Examine code quality

3 minutes

The quality of code shouldn't be measured subjectively. A developer-writing code would rate the quality of their code high, but that isn't a great way to measure code quality. Different teams may use different definitions based on context.

Code that is considered high quality may mean one thing for an automotive developer. And it may mean another for a web application developer.

The quality of the code is essential, as it impacts the overall software quality.

A study on "Software Defect Origins and Removal Methods" found that individual programmers are less than 50% efficient at finding bugs in their software. And most forms of testing are only 35% efficient. It makes it difficult to determine quality.

There are five key traits to measure for higher quality.

Reliability

Reliability measures the probability that a system will run without failure over a specific period of operation. It relates to the number of defects and availability of the software. Several defects can be measured by running a static analysis tool.

Software availability can be measured using the mean time between failures (MTBF).

Low defect counts are crucial for developing a reliable codebase.

Maintainability

Maintainability measures how easily software can be maintained. It relates to the codebase's size, consistency, structure, and complexity. And ensuring maintainable source code relies on several factors, such as testability and understandability.

You can't use a single metric to ensure maintainability.

Some metrics you may consider to improve maintainability are the number of stylistic warnings and Halstead complexity measures.

Both automation and human reviewers are essential for developing maintainable codebases.

Testability

Testability measures how well the software supports testing efforts. It relies on how well you can control, observe, isolate, and automate testing, among other factors.

Testability can be measured based on how many test cases you need to find potential faults in the system.

The size and complexity of the software can impact testability.

So, applying methods at the code level—such as cyclomatic complexity—can help you improve the testability of the component.

Portability

Portability measures how usable the same software is in different environments. It relates to platform independence.

There isn't a specific measure of portability. But there are several ways you can ensure portable code.

It's essential to regularly test code on different platforms rather than waiting until the end of development.

It's also good to set your compiler warning levels as high as possible and use at least two compilers.

Enforcing a coding standard also helps with portability.

Reusability

Reusability measures whether existing assets—such as code—can be used again.

Assets are more easily reused if they have modularity or loose coupling characteristics.

The number of interdependencies can measure reusability.