What are Code Quality and Code Quality Metrics?

The quality of the code can have a significant impact on the quality of software, program groups' performance, and the ability to collaborate. But how can you measure the quality of code to determine if your system is worth its salt?

This article is about quality metrics. We included usability, code readability, and documentation levels, as well as useful automated quantitative measurements of code quality, such as cyclomatic complexity. You can use any of these indicators to evaluate your current quality level and see if it is improving.

Why Code Quality Matters?

What is quality code? There is no exact definition for this. As a rule, an understanding of what a quality source code should look like is basing on many years of specialist experience. Some programmers adhere to the abstract KISS principle, which stands for Keep It Simple Stupid! In part, this creates a fair method, reflecting the main rule of the right code, like simplicity and clarity. However, simplicity is often confused with simplification, so several more properties judge the source code's quality in a professional environment:

• Perception. The code is not overloading with complex constructions, so it is easy to understand without additional documentation or comments.
• Maintenance. It's easy to make changes to thoughtful code: change configurations or even platforms.
• Expansion. It's easy to add new functionality to it without risking breaking the coding algorithm. Also, if you encounter any problems, they can be quickly fixed.
• Broadcast. The right code can be passing on to other developers for support or refinement, and they will have no difficulty in reading it.
• Test coverage. The higher the percentage of code coverage with tests, the more likely it is to avoid unnecessary bugs in the future.

Each programming language has its Code Style - this is the standard for creating. It is the style of the code that gives us an understanding of the rules for spaces, brackets, line breaks, or variable names. It may seem that this may not be so important, but following the rules will lead to a complete understanding of the code by those who see it for the first time.

Not every developer can write excellent code. It is especially tricky for beginners. Even competent developers make mistakes, so when creating quality software, you need to regularly check the code.

The quality of the code is essential, as it affects the overall quality of the software. And condition affects how secure and reliable your codebase is. High quality is critical to many development teams today. And this is especially important for those who develop security-critical systems.

• Essentially, code that is considered good:
• Does what it should.
• There must be a consistent style.
• It is easy to understand.
• It must be self-documented.
• It cant be checked.

Just testing is not enough. Developers are not perfect. Manual code reviews and testing will never find every error in the code.

The study "Software defect origins and removal methods" showed that individual developers are less than 50% more likely to find errors in their software. And most forms of testing are only 35% effective. I make quality determination difficult.

Encoding errors are at risk. When the code is of poor quality, it can pose a security risk.t In the event of a software failure, the results can be catastrophic or fatal due to a security breach or lack of security.

Quality is everyone's responsibility and everyone's business. Developer. Tester. Manager. High quality should be the goal throughout the development process.

How to Measure Code Quality?

There is no single way to measure the quality of your code. What you are measuring may differ from what the other development team is measuring. But let's take a look at the qualitative and quantitative indicators of code quality that can be measured to improve it:

Code Quality Metrics: Qualitative

Qualitative metrics aim to determine better what is right, mostly subjective.

1. Expansibility
   Expansibility is the degree to which software is encoded to support future growth. The central theme of extensible applications is that developers should be able to add or modify functions to the code without affecting the entire system.
2. Maintainability
   Maintainability of the code is a qualitative measurement of how easy it is to make changes and the risks associated with such changes. Developers can judge the possibility of maintenance when they make changes, for example, if the move takes an hour, but in the end, it takes three days, the code is probably not that good. Another way to measure serviceability is to check the number of code lines in a given software function or an entire application. Software with many lines can be harder to maintain.
3. Readability
   Readable code should be indented and formatted by standards specific to the language in which it is writing; this makes the application structure consistent and visible. Comments should be used where necessary, with brief explanations for each method. Method names should be meaningful in the sense that the names indicate what the way does.
4. Clarity
   Clarity is a measure of quality, which suggests that the right code should be unambiguous. If you look at a piece of code and wonder what it does, then this code is ambiguous. Also, readability and documentation mean that any other developer can easily use code written by someone else without spending much time understanding how it works.
5. Self-documented
   Self-documenting source code follows naming conventions and structured programming that allows you to use it without specialized knowledge. In web development, self-documentation refers to a website that discloses the entire process of its creation through public documentation, and whose public documentation is part of the development process.
6. Well tested
   Well-tested codes are likely to be of higher quality since much more attention is paid to the internal workings of the code and its impact on users. Testing means that the application is continuously under scrutiny.
7. Efficiency
   Useful code uses only those computing resources that it needs. Another measurement of effectiveness is that it is performing in the shortest possible time. For most developers, inefficient code is a low-quality code. Some of the negative consequences of not building to improve efficiency are long build times, difficulty in detecting and fixing bugs, and performance problems for the user.

Code Quality Metrics: Quantitative

There are several quantitative measurements to identify well-written applications:

1. Weighted Micro Functions
   This indicator is a modern software sizing algorithm that analyzes the source code and breaks it into micro functions. The algorithm then generates several complexity metrics from these micro functions before interpolating the results into a single estimate. WMFP automatically measures the complexity of the existing code. Metrics for determining WMFP value include comments, code structure, arithmetic calculations, and flow control path.
2. Halstead Complexity Measures
   Halstead's complexity measures, which introduced in 1977, reflect the vocabulary and length of the program, the volume, and complexity, as well as the estimated number of errors in the module. The purpose of the measurement is to evaluate the computational complexity of the program. The more sophisticated any code, the more difficult it is to maintain and the lower its quality.
3. Cyclomatic Difficulty
   Cyclomatic complexity is an indicator that measures the structural complexity of a program. It is making by counting the number of linearly independent paths through the program source code. If the cyclomatic complexity is greater than 10, then such methods most likely contain defects. It is cyclomatic complexity that will show developers how difficult it will be to test the code and fix bugs. To understand how easy it will be to change the application, this metric can be combining with a size metric.

How to Improve Code Quality?

There are several ways to achieve a high code value; let's take a look.

Code Review is considered a very popular and straightforward technique. It means that changes get into a software release version only after checking by the rest of the team.

This process consists of several stages:

• The developer adds new features to the code and notifies the others that they need to check for these updates.
• At the second stage, team members, or reviewers, look at the code and leave their comments. Some companies that practice Code Review focus only on finding bugs. You also need to point out architectural flaws, misuse of tools, and poor writing style like poorly understood. It helps to improve the quality of the code.
• Further work with remarks follows. If the author does not agree with any claim, he can reject it, but for this, he has to provide convincing arguments in defense of his position. If there are no arguments, he makes the necessary corrections.
• Everything is repeating first and automatically happens whenever a new batch of changes is making to the code.

Functional testing helps the developer focus on the functionality of the software from the beginning, thereby removing extraneous code. The goal of software development is to write an application that provides what users need.

Cleaning requirements. Most software development projects start with requirements documents or story maps in agile development. A project with precise, workable requirements has a much greater chance of achieving high quality than ambiguous, poorly defined requirements.

Quality measurement helps you understand where you are. After the analysis, you can take steps to improve the overall quality, such as using coding standards, analyzing the code before checking the code, following the recommendations for testing the code, refactoring the old code, if necessary.

The Impact of Code Quality Metrics on Business

The most important parts of the code will always be those that affect the profitability of the software. From 40 to 80 percent of the average software, the development budget is spending on software maintenance. The main problem in maintaining the software is understanding the existing code, and this is where code quality indicators can have a significant impact.

Therefore, the quality code should always be easy to understand by readability, formatting, clarity, proper documentation. And easily changeable by maintainability and extensibility.

Moreover, support for systems with good architecture is cheaper. You should always keep in mind that:

• Lack of attention to code quality leads to the accumulation of technical debt.
• Technical debt slows down the development of the system.
• Even professional teams sometimes make bad decisions. But the application of modern practices and the periodic "repayment" of technical debt allows you to keep it under control.
• Maintaining a high level of code quality minimizes technical debt. It is possible to focus on new features and release them with less effort, faster and cheaper.

Martin Fowler also has an article about technical debt.

And in short:

Сompare the extra time spent adding new features with interest on a bank loan. Cleaning technical debt is like paying attention to a mortgage. This metaphor describes the essence well. But it may create a false feeling that technical debt can be managing entirely only. However, in reality, it is much more complicated.

What Tools Does Amoniac Use?

RuboCop

RuboCop is a Ruby static code analyzer (a.k.a. linter) and a code formatter. Out of the box, many of the recommendations outlined in the Ruby Style Guide community can be implementing. Works with all significant Ruby implementations, auto-corrects many detected code violations provides reliable code formatting capabilities. Also, such a tool has a few useful plugins which extend your analysis of code like rubocop-rails or rubocop-rspec.

Reek

Smells are indicators of where your code can be challenging to read, maintain, or develop, rather than something that is precisely incorrect. Naturally, this means that Reek is looking into the future of your code, and, of course, that is what can make its reports somewhat subjective.

Fasterer

Get your Rubies to work faster with this command-line tool inspired by fast-ruby and Spherical's performance at Baruco Conf. Fasterer will offer some speed improvements that you can check in detail in the fast-ruby repository. In no case should blindly follow the advice. Using a while loop instead of each_with_index should probably not be considered if you are working with a regular Rails project. Still, perhaps if you are doing something very speed-dependent, such as Rack, or creating your infrastructure, you might consider this to be an increase in speed.

Summary

Writing quality code is not exhausting. After a couple of iterations, those things that the developers used to follow, become natural, that is, they develop an internal culture. It is only necessary to configure the process correctly. There is no secret that in the beginning, it will take extra time. But soon everything will pay off handsomely.

If any questions appear about this article - contact us directly at hello@amoniac.eu or +372 5400 5270.