The growing emphasize on software quality has led organizations to make huge investments in the QA process. The new trend of codeless test automation has offered a greater advantage of increased productivity, consistency, and accuracy. There are two major codeless testing approaches that are popularly adapted by organizations depending on their requirement - waterfall and agile testing models. The choice of testing methodology depends on the software development approach being followed, whether it is waterfall model for development or agile methodology.
Both the methods, waterfall and agile, are unique in their own way and offer greater results under specific conditions. It is important to understand the scope of the project, required outcome, project size, budget, and time duration. Once the goal is set and the requirements are clear, the right testing method can be chosen.
Waterfall testing methodologies are the approach that corresponds to waterfall software development model. The waterfall developmental model is a linear-sequential cycle that includes the processes in a specific order - requirement analysis, design, execution, testing, deployment, and maintenance. Here, testing is carried out only after the execution is completed, hence, there is no scope for identifying the errors in the earlier stages.
Waterfall model testing is phase-oriented testing, where the tester will have to wait until the software is developed and sent for quality check. Here, the tester receives the end-product and tests if it works as expected. The list of changes, errors, or discrepancies are than sent to the developer for rectifying. It is a to-and-fro process, that involves the software coming to the developer until all the errors/bugs are dissolved. This method of testing is suitable for smaller projects, however, for larger-scale development, this method may be expensive. Every time a change/error is sent to the developer, the requirement changes and various modifications must be done to fix it, while ensuring that this change is not affecting the other parts of the software. Such scenario may involve huge cost, time, and effort.
Advantages of waterfall testing
- It is most suitable for smaller projects
- Project management is easy; as the workflow progresses one stage at a time, it gets easy to manage the over project
- Since, requirements cannot be changed once the project begins, the project should be well planned and executed
- Process and results are well documented for further analysis
- Each stage is independent of the other, hence, there is lesser confusion and conflicts between the teams
Limitations for waterfall models
- It is proven to be tedious for larger projects
- The rigid nature of the process doesn’t allow to make any changes in the previous stages
- Since, testing is done after the complete development is over, fixing a bug/error can be a costly affair
Agile testing is a multidisciplinary approach that involves developers, testers, and other subject matter experts. Agile testing is a part of the development cycle, it is performed simultaneously along with the development. It supports the continuous integration and deployment cycle, and allows a streamlined communication channel between developers, testers, project manager, and the client.
In agile models, testing is not a different phase and it takes place alongside the Software Development Life Cycle (SDLC). It is performed by planning and executing requirements, design, coding, and generation of test cases. The testers will identify the error/bug in the earlier stages and the developers will fix them immediately even before moving to the next stage. Hence, when the software development is complete the product is ready for deployment without any glitches. Such an approach can reduce cost, time, and effort considerably.
Advantages of agile testing
- It can be efficiently implemented for larger projects
- Since the developers, testers, and the client are involved in each stage, there is no scope of deviation from the expected results
- Promises higher quality
- It is based on an incremental approach, so one can be assured of reduced testing and developmental risks
Limitations of agile testing
- Not suitable for smaller projects as it is expensive
- Since large projects consider this approach, proper planning and execution is required
- If the goal of the project is not well-defined before its commencement, this may not give you the expected results
Difference between waterfall and agile testing
Which one to choose?
Waterfall and agile models have their set of advantages and disadvantages, it is the decision of the organization to choose the one the best suits their requirement. However, waterfall models have also been proven successful in today’s development trends, agile method would be a better choice for its flexibility, ease, and result-oriented approach.
Both the methods may show expected results in the Dev environment, but in real-life scenario, it might not be always the same. The fluctuating infrastructural and operational requirements may lead to discrepancies in the results. Under such a scenario, the waterfall method may not be effective as the testing is done after the development is completed. Choosing agile approach will have development and testing go hand-in-hand. Hence, error/bugs can be identified earlier in the development stage, run the process quickly and seamlessly, while ensuring all customer requirements are met. Agile approach is the most suitable for today’s technological-driven, fast-paced world.