@sindresorhus/is
Type check values
Type check values
The assert module from Node.js, for the browser.
String validation and sanitization
A tiny invariant function
A little library for asserting types and values, with zero dependencies.
BDD/TDD assertion library for node.js and the browser. Test framework agnostic.
JavaScript test spies, stubs and mocks.
Better assertions for node, reporting the expr, filename, lineno etc
flow typed nullthrows
Next-gen browser and mobile automation test framework for Node.js
assert with status codes
Validate XML, Parse XML, Build XML without C/C++ based libraries
tap-producing test harness for node and browsers
Function argument validation for humans
test framework agnostic BDD-style assertions
Helper function for exhaustive checks of discriminated unions in TypeScript
Precondition checking utilities.
Utilities to get and check variable types (isString, isPlainObject, isRegExp, etc)
Hook and modify stdout and stderr
Power Assert feature enhancer for assert function/object