steer-react-scripts如何优化打包速度的代码实现

steer-react-scripts是基于create-react-app的自定义脚本，它的打包速度优化可以通过配置webpack进行实现。下面给出一些具体的代码实现：

1. 代码分割

// webpack.config.js
module.exports = {
  optimization: {
    splitChunks: {
      cacheGroups: {
        commons: {
          test: /[\\/]node_modules[\\/]/,
          name: 'vendors',
          chunks: 'all',
        },
      },
    },
  },
};

2. Tree Shaking

// webpack.config.js
module.exports = {
  mode: 'production',
  optimization: {
    usedExports: true,
    sideEffects: true,
  },
};

3. 懒加载

// App.js
import React, { lazy, Suspense } from 'react';

const OtherComponent = lazy(() => import('./OtherComponent'));

function MyComponent() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <OtherComponent />
      </Suspense>
    </div>
  );
}

4. 开启缓存

// webpack.config.js
module.exports = {
  module: {
    rules: [
      {
        test: /\.js$/,
        use: ['cache-loader', 'babel-loader'],
        include: path.resolve(__dirname, 'src'),
      },
    ],
  },
};

5. 优化资源

// webpack.config.js
module.exports = {
  module: {
    rules: [
      {
        test: /\.(png|jpe?g|gif)$/i,
        use: [
          {
            loader: 'url-loader',
            options: {
              limit: 8192,
              name: '[name].[ext]',
              outputPath: 'images',
            },
          },
        ],
      },
      {
        test: /\.(woff|woff2|eot|ttf|otf)$/i,
        type: 'asset/resource',
        generator: {
          filename: 'fonts/[name][ext]',
        },
      },
    ],
  },
};

6. 优化babel配置

// babel.config.js
module.exports = {
  presets: ['@babel/preset-env', '@babel/preset-react'],
  plugins: ['@babel/plugin-transform-runtime'],
};

7. 优化webpack配置

// webpack.config.js
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer')
  .BundleAnalyzerPlugin;

module.exports = {
  plugins: [new BundleAnalyzerPlugin()],
};

以上是一些steer-react-scripts优化打包速度的代码实现，具体实现可以根据实际情况进行调整和优化。