Vite TypeScript & Jest with Absolute Paths

Introduction:
When working with Vite, TypeScript, and Jest, setting up absolute paths for module imports can enhance code organization and improve developer productivity. However, configuring absolute paths in this setup can sometimes be challenging. In this blog post, we will explore the steps to enable absolute path imports in a Vite project that uses TypeScript and Jest. We'll cover the necessary configurations and potential solutions to address common issues that may arise during the process.

Table of Contents:

1.The Challenge Faced
2.Setting up Absolute Paths in Vite
2.1. Install vite-tsconfig-paths
2.2. Configuring vite.config.js
2.3. Verifying TypeScript Configuration
3.Testing with Jest
3.1. Configuring Jest for Absolute Paths

1. The challenge faced

When working with a Vite project using TypeScript, absolute paths allow us to import modules without worrying about the relative path from the current file. This can improve readability, simplify imports, and make code more maintainable. However, configuring absolute paths in the Vite environment, especially when also using Jest for testing, can present challenges due to different module resolution mechanisms.

2. Setting up Absolute Paths in Vite

To enable absolute path imports in Vite, we need to configure the project appropriately. Here are the steps to follow:

2.1. Install `vite-tsconfig-paths`

npm install --save-dev vite-tsconfig-paths
# or
yarn add --dev vite-tsconfig-paths

2.2. Configuring `vite.config.js`

In the Vite project's root directory, locate the vite.config.js file (create one if it doesn't exist). Update the file as follows:

// vite.config.js
import { defineConfig } from 'vite';
import react from '@vitejs/plugin-react';
import viteTsconfigPaths from 'vite-tsconfig-paths';
// https://vitejs.dev/config/
export default defineConfig({
  plugins: [react(), viteTsconfigPaths()],
});

2.3. Verifying TypeScript Configuration

Make sure your TypeScript configuration (tsconfig.json) includes the necessary options for absolute path resolution:

{
  "compilerOptions": {
    "baseUrl": "./src",
  }
}

Ensure the values correspond to your project's directory structure.

3. Testing with Jest

To ensure Jest recognizes and resolves absolute paths, follow these steps:

3.1. Configuring Jest for Absolute Paths

In your Jest configuration file (jest.config.js or jest.config.ts), make the following updates:

// jest.config.js
/** @type {import('ts-jest').JestConfigWithTsJest} */
module.exports = {
  preset: 'ts-jest',
  testEnvironment: 'jsdom',
  setupFilesAfterEnv: ['@testing-library/jest-dom/extend-expect'],
  moduleDirectories: ['node_modules', 'src'],
};