babel-plugin-remove-ungap

Remove @ungap ponyfills

Install babel-plugin-remove-ungap

npm i -D babel-plugin-remove-ungap

Usage

Add remove-ungap to your babelrc plugins if the ponyfills are not needed by your browser target. This could be due to only targeting modern browsers or because your project already polyfills the browser.

This plugin works with CJS and ES modules before bundling. It can be run by rollup-plugin-babel before import or require statements are altered.

exclude option

You can add the exclude option to block removal/processing of specific @ungap modules.

{
    plugins: [
        ['remove-ungap', {
            exclude: [
                '@ungap/essential-map'
            ]
        }]
    ]
}

This config will cause any import of @ungap/essential-map to be preserved.

future option

Some @ungap polyfills are needed by most current browsers or did not exist when the current semver-major of this plugin was released. These are only processed if explicitly requested by the future option. For example:

{
    plugins: [
        ['remove-ungap', {
            future: [
                '@ungap/from-entries'
            ]
        }]
    ]
}

Unknown modules are ignored.

Modules that are removed

Module	Target	Declares variable
@ungap/assign	Object.assign	Yes
@ungap/array-iterator	Array.prototype[Symbol.iterator]	Yes
@ungap/custom-event	CustomEvent
@ungap/essential-map	Map
@ungap/essential-set	Set
@ungap/essential-symbol	Symbol
@ungap/essential-weakset	WeakSet
@ungap/event	Event
@ungap/event-target	EventTarget
@ungap/import-node	document.importNode	Yes
@ungap/is-array	Array.isArray	Yes
@ungap/map	Map
@ungap/set	Set
@ungap/template-literal	val => val	Yes
@ungap/trim	String.prototype.trim	Yes
@ungap/weakmap	WeakMap
@ungap/weakset	WeakSet

@ungap/create-content is altered

@ungap/create-content is altered so that HAS_CONTENT is constant true. This allows minifiers to strip code that is not useed by modern browsers.

Modules that can be removed by the future option

Module	Target	Declares variable
@ungap/from-entries	Object.fromEntries	Yes
@ungap/global-this	globalThis
@ungap/promise-all-settled	Promise.allSettled	Yes
@ungap/promise-any	Promise.any	Yes
@ungap/template-tag-arguments	(...args) => args	Yes

Running tests

Tests are provided by xo and ava.

npm install
npm test