anireact/rollup-plugin-override

README

Rollup Plugin Override

Compile-time expression substitution. Similar to @rollup/plugin-replace, but robust and safe.

Usage

yarn add -D @anireact/rollup-plugin-override

npm install --save-dev @anireact/rollup-plugin-override

import override from '@anireact/rollup-plugin-override';

export default {
    plugins: [
        override({
            mappings: {
                'process.env.NODE_ENV': `'production'`,
                'OPT_LEVEL': `3`,
                'BUILD_ID': JSON.stringify(uuid()),
            },
        }),
    ],
};

Options

include, exclude — filter patterns to limit files the plugin processes.
ignoreScope (default: false) — force enable replacement processing even in scopes that have bindings, shadowing the expression to be rewritten.
mappings — a record of key-value mappings; values must be strings containing valid JavaScript expressions.

Why

Unlike the official @rollup/plugin-replace, this plugin is more robust in edge cases:

Doesn’t care of the exact code formatting:

assert(process.env.NODE_ENV === 'production');
assert(process.env['NODE_ENV'] === 'production');
assert(process['env'][`NODE_ENV`] === 'production');

assert(
    process
    .env
    .NODE_ENV === 'production'
);

Doesn’t rewrite binding names, assignment LHS expressions, etc.:

process.env.NODE_ENV = 'production';
//          ↑ writing the real env variable

import { BUILD_ID } from '#constants';

const { BUILD_ID } = whatever;
const f = BUILD_ID => g();

class App {
    BUILD_ID;
    OPT_LEVEL() {}
}

Respects the scope:

const f = BUILD_ID => g(BUILD_ID);
//                      ↑ “global” `BUILD_ID` is shadowed
//                        by the function parameter,
//                        so it will not be rewritten

import process from 'node:process';

console.log(process.env.NODE_ENV);
//                      ↑ reading the real env variable

Limitations

No expressions except plain identifiers and member expressions can be rewritten.
Member expression properties must be either plain identifiers, or string/template literal subscripts.
Template literals with substitutions are not supported.
The value of string or template literal must be a valid JavaScript identifier.

Why Babel

Because it has an easy to use all-in-one API.

Support

If you have any issues, feel free to fork this plugin, or contact me on Telegram https://t.me/miyaokamarina.

License