webpack.config.js

const path = require('path');

module.exports = {
    mode: process.env.NODE_ENV || 'development',
    entry: './src/app.tsx',
    output: {
        filename: 'main.js',
        path: path.resolve(__dirname, 'dist'),
    },
    resolve: {
        extensions: ['.js', '.ts', '.tsx']
    },
    module: {
        rules: [
            {
                // .jsもしくは.tsを対象とする
                test: /\.(j|t)sx?$/,
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader',
                    options: {
                        presets: [
                            '@babel/preset-env',
                            '@babel/preset-react',
                            '@babel/preset-typescript'
                        ]
                    }
                }
            }
        ]
    },
    devServer: {
        contentBase: __dirname,
        port: 5000
    },
};