Espresso (espresso-runner npm)

A lightweight testing framework for JavaScript applications (CLI + Web).

Description

Espresso is a minimal and intuitive, powerful JavaScript testing framework built from scratch. It provides an easy way to write and run tests in your JavaScript projects with zero configuration, offering a simple syntax inspired by popular testing frameworks. This library is designed to keep the testing process lean and efficient while adding a bit of style to your console output.

Key Features

• Simple syntax for writing tests with it and beforeEach.
• Colorful and expressive test output using chalk.
• Supports both DOM-based tests (via jsdom) and regular function tests.
• Lightweight and minimal dependencies.
• Flexible enough to integrate into any project.

Installation

To install cols-espresso as a dependency on the machine, run:

$ sudo npm install -g espresso-runner

Usage

Once installed, you can add tests to your project by creating .test.js files. To run these tests, simply invoke the espresso command in your project root.

$ espresso
OR
$ esp

Writing a Test

Here's an example of a test using cols-espresso:

const assert = require('assert');

let numbers;
beforeEach(() => {
  numbers = [2, 4, 6, 8];
});

it('should return thrice the array', () => {
  const result = numbers.map((value) => value * 3);
  assert.deepStrictEqual(result, [6, 12, 18, 24]);
});

Running Tests

Once you've written your tests in files that end with .test.js, run the following command from the root of your project to execute all tests:

espresso

You’ll see a colorful output that provides clear feedback about passed or failed tests.

Example Test Output

Running ESPRESSO 🔥 on map.test.js
  ✔ Test Passed - should return thrice the array
  ✔ Test Passed - beforeEach is ran each time

Running ESPRESSO 🔥 on forEach.test.js
  ✔ Test Passed - should sum an array
  ✔ Test Passed - beforeEach is ran each time

DOM Testing Example

With cols-espresso, you can also write DOM tests using jsdom:

const assert = require('assert');
const render = require('./render'); // Assuming you have a render function

it('has a text input', async () => {
  const dom = await render('index.html');
  const input = dom.window.document.querySelector('input');
  assert(input);
});

it('shows a success message with a valid email', async () => {
  const dom = await render('index.html');
  const input = dom.window.document.querySelector('input');
  input.value = '[email protected]';

  dom.window.document
    .querySelector('form')
    .dispatchEvent(new dom.window.Event('submit'));

  const h1 = dom.window.document.querySelector('h1');
  assert.strictEqual(h1.innerHTML, 'AWESOME 🔥');
});

License

The Espresso project is licensed under the MIT License. See the [LICENSE] file for more information.

Screenshoots

espresso runner - testFn fails the test

espresso runner - testFn passed the test

espresso runner - testWeb failed the test returning different message upon correct email

espresso runner - testWeb failed the test returning different message upon incorrect email

espresso runner - testWeb passed the test