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

assert with status codes

minimalistic-assert ===

typesafe assertion library for TypeScript 3.7+

Helper function for exhaustive checks of discriminated unions in TypeScript

Parses, serializes, and manipulates MIME types, according to the WHATWG MIME Sniffing Standard

Synchronous validation of a path existing either as a file or as a directory.

Type check values

correct invalid SPDX expressions

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

Is this value a JS ArrayBuffer?

Extra assertions on top of node's assert module

Which kind of boxed JS primitive is this?

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.

Check if an environment is little endian.

Is this value a JS SharedArrayBuffer?

Is this specifier a node.js core module?

What is the type of this builtin JS value?

Test if a value is an array.

Return a function which tests if every element in an array passes a test condition.