JavaScript Interview Questions Series

A simple test-driven structure for practicing JavaScript interview questions.

Structure

Each question has its own directory with a descriptive name:

• questions/question1-promise-all/ - Promise.all() polyfill
• questions/question2-map/ - Array.map() polyfill
• questions/question3-{name}/ - (Future questions)

Each question directory contains:

• index.js - Contains the problem, solution, and tests (all in one runnable file)
• README.md - Problem description and instructions

How to Use

Running a Question

Navigate to the question directory and run:

cd questions/question1-promise-all
node index.js

Or from the root directory:

node questions/question1-promise-all/index.js

This will:

1. Execute the solution code
2. Run all test cases
3. Show ✓ (green) for passing tests
4. Show ✗ (red) for failing tests
5. Display a summary at the end

Example Output

🧪 Running tests for: Question 1: Promise.all() polyfill

──────────────────────────────────────────────────

✓ All promises resolve successfully
✗ One promise rejects
  Error: ...
──────────────────────────────────────────────────

📊 Results: 1 passed, 1 failed

❌ Some tests failed

Adding New Questions

1. Create a new directory: questions/questionN-{problem-name}/
2. Create index.js in that directory
3. Import the TestRunner: const TestRunner = require('../../test-runner');
4. Create a runner instance: const runner = new TestRunner('Question N: Description');
5. Add tests using runner.test('description', async () => { ... })
6. Run tests with runner.run();
7. Optionally add a README.md with problem description

Current Questions

• Question 1: Promise.all() polyfill implementation (questions/question1-promise-all/)
• Question 2: Array.map() polyfill implementation (questions/question2-map/)

Contributing

For YouTube tutorial series - feel free to fork and practice!