Most application developers and testers eventually come across code smells, especially when working with complicated applications or across big teams. These are physical and observable signs that something is wrong with an application’s core code, which could lead to significant failures and ruin the app’s performance.
Inefficient, non-performant, complex, and difficult to update and maintain code is especially “smelly.” While code smells may not always indicate a significant problem, pursuing them often leads to discovering lower-quality code, resource drains, or even critical security flaws in the application’s code. At the very least, it requires teams to run in-depth tests on the code, which frequently shows some crucial places requiring attention.
What Does Code Smell Mean?
A code scent is a defect in source code that isn’t a bug or precisely incorrect technically. The code will still compile and function normally. However, it implies a breach of design principles, leading to future issues.
Duplicate code, for example, that was copied and pasted in numerous locations in the source code rather than writing one method and referring it from each of those places is a clear breach of good coding principles. Some code odors are less obvious, but they signal that programmers are cutting corners and not investing in quality code.
According to Martin Fowler, code smells aren’t a problem in and of itself. Instead, they are red flags suggesting the code may have a severe flaw. Long functions, for example, are seen as a code smell; however, not all long functions are bad or badly conceived. According to Fowler, junior members of a development team should notice code smells and review them with senior members, who can determine whether the code has a deeper problem.
The following are some examples of code smells:
- Code duplication
- Unused code
- Lengthy procedures
- A long list of parameters
- Comments
- Basic variables that aren’t needed
- Clusters of data
How to Solve Code Smell—Code Refactoring to the Rescue
Kent Beck defines refactoring as:
“A change to a system that does not affect its behavior but improves non-functional qualities such as simplicity, adaptability, and performance.”
According to Martin Fowler, it is:
“A modification to software’s internal structure makes it easier to understand and modify without affecting its observable behavior.”
Refactoring has no monetary value because it does not change the functionality, features, or code. But on the other hand, a continuous reworking of code prevents “design decay,” cleans up and improves the quality of the code, and makes it far more readable, manageable, and bug-free over time.
Refactoring eliminates code smells, but it’s also about maintaining source code as a living system, just as any complicated system requires regular maintenance to be healthy.
The Refactoring Flow
To refactor code that has quality issues, apply the following procedure:
- First, make sure all tests pass –Fix any code parts that cause the build to fail first.
- Look for code smells –Code that works but has issues like discussed before in this piece. Of course, code smells vary based on context, environment, and language.
- Determine simplification –Understand what should be changed in the code to reduce repetition and complexity.
- Use simplification –Change the code to eliminate the odor.
- Double-check that all tests pass –refactoring code is often complicated, and numerous dependencies must be considered. In addition, because refactoring frequently breaks old code, it’s critical to ensure that everything functions as intended following the change.
Where to Start? Quality Intelligence Marks the Spot
Often, development teams are at a loss when they become aware of code smells, code quality, and the significance of refactoring, or inherit legacy code that does not correspond to their standards. It is difficult to prioritize code smells and understand their true influence on system performance, maintainability, and the risk of defects in production.
Fortunately, a new technology category known as Quality Intelligence Platforms is emerging. Quality intelligence can detect code at the risk of quality concerns by evaluating how frequently code is modified and tested thoroughly.
When starting a refactoring project, start with the most dangerous code. That’s where restructuring is most likely to improve the end user’s perception of quality. Quality intelligence can assist you in incorporating code quality information into your agile operations in the following ways:
- You can focus maintenance and bug fixes on code at high risk of quality concerns in sprint planning.
- Sprint retrospectives allow you to examine code written during the sprint, identify quality concerns, and assess your technical debt.
Techniques for refactoring code smells
Refactoring is a term that refers to a set of code hygiene techniques. However, when it comes to removing code smells, three ways are very effective: one that focuses on methods, another on method calls, and a third on classes.
Methods of composition
Composing is the first way, and it seeks to eliminate unnecessary techniques. There are two ways for developers to accomplish this:
- The code is divided into smaller chunks. After that, fragmented code is segregated, removed, and placed in its method.
- Broken or superfluous methods, as well as the calls to those methods, are discovered. Finally, the original method is erased, and the method’s actual code replaces the method calls.
Method calls simplified
Next, simplify method calls that have become buried in big pieces of code that are difficult to work with over time. Method calls can be simplified in several ways, including the following:
- Modifying or deleting settings;
- Renaming ambiguous-named methods;
- Separate the querying and changing components;
- Adding parameter objects and parameterizing procedures
- Eliminating methods that assign values to objects; and
- Explicit methods or calls in place of the parameter.
Abstraction-based refactoring
Finally, when big parts of code have duplications or redundancies, abstraction refactoring comes into play. This strategy consists of two techniques, both of which focus on class inheritance:
- Pull up. A superclass contains the code for methods that are shared by a large number of subclasses.
- Apply downward pressure. Method code that sits in a superclass but is only used by a few subclasses is pushed down to the subclasses that need it.
Refactoring and the role of testers
Before you start restructuring, make sure your code is testable. This covers unit tests, regression tests, and integration tests. To this aim, involving the testing team in the refactoring process is beneficial, as tests may fail once development teams begin to update the code. When refactoring, regression testing is crucial because it ensures that the application’s functionality is preserved.
Conclusion,
Refactoring should be done regularly, and it must be done collaboratively. For example, software teams from Java Assignment Help services can build centralized ways to discover code smells and learn from mistakes by regularly conducting code hygiene chores. Learning about the code reorganization process is also beneficial for testers because it can help them improve existing test cases and processes. This could even assist them in writing better test automation code and reducing manual maintenance.
