Testing Jspreadsheet in Vue.js with Jest: A Comprehensive Guide

Introduction to Vue.js Unit Testing with Jest

Unit testing plays a vital role in modern Vue.js applications to ensure that components function as expected and to prevent any potential regressions. When working with Jspreadsheet and integrating it into Vue.js, it's essential to test this functionality thoroughly. This guide will walk you through the process of setting up unit tests for Jspreadsheet in Vue.js using Jest.

By following this guide, you'll learn how to efficiently integrate and test Jspreadsheet in your Vue.js project, ensuring the reliability and performance of your components.

Vue.js Testing Environment Setup

In this section, we’ll guide you through setting up a Vue.js environment specifically for testing Jspreadsheet using Jest and JSDOM. This will help you create a solid foundation for running unit tests for your Jspreadsheet instances.

Step 1: Clone or Create a Vue.js Project

To begin, you can either clone an existing Vue.js project or create a new one using @vue/cli. Here's how to get started:

vue create jspreadsheet-vue-testing
cd jspreadsheet-vue-testing

Alternatively, clone our setup from GitHub.

Step 2: Install Dependencies

Next, install the necessary dependencies, including jspreadsheet, Jest, and jest-environment-jsdom:

npm install jspreadsheet-ce@5.0.0-beta.3
npm install --save-dev jest@29.7.0 jest-environment-jsdom@29.7.0

Step 3: Configure Jest for Jspreadsheet

To integrate Jspreadsheet properly in a Jest testing environment, you'll need to set up JSDOM. First, create a jest.setup.js file in the root of your project:

// jest.setup.js

const jspreadsheet = require('jspreadsheet-ce');

  // Code that runs before each test
beforeEach(() => {
    if (typeof document !== 'undefined') {
        jspreadsheet.destroyAll();

        if (!global.jspreadsheet && !global.root) {
            global.jspreadsheet = jspreadsheet;

            global.root = document.createElement('div');
            global.root.style.width = '100%';
            global.root.style.height = '100%';

            document.body.appendChild(global.root);
        }
    }
});

Next, configure Jest to use this setup by adding the following entry to your package.json:

{
  "jest": {
    "setupFilesAfterEnv": ["<rootDir>/jest.setup.js"],
  }
}

This configuration ensures JSDOM will emulate the DOM environment required to run Jspreadsheet within Jest.

Step 4: Create a Test

Create a folder inside your project if it doesn't exist, then inside this folder create a file named jspreadsheet.test.js.

// */tests/jspreadsheet.test.js

/**
 * @jest-environment jsdom
 */

test("Testing data", () => {
    let instance = jspreadsheet(root, {
        worksheets: [
            {
                data: [
                    ["Mazda", 2001, 2000],
                    ["Peugeot", 2010, 5000],
                    ["Honda Fit", 2009, 3000],
                    ["Honda CRV", 2010, 6000],
                ],
                minDimensions: [4, 4],
            },
        ],
    });

    expect(instance[0].getValue("A1", true)).toEqual("Mazda");
    expect(instance[0].getValue("A2", true)).toEqual("Peugeot");
    expect(instance[0].getValue("B1", true)).toEqual("2001");
});

This test verifies that a basic Jspreadsheet instance is created and that the data values are correctly placed. You can modify it to check for more specific scenarios as needed.

Running the Tests

Ensure you add the following line to the scripts section of your package.json:

"test": "jest"

After creating your tests and updating package.json, you can run them using the following command:

npm test

Jest will run all the tests in your project and display the results in the console. If everything is configured correctly, your tests should pass.