Assertion

Assertion Library for Browser and Node.JS

Error constructor for test and validation frameworks that implements standardized AssertionError specification.

Format errors to display a diff between the actual and expected

Allow parsing of the module assertion attributes in the import statement

Support for import assertions in acorn

Pass two numbers, get a regex-compatible source string for matching ranges. Validated against more than 2.78 million test assertions.

Extra assertions on top of node's assert module

Validate XML, Parse XML, Build XML without C/C++ based libraries

minimalistic-assert ===

Type check values

BDD/TDD assertion library for node.js and the browser. Test framework agnostic.

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

A tiny invariant function

String validation and sanitization

simple, flexible, fun test framework

JavaScript test spies, stubs and mocks.

Lazy assertions without performance penalty

flow typed nullthrows

Featherweight assert module

TypeScript implementation of invariant(condition, message)

A little library for asserting types and values, with zero dependencies.

Yet another JavaScript assertion/invariant library.

Do things in development and nothing otherwise

assertion renderer for power-assert context

typesafe assertion library for TypeScript 3.7+

uvu is an extremely fast and lightweight test runner for Node.js and the browser

assert with status codes

Adaptation of react-addons-shallow-compare, for independent usage

JavaScript Testing utilities for React

TypeScript definitions for http-assert

test framework agnostic BDD-style assertions

Extends Chai with assertions about promises.

Hook and modify stdout and stderr

A simple and composable way to validate data in JavaScript (and TypeScript).

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Additional Jest matchers

Next-gen browser and mobile automation test framework for Node.js

Helper function for exhaustive checks of discriminated unions in TypeScript

Better assertions for node, reporting the expr, filename, lineno etc

Type assertions aka less-broken `typeof`

JavaScript Testing utilities for React

JavaScript Testing utilities for React

Extends Chai with assertions for the Sinon.JS mocking framework.

Function argument validation for humans

Serenity/JS universal assertion library supporting all types of functional tests, including both web and REST API scenarios

WebdriverIO Assertion Library

Check two valid geojson geometries for equality.

Precondition checking utilities.

A tiny javascript type testing tool

tap-producing test harness for node and browsers