There are several processes by which a testing strategy can go in the wrong way, and one of the most simple is not testing all of the parts which need testing. By measuring and improving the project’s test coverage, you can fight this problem easily. Test coverage is a measure of how well the existing test can protect your applications against regressions.
Here we will cover the main benefits of test coverage and its best strategy to ensure test coverage. We give tips to ensure your application before parting ways with some final considerations.
What is Test Coverage?
Test coverage is defined as a metric in Software Testing, which enables treasure the amount of testing performed by a set of tests. Test coverage includes gathering of information about which parts of a program are executed while performing the test suite to determine which branches of conditional statements are taken.
To put it merely, test coverage is a technique to make sure that the tests are testing the code or how much of the code is exercised by running the test. Test coverage is a metric which ensures to measure how much testing is being performed by the test suite. Consider it as a technique to make sure that all parts of the application are being exercised by running the tests.
Just suppose that your mobile application development has 50 features and they only exercise 37 of them while running the tests then it is said that tests cover 74 per cent of the application.
One of the essential characteristics of test coverage is that you can consider it a black-box technique. Test coverage is more of a high-level approach and concerns itself with features and requirements instead of implementation details.
What Test Coverage does?
- Test coverage ensures to find the area of a requirement which is not implemented by a set of the test cases.
- Test coverage helps to make additional test cases to increase range.
- Test coverage ensures to identify a quantitative measure of test coverage which is an indirect process for quality check.
- Test coverage identifies meaningless test cases which do not increase range.
How can Test Coverage be accomplished?
- Test coverage is done by exercising the static review techniques such as peer reviews, inspections and walkthrough.
- Test coverage can be accomplished by transforming the ad-hoc defects into the executable test cases.
- It can be accomplished at the code level or unit test level. Test coverage can be achieved by availing the automated code coverage or unit test coverage tools.
- With the help of proper test management tools, functional test coverage can be done.
The Benefits of Test Coverage:
Test coverage analyses frequently can inform the test strategy. By understanding the features which are covered helps to assess risks.
Test coverage benefits are-
- The test coverage identifies the gaps in testing. The main benefits of test coverage are that it enables users to identify areas of the application, which are not covered by the current test cases.
- Test coverage assesses the quality of existing tests. By having a high number of test cases and a large area of the application, untested indicates that the test cases are not well structured enough to cover the features of the application.
- Test coverage allows us to find useless test cases. By analyzing test coverage, users can reveal test cases which verify already-tested features and represent duplicate efforts.
- Test coverage makes the code lighter and brings down test run time.
- According to the priority, testers can check out more critical and less critical test cases for the specific application.
- By implementing test coverage, it makes sure to provide good traceability between the generated test cases and given requirements.
- Testers get more ideas about how the selected release is different from the earlier one. Thai make sure to find out the critical requirements more accurately.
- Test management tools always ensure to help in attaining more test coverage.
- By implementing the test, coverage helps to keep track of build cycles and fixes in the project.
- By implementing test coverage also helps to give preferences to the functionality coverage as per the customer’s requirements.
- Test coverage allows impacts analysis to be performed.
- By implementing the test, coverage helps to maximize the multitasking ability of a tester and so helps in determining the EXIT criteria.
Tips for performing test coverage
Here the top tips to perform adequate test coverage are mentioned.
- Make sure to create appropriate test cases which cover the maximum test scenarios, which is required based on the current release.
- Ensure to perform testing before the release so that the focus is provided to cover more scenarios in less time on a scheduled basis.
- Make sure to cover pending items of release when having a new release.
What is Code Coverage?
Firstly let’s clarify a common misconception. People use test coverage and code coverage as if they are interchangeable, but that’s not the actual case.
Code coverage is the percentage of code that is covered by automated tests, and code coverage measures determine which statements in a body of code have been executed through a test run and which words have not. Code coverage systems gather information about the running programs, and then it combines that source information to generate a report on the test suite’s code coverage.
Code coverage is a part of the feedback loop in the development procedure. As tests are developed, code coverage ensures to highlight the aspects of the code that may not be adequately tested and may require additional testing. This loop continues till it meets the same specified target.
Why Measure Code Coverage?
Now, it is well known that unit testing improves the quality and predictability of software releases. Coverage measurements help to avoid test entry. There is a tendency for unit tests to atrophy as the code goes through multiple release cycles. If new code is added to tests, it may not meet the same testing standards which you put in place when the project was released first. By measuring principle, coverage let to keep the testing up to the standards which are required. Testers can be confident that when you go into production, there will be minimal problems as you know the code not only passes its tests but it is also well tested.
We make sure to measure code coverage to know how well our tests test our code and to know whether we have enough testing in place or not. Code coverage is estimated to maintain the test quality over the lifecycle of a project. Code coverage is not a panacea as coverage follows an 80-20 rule. By increasing the value of content becomes difficult with the new test by delivering less and less incrementally. Some code can be challenging to reach with the practical levels of testing if you follow conditions which are often checked at many levels in the software.
Generally, coverage measurement is not a replacement for a good review and acceptable programming practices. You should opt a sensible coverage target and aim for coverage across all of the modules which help to make up the code. By relying on a single overall coverage figure hide large gaps in the coverage.
Test Coverage vs Code Coverage
Test coverage is a measure of how well the tests exercise the different areas in the applications, and we can say that it is a qualitative measure of an existing set of tests. Also, remember that it is a black box technique, and it does not concern itself too much with the code and internal implementation details.
Code coverage is a metric which is often associated with the unit testing, and it make sure to treasure the portion of codebase exercised by test cases. With the code coverage, testers test the functionality of the code and the implementation details as well.
Types of Code Coverage:
Line coverage is one of the most specific types of code coverage, and it checks whether tests cover a given line. Line coverage is represented by the percentage of the lines which are covered by the tests. There are some more types of code coverage available which includes function coverage, block coverage and statement coverage.
The Limitations of Code Coverage:
The main issue of using code coverage as a metric is that it does not tell anything about the quality of the tests and high code coverage is not necessarily great while low code coverage is likely a problem.
The other limitation of code coverage is that it works with code-based tests and particularly unit tests. This type of testing is undoubtedly critical and provides valuable feedback as it is certainly not enough.
Clients will not care that the underlying API works perfectly if they have to see and interact with a faulty UI and so UI testing is very crucial, but code coverage doesn’t help in this.
Code coverage is a valuable metric only if it is used widely and remains alert to its shortcomings. But when it comes to having a big picture view of how well the application is being tested, then the test coverage is what got your back.
How To Perform Test Coverage?
Calculating is one of the hard things about test coverage. Techniques vary for the coming test coverage.
Here are the techniques to perform Test Coverage.-
Product coverage contains os approaching test coverage from a product perspective which means not only verifying the aspects of functions but also the non-functional one like performance, accessibility and usability. Test cases are developed to implement a maximum number of coverage product features, and all essential and optional features are tested according to the priorities components must be tested according to its priorities as set by the product team.
The requirement document of every product mentions the risks which are associated with the project and how to mitigate them as well. Risk coverage is addressed in the stage of test coverage, and certain risks cannot be predicted by this stage which includes risk like market conditions. The closest server is chosen for loading the website depending on the location from where the website is accessed.
Risk coverage ensures to help you to assess the risks an application opens itself to. By employing this process consists of writing down the risks inherent to the application and ensuring the tests cases which are covering them.
Tests are described to provide maximum. Coverage of the product requirement is mentioned in requirement documents. This coverage is undoubtedly one of the most well-known and arguably the most important test coverage techniques as it contains listing out the requirements for the application and making sure to have tests covering them.
How Do You Ensure Test Coverage Is Good?
- Make a comprehensive testing strategy, and it should take into account the application’s requirements and the testing methods which you will be employing as well.
- Make a checklist for all the testing activities, and the further process is to create a list of actual tasks which need to be carried out on the basis of testing strategy.
- Make sure to take into account the different types of testing, both manual and automated. It should also include the size and experience level of the team.
- Prioritize the most critical areas of your applications, and when the resources are scarce, then you need to favour a risk-based approach to testing.
- Ensure to favour the areas of the applications which are critical and have a high probability of having problems.
- Create a list of the requirements for the application, and this will be invaluable while performing product and requirement coverage.
How to Improve Test Coverage?
Remove Dead Code-
You can increase the coverage by decreasing the denominator that is a total code, and this can be done by eliminating the Dead code or Zombie code. Mainly dead code is found in program history in which feature code is added, deleted and disabled. By writing additional tests, you can increase your total code coverage ratios.
Make sure to perform functional testing before removing the dead code and if it performs as per the requirements, then unused can be removed. You can use static test coverage analysis tools to identify the unused dead code.
By eliminating the cloned clone can improve test coverage ratios in the same way as by removing dead code. Mainly the long program consists of base code and code blocks which have clones in the programme. So if you find the clones then make sure to remove it as it will help to increase test coverage ratios.
Increase device coverage-
Ensure to introduce new features and functionalities, which requires additional testing efforts. To increase the test coverage ratios, Perfecto Mobile has a built-in methodology which is based on market usage analytics which looks at the devices from several angles.
Some of the test coverage mechanisms
Unit testing validates the behaviours of the system. By missing a single unit test can cause further testing procedures to be more challenging, and the impact of system failures will have higher magnitude and more likely it will help to prevent the program from operating together. Unit testing is performed at a unit level or module level. The unit tests are intended for the benefits of the programmer, and they are not directly useful for anyone else. If the unit test does their work, then the testers and users both downstream are benefitted from seeing fewer bugs.
Bugs are widely different from issues encountered at the integration stage at this level. Unit testing is the implication which things outside the code goes under test and are mocked or stubbed out. Unit tests should not include any types of dependencies on outside systems. Unit testing mainly tests the internal consistency as opposed to prove that it plays accurately with an outside system.
The unit test helps to improve code reusability as the revised unit tests are perfectly tested. When the development team misses out on unit testing, the odds of reusing buggy code and spawning numerous systems fails and that leads to future changes dramatically.
In functional testing mainly functions or features are tested against requirements mentioned in the Functional Requirement Specification documents.
This testing determines whether a product is suitable for release for customer use or not. At this stage, developers have to receive approval from the testers and SMs to push code changes from Staging to Production.
This testing is also called system testing, and it occurs on the system level. Integration tests cover the whole application and also need some efforts to put together. An integration test is widely used for a wide variety of things from full-on system tests against surroundings which are created to represent production to any test which uses a resource which is not mocked. Integration testing is performed once all software modules which are integrated.
Integration tests mainly require resources like database instances and the hardware to be allocated for them. This test performs more convincing functions of demonstrating the system works and represents production.
The main purpose of test coverage varies depending on the level at which tests are performed, and it also depends on the types of the software being tested. Test coverage metrics for mobile devices differ from website testing. With the help of Amplework, AI-powered test automation tool like Testim can assist teams create best test.