How to Use Test Coverage for Business Profitability

A finished product requires verification before being handed over to the customer or presented to an audience.

There are different types of product testing. In this article, we will talk about them and explain which ones a business should require from a contractor.

What is it?

Test coverage is a metric that determines the scope of different types of tests. During this process, you can get information about the health of the application and the state of the code.

Typically, test coverage is only able to assess 70-80% of the totality of a particular project. The purpose of testing depends on the economics of the goal and the overall risk assessment. Full coverage is usually impractical.

Other factors that are taken into account when testing:

Estimating the cost of project failure, including based on the scope;
The technical documentation of the project should be as clear as possible so that QA can clearly evaluate the test results;
Take into account any special test conditions;
Tests for unexpected errors lost between layers of code.

Testing From the Technical View

There are different types of testing that different specialists are responsible for.

Unit and integration tests are most often carried out by developers or automation QA.

Manual testers are engaged in either intermediate checks at the integration stages or individual endpoints that are checked through postmen. As for acceptance testing, project managers and/or business analysts are engaged in it.

Testing types:

Unit testing: In this case, testing (methods, classes, functions) takes place. Testing, in this case, is easier and faster since you do not need to take into account the dependencies between modules and run the entire application completely. Often during such testing, module dependencies are replaced or mocking.
Integration testing: At this stage, the communication between the modules and the general functioning of the code are checked using software tools. This is a longer process.
System testing: This can be done either manually or automated, for example, using the Selenium tool. Here the reliability of the system as a whole is tested.
Mutation testing (or a / b testing): This helps to assess the quality of previously written tests. In this case, testing of the changed section of the code should end in failure. Mutation testing is commonly used when writing frameworks and libraries.
TDD (Test Driven Development): A special approach to testing, when unit tests are first written, and only after that the modules themselves are compiled. This takes into account all business requirements. The result is a simple transparent code that meets the customer's requirements.

First of all, it is important to understand that testing helps to find and fix bugs and potential problems even before the application is presented to the public.

Improving the quality of the code can also be achieved using static code analyzers.

Code coverage has different assessment criteria:

statement coverage - whether each line of source code has been executed and tested;
condition coverage - whether each decision point (evaluating whether an expression is true or false) has been executed and tested;
path coverage - whether all possible paths through a given part of the code have been completed and tested;
function coverage - whether each program function has been executed;
I / O coverage - whether all function calls and returns have been made.
сoverage of parameter values - whether all typical and boundary parameter values have been checked.

Code Testing Tools to use

As test automation is becoming more and more popular, there are a huge number of tools for automating the process today.

The tools used depend not only on the objectives of the test, but also on the language. Let's take a look at several popular tools and their applications.

Selenium. Popular with testers and web developers. It is one of the best tools out there, and is relevant for projects in JavaScript, Java, Ruby, Python, PHP and C #, and so on.
Appium. Great for testing native, cross-platform and web applications. Great for Android and iOS apps.
Cucumber. A tool that shows test coverage and collects test metrics. Previously worked only in Ruby, today it is used in JavaScript, Java, PHP.

Speaking about PHP directly, as the main language using which projects are created in TopDevs, here the main tool is PHPUnit extensions, as well as various libraries created on its basis.

The Laravel framework also helps here, which offers add-ons to PHPUnit for simpler and faster tests.

So, there is an add-on "DatabaseTransactions trait", which wraps all database queries in transactions and rolls back those transactions upon completion of the test.

This way, you can use the existing data and not damage the current database. You no longer need to create an additional database for testing.

When it comes to testing JavaScript code, the Jest and Mocha libraries are most often used here.

Why do Businesses Need Testing?

User loyalty can lose a lot of points, even with one button not working. Avoiding such punctures can only be done with due regard for testing the product before release.

There are three test levels that determine the quality of the final product: code level, feature level, and application level.

Testing should be agreed with the development team, which will check the correct operation of the application after the completion of development.

Before starting work, it is important to define business goals and technical documentation that will help improve the quality of testing, since there will be a clear understanding of what is expected and what is obtained from certain interactions with the application.

High-quality test coverage provides the following advantages:

the formation of a loyal community;
saving resources on fixing bugs and constant improvements to the application;
reduction of reputational risks;
competitive superiority;
easy app store placement;
no security risks for customers.

It should be understood that test coverage is not only working navigation, but also the correct processing of requests and, for example, transactions.

By using the application, the user implies ensuring the security of his data and uninterrupted operation. Only if the tests are covered at least 60%, the developers can guarantee all this.

Final words

Today, the development process is becoming more and more systematic. Measuring the effectiveness and completeness of testing is the best way to do this.

Test coverage can provide product quality assurance, increasing the profitability of the final product.

Refusal to test is an irrational decision that can harm your reputation, because even after correcting all the shortcomings, it is quite difficult to regain the user's trust.