Can I tell rollup to not minimize the code it generates?

Question

I understand that I can generate a source map, but I want to generate the rollup output without minification. Is it possible to do this? I've googled and haven't found anybody asking this question.

Enclose

doesn't rollup only minify if you use an external minification plugin like terser? – Ericerica

@Ericerica the documentation suggests otherwise: there is an option on whether or not to output a source map – Enclose

Answer 1

usually with rollup:

javascript is minified by @rollup/plugin-terser
to disable minifacation of javascript
remove terser() from the plugins array in rollup.config.js

by default, CSS is not minified by rollup-plugin-css-only or rollup-plugin-postcss

rollup-plugin-css-only has no option for minify
css({ output: 'bundle.css' })

rollup-plugin-postcss has the default option { minimize: false }
postcss({ extract: 'bundle.css' })

other rollup plugins can produce minified CSS, for example rollup-plugin-svelte

as a workaround, to produce pretty CSS, im using the build script
rollup -c && prettier -w public/build/bundle.css
with npm i -D prettier

all of this may be simpler when migrating from rollup to vite
see also How do I disable minification when running "build" command in sveltekit?
and sveltejs: Switch existing project from rollup to vite
and awesome-vite

example vite.config.js

import { defineConfig } from 'vite';
import { svelte } from '@sveltejs/vite-plugin-svelte';

export default defineConfig({
  // use relative paths to asset files
  // https://github.com/vitejs/vite/issues/762
  base: './',
  plugins: [
    svelte(),
  ],
  build: {
    // dont minify JS and CSS
    minify: false,
    rollupOptions: {
      output: {
        // remove hashes from output paths
        // https://github.com/vitejs/vite/issues/378
        entryFileNames: `assets/[name].js`,
        chunkFileNames: `assets/[name].js`,
        assetFileNames: `assets/[name].[ext]`
      }
    }
  },
});

Deraign

Answer 2

First of all, this question (or one similar) was asked here.

It seems that there isn't a way to do it based on that. I don't know what your exact use case for this is, but maybe you can run it through rollup-plugin-esformatter to make your code readable.

Triage

I did find that answer, but it seemed to be for an unrelated project, so I didn't put too much weight into the replies – Enclose

The use case for me is easy debugging. Is there a method others use for this? – Flattish

@Flattish Source maps? – Triage