rollup.config.js

import commonjs from '@rollup/plugin-commonjs';
import typescript from 'rollup-plugin-typescript2';
import pkg from './package.json' assert {type: 'json'};

const globals = {
    react: 'React',
    'react-dom': 'ReactDOM',
};
const input = ['src/index.tsx'];
const output = {
    entryFileNames: '[name].js',
    esModule: true,
    exports: 'auto',
    globals,
    preserveModules: true,
    preserveModulesRoot: 'src',
    sourcemap: true,
};

const external = [
    ...Object.keys(pkg.dependencies || {}),
    ...Object.keys(pkg.peerDependencies || {}),
];

const commonjsOptions = {};

const rollupConfig = [
    {
        input,
        output: {
            ...output,
            dir: 'dist/cjs',
            format: 'cjs',
        },
        external,
        plugins: [
            commonjs(commonjsOptions),
            typescript({
                tsconfigOverride: {
                    compilerOptions: {
                        declarationDir: 'dist/cjs',
                    },
                },
            }),
        ],
    },
    {
        input,
        output: {
            ...output,
            dir: 'dist/esm',
            format: 'esm',
        },
        external,
        plugins: [
            commonjs(commonjsOptions),
            typescript({
                tsconfigOverride: {
                    compilerOptions: {
                        declarationDir: 'dist/esm',
                    },
                },
            }),
        ],
    },
];

export default rollupConfig;