JavaScript private class methods with Snowpack
Snowpack Plugin: snowpack-plugin-acorn-injection
Expanding off of @noseratio's work, I have created a NPM dependency called snowpack-plugin-acorn-injection
that will inject the relevant Acorn plugins into Rollup's internal configuration.
The plugin is available:
- on NPM: https://www.npmjs.com/package/snowpack-plugin-acorn-injection
- on GitHub: https://github.com/concision/snowpack-plugin-acorn-injection
Example
Dependency Installation
Install the plugin and the relevant Acorn plugin(s) that are desired (for example, acorn-stage3
) as development dependencies.
Steps:
- npm:
npm install --save-dev snowpack-plugin-acorn-injection acorn-stage3
- Yarn:
yarn add --dev snowpack-plugin-acorn-injection acorn-stage3
Configure Snowpack
Configure the project's Snowpack configuration with snowpack-plugin-acorn-injection
and the relevant Acorn plugins:
{
...
"plugins": [
[
"snowpack-plugin-acorn-injection",
{
"plugins": [
"acorn-stage3"
]
}
]
],
...
}
I've figured it out, using Rollup.js options
hook and acorn-stage3
acorn plugin, repo.
acorn-private-methods
can be used as well (if only private methods wanted).
- Create a custom Rollup.js plugin, I called it
@noseratio/rollup-acorn-conf
:
"use strict";
module.exports = function plugin(hostOpts = {}) {
return {
name: 'rollup-acorn-conf',
options: rollupOpts => {
console.log("Enabling 'acorn-stage3'...");
rollupOpts.acorn = rollupOpts.acorn ?? {};
rollupOpts.acorn.ecmaVersion = 2020;
rollupOpts.acornInjectPlugins = rollupOpts.acornInjectPlugins ?? [];
rollupOpts.acornInjectPlugins.push(require('acorn-stage3'));
return rollupOpts;
}
};
};
Its package.json
:
{
"name": "@noseratio/rollup-acorn-conf",
"version": "0.1.1",
"description": "Enable ES2020 features (Stage 3) for Rollup.js",
"homepage": "https://github.com/noseratio/snowpack-discussions-1209",
"main": "index.js",
"scripts": {},
"devDependencies": {
"acorn-stage3": "^4.0.0"
}
}
- In
snowpack.config.js
:
installOptions: {
rollup: {
plugins: [require('@noseratio/rollup-acorn-conf')()]
}
}