Software testing methods are essential in building software. It helps developers deal with different types of bugs. As we all know, these bugs may range from a missing semicolon to a critical business requirement. Thus, software testing becomes an essential part of a test driven development environment.
We are in the era of process automation. Today, businesses are dependent on one or more software products. Therefore, software quality becomes crucial. As a result, the demand for robust software increases.
In this guide, let’s learn the role of software testing, the different software testing methods, testing metrics, and how APM solutions like Retrace and these methods help you stay ahead in software testing and quality assurance.
What is Software Testing
Before delving into the different testing methods, let’s define software testing first.
Software testing is a process to determine the quality of a software product or service. These are performed by software testers to find errors and bugs. Testers formulate a batch of use cases and conduct test runs.
After every batch of a test run, features with defects are sent to the developers to fix. Then, developers send the fixed features back to the testing team for re-evaluation. After this, the software tester runs the test cases to confirm that there are no errors. The cycle continues until the software product attains a desired level of quality.
In software development, there are a variety of testing methods. Choosing the right tools to use can prove to be cumbersome. Thus, it is the job of the Quality Assurance team to establish a suitable testing method to use and assess the methods if it fits with the product type and the development team’s attributes.
Testing is vital as it measures all aspects of the software’s functionality. Remember, a crucial defect left undetected can cause vast amounts of losses to a business.
8 Software Testing Methods
To understand the concept of these methods, let’s have an overview of software testing. Software testing belongs to two broad categories: static and dynamic analysis. Let’s explore further.
The static analysis doesn’t involve the actual execution of the code. Instead, it examines all possible behaviors that might arise during run time. The best example is compiler optimization.
Software testers perform static analysis through an examination of documents. These documents include specification requirements, models, design architecture, and legacy codes (when upgrading an application).
The traditional static analysis includes:
- code review
- code inspection
- algorithm analysis
- proof of correctness
Dynamic analysis involves actual program execution to expose possible errors and failed functionalities. Also, part of dynamic analysis is behavioral and performance properties of the software.
The software tester’s goal is to identify as many faults as possible. Static analysis is best for identifying errors at the early stage of software development. On the other hand, dynamic analysis performs well in parallel with development. Hence, these two are complementary and offer better effectiveness if used together.
Additionally, testing methods may also fall in another type of categories:
This method determines whether the product of a given development phase satisfies the requirements. These requirements are either established at the start of the development or the beginning of a certain phase. Testers verify the features stated in the requirement specification, design specification, code, etc. are correct.
Validation confirms that a product serves its purpose. It involves activities that check whether a product achieves its customer’s expectations. Also, it focuses on the final product, which undergoes extensive testing from the customer’s point of view. To sum it up, validation establishes whether the product meets the overall expectations of the users.
Let’s delve into the most commonly used software testing methods today.
One of the most common software testing methods is black box testing. As the name suggests, it is like treating the software product as a black box. Testers perform testing without knowing the overall content of the software. The testing process is a simple input-process-output paradigm. Tester knows what are the necessary inputs and expected outputs, but not the process.
The black box testing method tests the functionality of an application based on the requirement specification. It does not focus on the internal structure or code of the application.
Black box techniques include:
- Boundary Value analysis
- Equivalence Partitioning
- Decision Tables
- Domain Tests
- State Models
The basic concept behind white box testing is that testers have prior knowledge of how the software works. Its main goal is to know how the software should work. Then, perform testing to verify that it works properly.
The white box testing technique is used in development to examine the program structure and business logic. Testers perform validation of the entire code structure of an application. It is also called clear box testing, glass box testing, open box testing, transparent box testing, and structural testing.
White Box Testing Techniques include:
- Statement Coverage – It examines all the programming statements.
- Branch Coverage – Performs a series of test runs to ensure detailed testing of all the branches.
- Path Coverage – Perform testing on all the possible paths to cover each statement and branch.
The next question would be, why do we perform White Box Testing? The answers are simple.
- To check correct execution of all the independent paths within a module.
- To verify all logical decisions on their true and false values.
- To determine that all loops are within their boundaries and the operational bounds of internal data structures are valid.
Also, to discover the following types of errors:
- Logical error concerning functions, conditions, or controls related to design and implementation.
- The design errors due to the difference between the logical flow of the program and the actual environment.
- Typographical and error syntax.
In scripted testing, a tester follows an outline, which is also known as script. This script is essential in the testing method as it includes test cases and its corresponding test steps. Indeed, these steps are scripted and are suitable for fulfilling a specified requirement. Scripted box testing works well with functional and non-functional testing.
The opposite of scripted is exploratory testing. This is where testers have full autonomy to work around the software application based on their instinct. This method is perfect for finding hidden risks or errors.
Remember that no matter how stringent scripted testing is, there are still possibilities for some glitches to occur. For example, an incorrect tooltip content might confuse end-users or a redundant button that may confuse the users.
Truly, exploratory testing understands how actual users navigate the application. On the other hand, scripted testing ensures that the software is ready for deployment. Hence, software testers and product owners always use these two methods in parallel.
In manual software testing, human judgment and intuition always benefit the project. Testers use manual testing with the scripted or exploratory method. The benefit of manual testing is getting fast and accurate feedback. Also, it is less expensive as it doesn’t involve automation tools and processes.
Human judgment may be an advantage as it can also make this method less reliable. For example, when there is a limited number of testers for a large-scale project, it can cause bottlenecks. These bottlenecks will wear out testers and often result in several undetected bugs.
Automated testing uses scripts and tools. It makes this method more reliable as the test runs automatically. As a result, it finds more bugs compared to a human tester. Also, testers are allowed to record the automation process, allowing them to reuse and execute the same kind of testing operations.
Some software testing tools like Selenium can increase productivity and provide fast and accurate testing results. Additionally, it has a wider coverage because automation testing never skips even the smallest unit.
However, the tools used to run automation testing are expensive, which may increase the cost of the testing project. It is a risk to take as there are tools that are not yet foolproof. Moreover, every automation tool has its limitations, which reduces the scope of automation.
One of its known limitations is test script maintenance. The development team and business owners should understand that maintaining scripts and testing different but costly processes.
Therefore, most testers attest that automation and manual testing work hand in hand. These methods provide fast bug identification while delving into UI’s visual aspects (e.g., colors, font, sizes, contrast, button sizes, etc.).
To maximize automated testing, here are six tips to increase development speed while reducing costs.
It is just practical to use waterfall testing if you’re using the waterfall software model. This testing happens after the development phase is complete. It is ideal for projects with defined requirements and is unlikely to change.
The few advantages of waterfall testing include a well-structured and well-documented testing process. In a waterfall model environment, testers and developers don’t need to communicate as they work independently. Additionally, all the features of the project are developed and delivered together. It makes the testing process manageable as every stage has its deliverables and a strict review method.
For its disadvantages, it requires excessive documentation with a rigid structure. It is not ideal for large-scale projects as testing happens only at the end of the project. This is only suitable if bugs are easier solved, which is rarely the case in software development.
Agile is one of the well known software testing methodologies today. It matches the postulates of agile software development. Just like the development, agile tests work in sprints and test plans. Software development and testing are simultaneous. It evolves as the software itself progresses.
As software development itself is becoming test-driven, more and more teams are adopting Agile processes. Agile continues to be on the rise, encouraging testing teams to test earlier in the development process.
What is Software Testing Metrics
Software testing metrics are like scorecards. It quantitatively measures the progress and quality of the software testing process. Its goal is to improve the efficiency and effectiveness of the software testing process. More importantly, it helps make better decisions for further testing processes by providing reliable data.
To understand metrics, let’s consider calculating test cases. For example, if a Project Owner (PO) wants to know the status of the test cases in percentage, here is a formula:
Percentage of test cases executed = (No. of test cases executed / Total no. of test cases written) X 100
Also, use this formula to calculate other parameters like passed and failed test cases and others.
What Software Testing Strategy is Right For Your Business?
The software testing field is always evolving. Be it domain, process, or technology. Thus, choosing a proper Testing Methodology is not an easy task. Also, there are several factors to consider in implementing such methods. These include business requirements and the timeline of the software product.
However, one can choose an easier way. Application Performance Management (APM) is an option to expedite the testing process. Prefix from Stackify helps developers understand every code and find bugs lurking around functions, methods, dependencies, etc. On the other hand, Retrace proactively identifies issues related to Quality Assurance and offers continuous improvement in the production environment.
You can opt to use single or multiple software development and testing methodologies. However, you will need sophisticated tools to provide flexible and efficient end products that satisfy the customer’s needs.