How to check code quality?

Mykhailo Glodian Mykhailo Glodian / 18 November 2020 4 min read

How to check code quality?

The quality of the code tells whether the code is good or bad. The code quality matters for software quality. A software or an application with good quality of code will be easy to maintain. But on the other side, if the quality of the code is bad it will be difficult to maintain. Bad code quality can also lead to security risks.

A variety of difficulties can be faced if the quality of the code is bad. For example, the developer will face difficulty while adding a new feature to an application with bad code quality because it does not has comments or documentation. Even the code with bad quality also becomes difficult for its own developer.

A code with good quality has different characteristics. Below given diagram shows the characteristics of a code with good quality. The first way to check your code is its characteristics. If your code has these characteristics then it has good quality.

Code quality standards

Reliability:

A code that is having good quality is reliable i.e. it has the ability to perform error-free operations whenever it runs. To make a code reliable it must be tested in every possible way by using the proper exception handling.


Maintainability:

One of the characteristics of a good code is that it is easy to maintain. The developer can add a new feature in less time with fewer efforts. Also adding a new feature does not affect the functionality of the existing code. This can be achieved by using the proper names for classes, methods, and variables and writing the comments with proper formatting of code.


Reusability:

Good quality code must be able to be reused. It means that the same code can be used for another function or software.


Portability:

Portability means the ability of code to be run in different environments. The code with good quality must be run in different environments without any error.


Testability:

The code also needs to be easy to be tested or verified. Less number of test cases should be required to verify it. The presentation and logic need to be separated.


Code Metrics

Code metrics are another way to check the quality of your code. Code metrics are used to analyze the complexity of code and provide better insights to the developer. If the code has more complexity then it has a bad quality otherwise the quality is good. Some of the metrics are given bellows with a detailed description that can be used to quantify the code quality.


WMFP (Weighted Micro Function Points)

This metric is an algorithm that breaks down your code into different micro functions. For each of these micro functions, it produces the complexity metric. In the end, it gives a single score based on these results. The complexity of code is measured automatically by WMFP.


Halstead Complexity Measures

In 1977, Maurice Howard Halstead introduced these measures. It includes different metrics such as the Program length, Program volume, Halstead vocabulary, Program level, Minimum potential volume, Program difficulty, Programming effort, Language level, Intelligence content, Programming time. Measuring computational complexity is its primary aim. A code with less complexity can easily be maintained.


Cyclomatic Complexity

The structural complexity of the code is measured by this metric. Total linearly independent paths are counted for this purpose. Methods having cyclomatic complexity of more than ten probably contains more defects. Cyclomatic complexity tells the developer about the difficulty of code for testing, maintaining, and troubleshooting.

code quality

Code Quality Tools

Different tools are available that can be used to ensure the code has good quality. These tools continuously check the source code to tell the developer about the code quality. Some of the tools are listed below that can be used by the developers.

  • Duecode
  • Crucible
  • SonarQube
  • Upsource
  • Review Board
  • Code Climate
  • Phabricator
  • ESLint
  • Klocwork
  • Codacy
  • Pylint
  • JSHint

Other ways to measure code quality


Code Guidelines:

The code can be checked against the guidelines to check its quality. For example, there are different guidelines to write a good code. It includes proper indentation so that it should be easily readable, there should be proper comments about each method that will help the developer to know about the purpose of each method. It will help in making the changes. If the code follows the guidelines then it has good quality.


Testing:

Another way to check the quality of your code is by testing. The code can be executed against different inputs. If the code performs well against different inputs then it has good quality.


Review:

The code can be reviewed by the developer to find bugs that can be removed to make it a good quality code. One of the common ways is to ask for a review from different developers. If they found more bugs in the code then it has bad quality.


Conclusion

Good quality of the code helps in developing a good application that can easily be maintained and extensible in the future according to the requirements. Another developer can also easily work on a good quality code. So the code should be properly checked for quality through metrics to ensure good quality.