Rollup-plugin-pure NPM

`rollup-plugin-pure`

Automatically add /* #__PURE__ */ annotations before definition functions

Features

⚡️ avoids end-users bundling unused code

How it works

Definition functions (for example, in Vue with defineComponent) are increasingly common but do not play nice with tree-shaking. It's not possible to tell whether or not a function call which receives an object can be tree-shaken from a build, as it's possible there might be side effects.

Rollup supports /* @__PURE__ */ annotations to declare this from a library author's point of view, but it can be tricky when we know that every occurrence of a function call is pure.

This plugin will automatically inject the annotation before any occurrence of the function call, as well as injecting /* @__NO_SIDE_EFFECTS__ */ annotations in front of function declarations.

Installation

Install and add rollup-plugin-pure to your Vite or Rollup config.

pnpm add -D rollup-plugin-pure

import { PluginPure } from 'rollup-plugin-pure'
import { defineConfig } from 'vite'

export default defineConfig({
  plugins: [
    PluginPure({
      functions: ['defineComponent'],
      include: [/(?<!im)pure\.js$/],
      // exclude: [],
      // sourcemap: true,
    }),
  ],
})