rollup.config.js

import babel from '@rollup/plugin-babel';
import commonjs from '@rollup/plugin-commonjs';
import filesize from 'rollup-plugin-filesize';
import json from '@rollup/plugin-json';
import replace from '@rollup/plugin-replace';
import resolve from '@rollup/plugin-node-resolve';
import sizes from 'rollup-plugin-sizes';
import wasm from '@rollup/plugin-wasm';
import webWorkerLoader from 'rollup-plugin-web-worker-loader';
import terser from '@rollup/plugin-terser';
import alias from '@rollup/plugin-alias';
import virtual from '@rollup/plugin-virtual';

const isProduction = process.env.NODE_ENV?.startsWith('prod');

const config = {
	input: './src/js/main.js',
	external: [
		'/static/js/citeproc-rs/citeproc_rs_wasm.js',
		'cross-fetch/polyfill'
	],
	output: {
		dir: './build/static',
		format: 'iife',
		sourcemap: !isProduction,
		compact: isProduction
	},
	treeshake: {
		moduleSideEffects: 'no-external',
	},
	plugins: [
		resolve({
			preferBuiltins: false,
			mainFields: ['browser', 'module', 'main'],
			extensions: ['.js', '.jsx', '.wasm'],
		}),
		json(),
		wasm(),
		webWorkerLoader({
			targetPlatform: 'browser',
			skipPlugins: ['resolve', 'json', 'wasm', 'commonjs', 'replace', 'babel', 'sizes', 'filesize']
		}),
		commonjs(),
		replace({
			preventAssignment: true,
			'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV ?? 'development'),
		}),
		babel({
			exclude: "node_modules/**",
			extensions: ['.js', '.jsx'],
			babelHelpers: 'runtime'
		}),
		filesize({ showMinifiedSize: false, showGzippedSize: !!process.env.DEBUG }),
	]
};

if(process.env.DEBUG) {
	config.plugins.splice(-1, 0, sizes());
}

if(isProduction) {
	config.plugins.splice(0, 0, alias({
		entries: [{
			find: '@formatjs/icu-messageformat-parser',
			replacement: '@formatjs/icu-messageformat-parser/no-parser'
		}]
	}));
	config.plugins.push(terser({ safari10: true }));
	config.external.push('./wdyr'); //exclude why-did-you-render from production
} else {
	config.plugins.splice(0, 0, virtual({
		'../../lang/compiled/en-US.json': 'export default {}',
	}),)
}

export default config;