Python For Engineers

Day 30: Capstone Project — Personal Finance Tracker 1. Learning Objectives By the end of this lesson, you will be able to: Integrate all 29 days of JavaScript knowledge into a single, production-quality application Build a complete CRUD application with persistent data storage Implement client-side routing, data validation, and error handling Use classes, modules, and design patterns for clean architecture Write and run unit tests for core business logic Deploy a finished web application 2. Theory — Full Course Recap Course Roadmap Week Topics Days Week 1 Fundamentals: Variables, Data Types, Operators, Strings, Numbers, Conditionals, Loops, Functions 1–7 Week 2 Intermediate: Arrays, Objects, Destructuring, Closures, HOFs, Error Handling 8–14 Week 3 Browser APIs: DOM, Events, Forms, Storage, JSON, Fetch, Async 15–21 Week 4 Advanced: Classes, Prototypes, Modules, Generators, Event Loop, Performance, Design Patterns, Testing 22–29 Capstone Requirements Your final pro...

Day 29: Testing with Jest 1. Learning Objectives By the end of this lesson, you will be able to: Understand the importance of automated testing in software development Set up Jest in a JavaScript project Write and run unit tests using test() and expect() Use Jest matchers for assertions ( toBe , toEqual , toContain , toThrow , etc.) Group related tests using describe() blocks Test asynchronous code (callbacks, Promises, async/await) Create and use mock functions with jest.fn() Mock entire modules with jest.mock() Apply Test-Driven Development (TDD) basics: Red-Green-Refactor Organize tests effectively for real-world projects 2. Theory Why Test? Automated testing is essential for: Catching bugs early — before they reach production Refactoring with confidence — tests verify behavior doesn't break Documenting behavior — tests show how code is expected to work Preventing regressions — changes don't break existing features Improving design — testable...