A compact testing module for node.js.

Usage no npm install needed!

<script type="module">
  import testjs from 'https://cdn.skypack.dev/testjs';



test.js is a compact testing module for node.js that simply wraps node's assert module and generates pretty printed output.

  • Small footprint, minimal dependencies
  • Non-utf8 and Windows terminal approved
  • Allows asynchronous testing
  • Allows modular tests by just assembling data structures
  • Simple API and Cli (just testjs)
  • Emphasis on timers
  • Available through npm: npm -g install testjs




Place your test suite in tests/suite.js.

// package.json
    "devDependencies": {
        "testjs": "latest"
    "scripts": {
        "test": "testjs"

npm test


// tests/run.js
var Suite = require("testjs");

    "firsttest": function(test) {
// package.json
    "scripts": {
        "test": "node tests/run.js"

npm test


All of node's assert (just replace assert through test) plus test.notOk(...) as a negated ok.

  • test#ok(actual) / test#notOk(actual) / test#ifError(actual)
  • test#equal(actual, expected) / test#notEqual(actual, notExpected)
  • test#deepEqual(actual, expected) / test#notDeepEqual(actual, notExpected)
  • test#strictEqual(actual, expected) / test#notStrictEqual(actual, notExpected)
  • test#throws(blockFunction[, classRegExpOrValidationFunction]) / test#doesNotThrow(blockFunction)

There is also a test#log(...) for logging straight to the test console.

Self-explaining examples

When typing testjs in a terminal, tests/suite.js will be run. Also supports running runners: testjs tests/run.js or custom / other unit tests under the condition that the runner (here: run.js) does not export anything. If it does, whatever it exports will be run.


test.js is partially interoperable with nodeunit. There is no setUp/tearDown however and there are no aliases for things like equal, which is for example aliased as equals in nodeunit. However, test.js including dependencies is about 100kb while nodeunit is about 16mb.

Command line options

Option Function
--nocolors or -nc Disables terminal colors.
--name=NAME or -n=NAME Sets the suite name. Defaults to the name defined in package.json which is looked up inside of the current working directory or to the base name of the suite file if there is no package.json. The hard coded default is suite.
--silent or -s Does not produce any output.

Always returns the number of failed tests as the status code.

Example: testjs --name=MyGame -nc tests/mygame-test.js


Apache License, Version 2.0