How do I start the Supermarket Receipt refactoring kata?

Clone the GitHub repository and check out the 'with_tests' branch to begin with pre-written tests, or start from scratch to practice test creation and refactoring incrementally.

What code smells should I look for in this kata?

Focus on Long Method and Feature Envy as mentioned in the README, and apply refactorings like method extraction or moving methods to improve object-oriented design.

How to implement the HTML receipt feature?

Create a new method or class to generate HTML output while minimizing duplication with the existing text receipt, ensuring all data and formatting remain consistent as described.

Supermarket Receipt kata vs Gilded Rose: which is better for refactoring?

Supermarket Receipt focuses on pricing logic and discounts, while Gilded Rose deals with inventory aging; choose based on interest in retail or game-like domains for varied practice.

Can I use this kata for team training sessions?

Yes, it's designed for learning hours and integrates with coaching methods like Samman, making it effective for pair programming, coding dojos, and structured workshops.

What programming language is the kata written in?

The original implementation is in Java, but community ports exist for other languages; check the repository for specific versions or adapt the logic to your preferred language.

Open-Awesome

SupermarketReceipt Refactoring Kata

MITC#

A refactoring kata for practicing test-driven development and code improvement on a supermarket receipt system.

Visit Website GitHub

130 stars361 forks0 contributors

What is SupermarketReceipt Refactoring Kata?

Supermarket Receipt Refactoring Kata is a coding exercise that provides a legacy codebase for practicing refactoring and test-driven development. It simulates a supermarket receipt system with pricing, discounts, and special offers, allowing developers to improve their skills by identifying code smells, writing tests, and implementing new features.

Target Audience

Software developers, coding bootcamp participants, and teams looking to practice refactoring, test-driven development, and clean code principles in a structured exercise.

Value Proposition

It offers a realistic, self-contained codebase with intentional flaws, enabling focused practice on refactoring techniques without the overhead of setting up a project from scratch, and integrates with coaching methods like Samman for guided learning.

Overview

This is a refactoring kata for improving your coding skills

Use Cases

Best For

Practicing test-driven development on legacy code
Learning to identify and refactor common code smells
Conducting coding dojos or learning hours with teams
Improving skills in incremental code improvement
Preparing for technical interviews focusing on refactoring
Teaching clean code principles in workshops

Not Ideal For

Teams building a production-ready supermarket POS system requiring scalability and real-time features
Developers seeking to learn a new programming language through full project implementation with modern frameworks
Projects needing immediate deployment with minimal refactoring overhead, such as hackathons or rapid prototypes

Pros & Cons

Pros

Realistic Code Smells

Includes intentional flaws like Long Method and Feature Envy, providing tangible targets for refactoring practice as highlighted in the README's code smell identification.

TDD Encouragement

Explicitly prompts writing automated tests before refactoring to ensure code safety, aligning with test-driven development principles as described in the feature set.

Structured Learning Integration

Supports the Samman coaching method for organized learning hours, making it ideal for team workshops and coding dojos, as noted in the README.

Feature Implementation Practice

Offers new feature requests like discounted bundles and HTML receipts, allowing developers to apply refactoring skills to real-world scenarios beyond basic exercises.

Cons

No Production Readiness

The codebase is designed as an exercise and lacks essential elements like error handling, database persistence, or API endpoints, making it unsuitable for real applications.

Limited Beginner Guidance

Assumes prior knowledge of refactoring techniques and TDD, with minimal step-by-step instructions, which can be challenging for novices without external resources.

No Reference Solutions

Does not include answer keys or validated implementations, potentially leading to frustration for learners who need feedback on their refactoring choices.

Frequently Asked Questions

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