Refactoring

What is Refactoring?

Refactoring is the process of improving the internal structure of existing code without changing its external behaviour. This practice focuses on cleaning up code to make it more readable, efficient, and easier to maintain. It does not directly add new features or fix bugs, but rather prepares the codebase for future development by reducing technical debt. In project management, particularly in software development, refactoring enables teams to manage complexity and prevent long-term issues resulting from poorly written or outdated code.

Project teams can apply this process at any stage of development, but it is most valuable when done on a regular basis. Refactoring is often part of agile workflows, where continuous improvement is encouraged. Development teams usually use automated testing to ensure their code still functions correctly after they’ve made changes.

Key Points

• Refactoring improves code quality without changing its output or functionality.
• It makes the codebase easier to understand, maintain, and extend.
• This process is often performed in small, controlled steps to reduce risk.
• Refactoring relies on a strong suite of automated tests to confirm behaviour remains unchanged.
• It supports long-term productivity by addressing technical debt and preventing software rot.

Related Terms

• The concept of technical debt helps explain the trade-offs that necessitate refactoring over time.
• Code review often identifies areas that require refactoring through peer feedback and shared standards.
• Continuous integration enables safe refactoring by running automated tests each time code is updated.
• The use of unit testing ensures individual components behave as expected before and after changes.
• Agile methodology encourages regular refactoring as part of ongoing iteration and code improvement.

Refactoring: Example

A software team maintains a web application where a function used to calculate taxes appears in multiple places. Instead of rewriting it each time, a developer refactors the code by extracting this logic into a single, reusable function. This reduces duplication and makes future updates easier. The application’s behaviour remains the same, but the code becomes more efficient and maintainable.

Refactoring: Best Practices

• Always run tests before and after refactoring to confirm code behaviour stays the same.
• Break down refactoring tasks into small, manageable steps to reduce complexity and risk.
• Maintain regular communication within the team to ensure shared understanding of changes.
• Use version control tools to track changes and roll back if needed.
• Schedule time for refactoring as part of regular development cycles, not just when problems arise.

Additional Resources

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