Jordan Harband

Airbnb's ESLint config, following our styleguide

JavaScript Testing utilities for React

JavaScript Testing utilities for React

React specific linting rules for ESLint

A querystring parser that supports nesting and arrays, with a depth limit

ECMAScript 5 compatibility shims for legacy JavaScript engines

Import with sanity.

Runtime type checking for React props and similar objects.

Give your JavaScript the ability to speak many languages.

Static AST checker for accessibility rules on JSX elements.

ECMAScript 6 (Harmony) compatibility shims for legacy JavaScript engines

A library to create readable "multipart/form-data" streams. Can be used to submit forms and file uploads to other web applications.

An easy way to create, parse, and validate forms

resolve like require.resolve() on behalf of files asynchronously and synchronously

Fix babel/babel#2212

A React component for dealing with clicks outside its subtree

Babel plugin to transpile import() to a deferred require(), for node

A babel plugin that optimizes and inlines SVGs for your react components.

The core `url` packaged standalone for use with Browserify.

The assert module from Node.js, for the browser.

Programmatic access to the ARIA specification

Streamable SHA hashes in pure javascript

For use with React PropTypes. Will error on any prop not explicitly specified.

Find built-in ESLint rules you don't have in your custom config.

This library provides the functionality of PBKDF2 with the ability to use any supported hashing algorithm returned from crypto.getHashes()

ECMAScript 7 compatibility shims for legacy JavaScript engines

AST utility module for statically analyzing JSX

string representations of objects in node and the browser

ECMAScript spec-compliant polyfill/shim for `globalThis`

Implementation of Function.prototype.bind

ES Proposal spec-compliant shim for Promise.prototype.finally

A port of jQuery.extend that actually works on node.js

ECMAScript spec abstract operations.

ES6 spec-compliant Object.assign shim. From https://github.com/es-shims/es6-shim

ES Proposal spec-compliant shim for Promise.allSettled

Is the current JS environment a touch device?

ES2017 spec-compliant Object.values shim.

Template tag that takes out unwanted newlines

ES2017 spec-compliant Object.entries shim.

Determine if your dependency graph's stated "engines" criteria is met.

Determine if a function is a native generator function.

adds node crypto signing for browsers

An Object.keys replacement, in case Object.keys is not available. From https://github.com/es-shims/es5-shim

An ES7/ES2016 spec-compliant `Array.prototype.includes` shim/polyfill/replacement that works as far down as ES3.

Is this JS value callable? Works with Functions and GeneratorFunctions, despite ES6 @@toStringTag.

Array.prototype.find ES6 polyfill.

An ESnext spec-compliant `DisposableStack`, `AsyncDisposableStack`, `Symbol.dispose`, and `Symbol.asyncDispose` shim/polyfill/replacement that works as far down as ES3.

Spec-compliant polyfill for String.prototype.replaceAll ESnext proposal

Get and robustly cache all JS language-level intrinsics at first require time

Compute ripemd160 of bytes or strings.

Programmatic access to information about the AXObject Model

An ES2019 spec-compliant `Array.prototype.flatMap` shim/polyfill/replacement that works as far down as ES3.

ES proposal-spec-compliant Object.fromEntries shim.

An ES2019 spec-compliant `Array.prototype.flat` shim/polyfill/replacement that works as far down as ES3.

An ES-spec-compliant (proposed) Array.prototype.at shim/polyfill/replacement that works as far down as ES3

Pass in a string, array, Buffer, Data View, or Uint8Array, and get a Buffer back.

Command line tool for creating or updating a .npmignore file based on .gitignore.

Array.prototype.findIndex ES2015 polyfill.

Is this specifier a node.js core module?

ES2015-compliant shim for Object.is - differentiates between -0 and +0

Is this value a JS regex? Works cross-realm/iframe, and despite ES6 @@toStringTag

Determine if a function is an ES6 arrow function or not.

A better forEach

ES2017 spec-compliant String.prototype.padStart shim.

abstract base class for crypto-streams

ECMAScript “ToPrimitive” algorithm. Provides ES5 and ES2015 versions.

Is this value a JS String object or primitive? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Checks whether a value is an object

Returns true if a value has the characteristics of a valid JavaScript data descriptor.

Define multiple non-enumerable properties at once. Uses `Object.defineProperty` when available; falls back to standard assignment in older engines.

My shareable eslint config

An ESnext spec-compliant iterator helpers shim/polyfill/replacement that works as far down as ES3.

ES2017 spec-compliant shim for `Object.getOwnPropertyDescriptors` that works in ES5.

RSA for browserify

Determine if a value is an ES6 Symbol or not.

Determine if the JS environment has Symbol support. Supports spec, or shams.

Is this value negative zero? === will lie to you

Determine if a function is a native async function.

Is this an arguments object? It's a harder question than you think.

Spec-compliant polyfill for String.prototype.matchAll

ES spec-compliant shim for Object.hasOwn

Is this value a JS Date object? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Returns true if a value has the characteristics of a valid JavaScript accessor descriptor.

ES 2021 spec-compliant shim for Promise.any

ES Proposal spec-compliant shim for AggregateError

ES5 spec-compliant shim for String.prototype.trim

Get an iterator for any JS language value. Works robustly across all environments, all versions.

Is this value a JS ArrayBuffer?

A better [].reduce

Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for data descriptors and accessor descriptors.

An ES2015 spec-compliant `Function.prototype.name` shim

ES2015-compliant shim for Number.isNaN - the global isNaN returns false positives.

Is this value a JS Typed Array? This module works cross-realm/iframe, does not depend on `instanceof` or mutable properties, and despite ES6 Symbol.toStringTag.

Cross-platform library for getting JSON docs

uglify require hook

abstract base class for hash-streams

An ESnext spec-compliant `Array.prototype.toSorted` shim/polyfill/replacement that works as far down as ES3.

ES2017 spec-compliant String.prototype.padEnd shim.

A simple cache for a few of the JS Error constructors.

Accept an optional node-style callback, and also return a spec-compliant Promise!

Does this JS environment support the `name` property on functions?

Is this value a JS Map? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

ES spec-like internal slots

ES6 spec-compliant RegExp.prototype.flags shim.

ES2019 spec-compliant String.prototype.trimLeft shim.

ES2019 spec-compliant String.prototype.trimLeft shim.

Is this value a JS Number object? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Determine if the JS environment has BigInt support.

Is this value a JS Boolean? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Give a regex, get a robust predicate function that tests it against a string.

Does the current node version have support for the "exports" field in package.json?

Determine if the JS environment has template literal support.

An ES5 spec-compliant `Array.prototype.every` shim/polyfill/replacement that works as far down as ES3.

Is this value an ES BigInt?

Given an object and a property, replaces a property descriptor (or deletes it), and returns a thunk to restore it.

A useful wrapper for `util.parseArgs`

ES2015 spec-compliant shim for Reflect.ownKeys

Does this environment have the ability to get the [[Prototype]] of an object on creation with `__proto__`?

A function that returns the normally hidden `AsyncFunction` constructor

Helper functions around Function call/apply/bind, for use in `call-bind`

Determine if the JS environment has `Symbol.toStringTag` support. Supports spec, or shams.

ES2019 spec-compliant String.prototype.trimEnd shim.

ES Object-related atoms: Object, ToObject, RequireObjectCoercible

Get the ArrayBuffer out of a TypedArray, robustly.

An ESnext spec-compliant `Array.prototype.findLast` shim/polyfill/replacement that works as far down as ES3.

An ESnext spec-compliant `Object.groupBy` shim/polyfill/replacement that works as far down as ES3.

An ES5 spec-compliant `Array.prototype.reduce` shim/polyfill/replacement that works as far down as ES3.

An ES5 spec-compliant `Array.prototype.map` shim/polyfill/replacement that works as far down as ES3.

An ES5 spec-compliant `Array.prototype.filter` shim/polyfill/replacement that works as far down as ES3.

ES2019 spec-compliant String.prototype.trimStart shim.

Firefox 17-26 iterators throw a StopIteration object to indicate "done". This normalizes it.

An ESnext spec-compliant shim/polyfill/replacement for all Well-Known Symbols that works in any environment with Symbols.

Function that returns an arbitrary `async function`, or undefined if `async function` syntax is unsupported.

Define a data property on an object. Will fall back to assignment in an engine without descriptors.

An ES2015 mostly-spec-compliant `Reflect.getPrototypeOf` sham/polyfill/replacement that works in as many engines as possible

An ESnext spec-compliant `Array.prototype.findLastIndex` shim/polyfill/replacement that works as far down as ES3.

ES spec-compliant shim for TypedArray.prototype.slice

JSON without touching any globals

Fixtures of ES values, for testing purposes

Does the environment have full property descriptor support? Handles IE 8's broken defineProperty/gOPD.

Gets the description of a Symbol. Handles `Symbol()` vs `Symbol('')` properly when possible.

Is this value a JS WeakRef? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Is this value a JS SharedArrayBuffer?

Is this value a JS Set? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Is this value a JS WeakMap? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Is this value a JS WeakSet? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Does the current environment have `import()` support?

An ES5 mostly-spec-compliant `Object.getPrototypeOf` sham/polyfill/replacement that works in as many engines as possible

ES Proposal spec-compliant shim for SuppressedError

Function that returns an arbitrary arrow function, or undefined if arrow function syntax is unsupported.

Iterate any iterable JS value. Works robustly in all environments, all versions.

Get the byteLength out of a DataView, robustly.

Get the byteOffset out of a DataView, robustly.

Is this value a JS DataView? This module works cross-realm/iframe, does not depend on `instanceof` or mutable properties, and despite ES6 Symbol.toStringTag.

Get the ArrayBuffer out of a DataView, robustly.

ES Math-related intrinsics and helpers, robustly cached.

Is this value a JS FinalizationRegistry? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

Helper package to shim a method into `Array.prototype[Symbol.unscopables]`

A helper to optimistically set Symbol.toStringTag, when possible.

A robust, ES3 compatible, "has own property" predicate.

Get the byte length of an ArrayBuffer, even in engines without a `.byteLength` method.

Define an accessor property on an object. Will either throw, or fall back to assignment in loose mode, in an engine without descriptors.

A function that returns the normally hidden `GeneratorFunction` constructor

Encode and decode HTML entities

Iterate any JS iterator. Works robustly in all environments, all versions.

An ES spec-compliant `Array.prototype.forEach` shim/polyfill/replacement that works as far down as ES3.

An ES5 spec-compliant `Array.prototype.some` shim/polyfill/replacement that works as far down as ES3.

Determine if the current node version supports the `--preserve-symlinks` flag.

Info about node `exports` field support: version ranges, categories, etc.

If available, the `Object.prototype.__proto__` accessor and mutator, call-bound

A simple list of possible Typed Array names.

Function that returns an arbitrary async generator function, or undefined if async generator syntax is unsupported.

ES spec-compliant shim for ArrayBuffer.prototype.slice

An ESnext spec-compliant `Array.prototype.toReversed` shim/polyfill/replacement that works as far down as ES3.

A function that returns the normally hidden `AsyncGeneratorFunction` constructor

parse arguments with recursive contexts

Robustly get the byte offset of a Typed Array

Robustly get the byte length of a Typed Array

Robustly get the length of a Typed Array

code coverage command con coverify

Port of jQuery.extend for node.js and the browser

Set a function's length property

Set a function's name property

tap-producing test harness for node and browsers

the definitive JavaScript type testing library

Store information about any JS value in a side channel, using a Map

Store information about any JS value in a side channel. Uses WeakMap if available.

Store information about any JS value in a side channel, using a linked list

Store information about any JS value in a side channel. Uses WeakMap if available.

implementation of crypto for the browser

Robust call-bound JavaScript intrinsics, using `call-bind` and `get-intrinsic`.

Returns an array of Typed Array names that are available in the current environment

Which kind of Typed Array is this JavaScript value? Works cross-realm, without `instanceof`, and despite Symbol.toStringTag.

Robustly `.call.bind()` a function

Unbox a boxed JS primitive value.

Which kind of Collection (Map, Set, WeakMap, WeakSet) is this JavaScript value? Works cross-realm, without `instanceof`, and despite Symbol.toStringTag.

parse argument options

`Object.defineProperty`, but not IE 8's broken one.

`Object.getOwnPropertyDescriptor`, but accounts for IE's broken implementation.

Robustly get the [[Prototype]] of an object

TypedArray polyfill for old browsers

concatenative mapdashery

Which kind of boxed JS primitive is this?

`Array.prototype.concat`, but made safe by ignoring Symbol.isConcatSpreadable

`Iterator.prototype`, or a shared object to use.

What is the type of this builtin JS value?

Push an array of items into an array, while being robust against prototype modification

quote and parse shell commands

Robustly set the [[Prototype]] of an object

Robustly get an object's own property keys (strings and symbols), including non-enumerables when possible

utility library for parsing asn1 files for use with browserify-sign.

node's assert.deepEqual algorithm

simplified stream construction

deterministic JSON.stringify() with custom sorting to get deterministic hashes from stringified results

traverse and transform objects by visiting every node on a recursive walk

recursively transform key strings to camel-case

return the first argument that is `!== undefined`

return whether two buffers are equal

Look up HTML tag names via HTML Element constructors, and vice versa.

`AsyncIterator.prototype`, or a shared object to use.

Parse a github URL into an object.

Spec-compliant shim for Symbol.prototype.description proposal.

human-readable TAP summarizer

Loosely test a package's compliance with the es-shim API

a PURL ( https://tc54.org/purl/ ) parser and serializer

Returns an arbitrary generator function, or undefined if generator syntax is unsupported.

Turn an array into a list of comma-separated values, appropriate for use in an English sentence.

Sometimes you have to do horrible things, like use the global object to share a singleton. Abstract that away, with this!

code coverage browserify transform

Utility package to determine if an `Array.prototype` method properly boxes the callback's receiver and third argument.

`deep-equal`, but only for JSON-supported values.

ignorefile/includefile matching .gitignore spec

Polyfill/shim for `document.contains`

Polyfill/shim for util.promisify in node versions < v8

[![github actions][actions-image]][actions-url] [![coverage][codecov-image]][codecov-url] [![dependency status][deps-svg]][deps-url] [![dev dependency status][dev-deps-svg]][dev-deps-url] [![License][license-image]][license-url] [![Downloads][downloads-im

Which regular expression flags does the current environment support?

combine two Date objects, "day" and "time", into a new Date object

command-line tool to validate a `.nvmrc` file

write tests for browser code

node library to access the Travis-CI API