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    0.2.3 • Public • Published

    gubb · 🍓 · GitHub license npm version Actions Status

    A very minimalistic Node.js test runner.


    Install the package with npm (or yarn)

    npm install gubb --save-dev

    Getting started

    Defining your tests

    To get started, add your first test file to the project. A test file is a javascript file, containing calls to test and assert. In this example, the file test.js is added to the root of the project.

    With ESM (recommended)

    Import the named exports of gubb like so:

    import { test, assert } from 'gubb';

    Then add your test cases.

    // test.js
    import { test, assert } from 'gubb';
    function myFunction() {
      return true;
    test('my first test', () => {
      const result = myFunction();
      assert('that it returns true', () => {
        return result === true;

    Running your tests

    To run your test, add a test entry to the scripts section of your package.json

      "name": "my-package",
      "version": "1.0.0",
      "type": "module",
      "scripts": {
        "test": "node test.js"
      "devDependencies": {
        "esm": "*"

    Now you can run your test suite on the command-line or in CI with

    npm test

    Node with --experimental-modules flag

    When using the native ES module loader from node, [named exports are not available for node<12](TODO: ADD LINK)

    import * as gubb from 'gubb';
    const { test, assert } = gubb.default;
    // Tests go here

    Node, legacy

    const { test, assert } = require('gubb');
    // Tests go here


    gubb exports two functions: test and assert.


    -- The test function is used to group assertions into a test.

    Syntax: test(testName: String, testFunction: Function)


    test('myFunction', () => {
      // Assertions go here


    assert is used to make assertions.

    Syntax: assert(description: String, conditionFunction: Function)

    assert takes two parameters: a description and a condition function.


    test('isNotFriday', () => {
      assert(() => {
        const isFriday = new Date().getDay() === 5;
        return isFriday;

    The condition function is the function that tests your code. In here, you add logic that assures that your code runs properly. This function should return a boolean, whether the test passed. Alternatively, if the function throws an error, the test is considered failed. If you want to throw inside this function without failing the test, use a try/catch block.


    This project was bootstrapped with TSDX.

    Local Development

    Below is a list of commands you will probably find useful.

    npm start or yarn start

    Runs the project in development/watch mode. Your project will be rebuilt upon changes. TSDX has a special logger for you convenience. Error messages are pretty printed and formatted for compatibility VS Code's Problems tab.

    Your library will be rebuilt if you make edits.

    npm run build or yarn build

    Bundles the package to the dist folder. The package is optimized and bundled with Rollup into multiple formats (CommonJS, UMD, and ES Module).

    npm test or yarn test

    Runs the test watcher (Jest) in an interactive mode. By default, runs tests related to files changed since the last commit.

    Inspired by this tweet by @ryanflorence




    npm i gubb

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