Tips for improving your refactoring practice

By incorporating these tips into your daily workflow, you’ll not only develop a habit of refactoring but also gain the skills to recognise when and where refactoring is needed. These practices will help ensure that your code remains clean, maintainable, and adaptable over time.

Learn to Spot Code Smells

Familiarise yourself with common code smells — indicators that something might be wrong with your code. Examples include long methods, large classes, duplicate code, overly complex conditional logic, and many parameters in a method.

Whenever you encounter these issues, consider refactoring as a solution to simplify and improve the code structure.
Refactor Small, Frequent Changes

Refactoring doesn’t always mean large-scale changes. Get in the habit of making small, incremental improvements whenever you touch code.

Each time you work on a feature or fix a bug, look for small opportunities to refactor, such as renaming variables, extracting methods, or reducing duplication.
Apply the Boy Scout Rule

Leave the code cleaner than you found it. Even if you didn’t write the code originally, improve it when you come across something unclear or messy.

When working on a feature or bug, take a moment to refactor parts of the codebase that are confusing or poorly structured, without changing its functionality.
Avoid Over-Engineering

Refactoring is about simplifying and improving existing code, not making it more complex. Don’t over-engineer your solutions in an attempt to make the code “perfect.”

Focus on clarity and simplicity. Use the KISS principle (Keep It Simple, Stupid) to guide your refactoring efforts. Always ask yourself, “Can I make this code easier to understand?”
Refactor When Adding New Features

Before adding a new feature, examine the existing code to see if it’s in good condition. If the code is difficult to extend or modify, refactor it first to make your work easier.

Identify areas where you can apply refactoring techniques like Extract Class or Move Method before implementing new functionality. This will prevent new code from being built on a fragile foundation.

Practice Continuous Refactoring

Refactoring should be a continuous practice, not a one-off activity. Integrate it into your daily development routine.

Set aside time in your workflow to review the code you’ve written or touched for possible improvements. Use refactoring as a daily habit rather than waiting for a major overhaul.

Use Automated Tools

Leverage IDE features or tools (such as ReSharper, SonarLint, or CodeMaid) that can help identify areas for refactoring and suggest improvements.

Run static analysis tools regularly to check for code smells, duplication, and inefficiencies, and use them as a guide to refactor consistently.
Use Code Reviews as Learning Opportunities

Participate actively in code reviews, both as a reviewer and a contributor. Reviews can highlight areas where refactoring can improve code quality.

When receiving feedback, look for suggestions related to code readability, duplication, or complexity, and use these opportunities to refactor your code. As a reviewer, point out refactoring opportunities when reviewing others’ code.
Follow the DRY Principle

Follow the DRY (Don’t Repeat Yourself) principle. If you find yourself writing the same or very similar code in multiple places, it’s a sign you need to refactor.

Refactor by extracting common logic into reusable methods or classes to avoid duplication and make the code easier to maintain.
Refactor After Passing Tests

Refactor only after your code is functionally correct and all tests are passing. This ensures that your refactoring does not introduce new bugs.

Write or run tests for your code before refactoring. Once everything works as expected, refactor to improve the code without changing its functionality. This ensures that your refactoring maintains the intended behaviour.
Pay Attention to Method Size

Methods that are too long or do multiple things often need refactoring. Shorter, focused methods are easier to test, understand, and maintain.

Break down long methods into smaller, more focused ones, each with a single responsibility. This will improve code clarity and make your code easier to debug and extend.
Use Design Patterns Thoughtfully

Refactor complex conditional logic or repetitive code using design patterns where appropriate, such as Strategy, Observer, or Factory Method. These patterns often help simplify and standardise solutions to common design problems.

When you see a pattern of behaviour or logic in your code, consider whether a design pattern could help simplify the code and make it more reusable.
Refactor to Improve Readability

Code should be written in a way that is easy to understand, not just for you, but for others as well. Readability is key to maintainability.

If you struggle to understand a piece of code you wrote weeks ago, or if it takes too long to explain it to a colleague, it’s time to refactor for clarity. Simple actions like renaming variables or reorganising logic can have a big impact.
Use Testing to Safeguard Refactoring

Testing is a safety net for refactoring. Write comprehensive unit tests before refactoring to ensure that the behaviour remains consistent after changes.

Once you have written tests, refactor confidently knowing that the tests will catch any unintended changes in behaviour. Always rerun tests after refactoring to ensure nothing breaks.
Refactor Legacy Code Incrementally

Working on legacy code can be daunting, but don’t try to refactor everything at once. Make small, incremental changes over time.

Focus on refactoring small, manageable portions of the legacy code every time you work on it. Over time, these improvements will significantly enhance the code’s quality without disrupting ongoing development.