettier](https://prettier.io/docs/en/editors.html)
 23 | 2. Pretter 的配置可以在 VS Code 的 Settings 里面配置.
 24 | 
 25 | ### 运行测试
 26 | 1. `yarn test` 
 27 | 2. `jest` 默认运行上次提交之后有修改文件的相关测试.
 28 | 3. 直接将测试代码写在 `it()` 全局函数或 `test()` 函数块里就好了. 也可以用 `describe()` 把这些 测试放在一个分组里.
 29 | 4. `jest` 自带了 `expect()` 全局函数用作断言语句.
 30 | 5. 简单的 Component 的测试参考  `App.test.tsx`
 31 | 6. 测试代码文件推荐跟源文件代码放在同一目录下. 支持 `.test.ts` 后缀 `.spec.ts` 后缀,(说明: ts 可以,那么 ,tsx,js,jsx 也可以.),或者放在 `__test__` 目录下.
 32 | 7. `xit()` 表示此测试暂时排序.
 33 | 8. `fit()` 表示暂时只运行此测试. `focus it`
 34 | 9. `yarn test -- --coverage` 可以输出测试覆盖率报告.
 35 | 10. 其他配置可以参考 `jest` 相关文档,然后在 `package.json` 中配置.
 36 | 
 37 | `test --env=node` 速度比较快.
 38 | 但是以下API 需要 `jsdom`
 39 | - 所有的浏览器特有的全局对象如 `window`,`document`
 40 | - `ReactDOM.render()`
 41 | - `TestUtils.renderIntoDocument()`
 42 | - Enzyme 中的  `mount()` 
 43 | 
 44 | 不过下面的 API不需要 `jsdom`
 45 | - `TestUtils.createRenderer()`
 46 | - Enzyme 中的 `shallow()`
 47 | - 快照测试也不需要 `jsdom`
 48 | 
 49 | 最后可以安装 VS Code 的 [Jest 插件](https://github.com/orta/vscode-jest)
 50 | 
 51 | ### Debug 测试
 52 | 参考 [Debugging Tests](https://create-react-app.dev/docs/debugging-tests)
 53 | 
 54 | 1. 在 Chrome 中测试 
 55 |    - `yarn test:debug`
 56 |    - 打开 Chrome 输入 `about:inspect` 选择调试页面进程.
 57 | 
 58 | 2. 在 VS Code 中测试
 59 |   执行 已经配置的 Debug CRA Tests 启动项即可. (先按 <C+Shift+D>)
 60 | 
 61 | ## 各分支对应 Demo 索引
 62 | 
 63 | 1. [demo-try](https://github.com/banxi1988/learn-react/tree/demo-try)
 64 | 
 65 | 
 66 | ## 以下是项目初始说明
 67 | 
 68 | This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).
 69 | 
 70 | ## Available Scripts
 71 | 
 72 | In the project directory, you can run:
 73 | 
 74 | ### `yarn start`
 75 | 
 76 | Runs the app in the development mode.<br>
 77 | Open [http://localhost:3000](http://localhost:3000) to view it in the browser.
 78 | 
 79 | The page will reload if you make edits.<br>
 80 | You will also see any lint errors in the console.
 81 | 
 82 | ### `yarn test`
 83 | 
 84 | Launches the test runner in the interactive watch mode.<br>
 85 | See the section about [running tests](https://facebook.github.io/create-react-app/docs/running-tests) for more information.
 86 | 
 87 | ### `yarn  build`
 88 | 
 89 | Builds the app for production to the `build` folder.<br>
 90 | It correctly bundles React in production mode and optimizes the build for the best performance.
 91 | 
 92 | The build is minified and the filenames include the hashes.<br>
 93 | Your app is ready to be deployed!
 94 | 
 95 | See the section about [deployment](https://facebook.github.io/create-react-app/docs/deployment) for more information.
 96 | 
 97 | ### `yarn eject`
 98 | 
 99 | **Note: this is a one-way operation. Once you `eject`, you can’t go back!**
100 | 
101 | If you aren’t satisfied with the build tool and configuration choices, you can `eject` at any time. This command will remove the single build dependency from your project.
102 | 
103 | Instead, it will copy all the configuration files and the transitive dependencies (Webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except `eject` will still work, but they will point to the copied scripts so you can tweak them. At this point you’re on your own.
104 | 
105 | You don’t have to ever use `eject`. The curated feature set is suitable for small and middle deployments, and you shouldn’t feel obligated to use this feature. However we understand that this tool wouldn’t be useful if you couldn’t customize it when you are ready for it.
106 | 
107 | ## Learn More
108 | 
109 | You can learn more in the [Create React App documentation](https://facebook.github.io/create-react-app/docs/getting-started).
110 | 
111 | To learn React, check out the [React documentation](https://reactjs.org/).
112 | 


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/src/serviceWorker.ts:
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  1 | // This optional code is used to register a service worker.
  2 | // register() is not called by default.
  3 | 
  4 | // This lets the app load faster on subsequent visits in production, and gives
  5 | // it offline capabilities. However, it also means that developers (and users)
  6 | // will only see deployed updates on subsequent visits to a page, after all the
  7 | // existing tabs open on the page have been closed, since previously cached
  8 | // resources are updated in the background.
  9 | 
 10 | // To learn more about the benefits of this model and instructions on how to
 11 | // opt-in, read https://bit.ly/CRA-PWA
 12 | 
 13 | const isLocalhost = Boolean(
 14 |   window.location.hostname === 'localhost' ||
 15 |     // [::1] is the IPv6 localhost address.
 16 |     window.location.hostname === '[::1]' ||
 17 |     // 127.0.0.1/8 is considered localhost for IPv4.
 18 |     window.location.hostname.match(
 19 |       /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
 20 |     )
 21 | );
 22 | 
 23 | type Config = {
 24 |   onSuccess?: (registration: ServiceWorkerRegistration) => void;
 25 |   onUpdate?: (registration: ServiceWorkerRegistration) => void;
 26 | };
 27 | 
 28 | export function register(config?: Config) {
 29 |   if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
 30 |     // The URL constructor is available in all browsers that support SW.
 31 |     const publicUrl = new URL(
 32 |       (process as { env: { [key: string]: string } }).env.PUBLIC_URL,
 33 |       window.location.href
 34 |     );
 35 |     if (publicUrl.origin !== window.location.origin) {
 36 |       // Our service worker won't work if PUBLIC_URL is on a different origin
 37 |       // from what our page is served on. This might happen if a CDN is used to
 38 |       // serve assets; see https://github.com/facebook/create-react-app/issues/2374
 39 |       return;
 40 |     }
 41 | 
 42 |     window.addEventListener('load', () => {
 43 |       const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
 44 | 
 45 |       if (isLocalhost) {
 46 |         // This is running on localhost. Let's check if a service worker still exists or not.
 47 |         checkValidServiceWorker(swUrl, config);
 48 | 
 49 |         // Add some additional logging to localhost, pointing developers to the
 50 |         // service worker/PWA documentation.
 51 |         navigator.serviceWorker.ready.then(() => {
 52 |           console.log(
 53 |             'This web app is being served cache-first by a service ' +
 54 |               'worker. To learn more, visit https://bit.ly/CRA-PWA'
 55 |           );
 56 |         });
 57 |       } else {
 58 |         // Is not localhost. Just register service worker
 59 |         registerValidSW(swUrl, config);
 60 |       }
 61 |     });
 62 |   }
 63 | }
 64 | 
 65 | function registerValidSW(swUrl: string, config?: Config) {
 66 |   navigator.serviceWorker
 67 |     .register(swUrl)
 68 |     .then(registration => {
 69 |       registration.onupdatefound = () => {
 70 |         const installingWorker = registration.installing;
 71 |         if (installingWorker == null) {
 72 |           return;
 73 |         }
 74 |         installingWorker.onstatechange = () => {
 75 |           if (installingWorker.state === 'installed') {
 76 |             if (navigator.serviceWorker.controller) {
 77 |               // At this point, the updated precached content has been fetched,
 78 |               // but the previous service worker will still serve the older
 79 |               // content until all client tabs are closed.
 80 |               console.log(
 81 |                 'New content is available and will be used when all ' +
 82 |                   'tabs for this page are closed. See https://bit.ly/CRA-PWA.'
 83 |               );
 84 | 
 85 |               // Execute callback
 86 |               if (config && config.onUpdate) {
 87 |                 config.onUpdate(registration);
 88 |               }
 89 |             } else {
 90 |               // At this point, everything has been precached.
 91 |               // It's the perfect time to display a
 92 |               // "Content is cached for offline use." message.
 93 |               console.log('Content is cached for offline use.');
 94 | 
 95 |               // Execute callback
 96 |               if (config && config.onSuccess) {
 97 |                 config.onSuccess(registration);
 98 |               }
 99 |             }
100 |           }
101 |         };
102 |       };
103 |     })
104 |     .catch(error => {
105 |       console.error('Error during service worker registration:', error);
106 |     });
107 | }
108 | 
109 | function checkValidServiceWorker(swUrl: string, config?: Config) {
110 |   // Check if the service worker can be found. If it can't reload the page.
111 |   fetch(swUrl)
112 |     .then(response => {
113 |       // Ensure service worker exists, and that we really are getting a JS file.
114 |       const contentType = response.headers.get('content-type');
115 |       if (
116 |         response.status === 404 ||
117 |         (contentType != null && contentType.indexOf('javascript') === -1)
118 |       ) {
119 |         // No service worker found. Probably a different app. Reload the page.
120 |         navigator.serviceWorker.ready.then(registration => {
121 |           registration.unregister().then(() => {
122 |             window.location.reload();
123 |           });
124 |         });
125 |       } else {
126 |         // Service worker found. Proceed as normal.
127 |         registerValidSW(swUrl, config);
128 |       }
129 |     })
130 |     .catch(() => {
131 |       console.log(
132 |         'No internet connection found. App is running in offline mode.'
133 |       );
134 |     });
135 | }
136 | 
137 | export function unregister() {
138 |   if ('serviceWorker' in navigator) {
139 |     navigator.serviceWorker.ready.then(registration => {
140 |       registration.unregister();
141 |     });
142 |   }
143 | }
144 | 


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