The regression test definition is clear. It’s a test to ensure that a previously tested software still performs flawlessly after a change. However, planning these tests is not so simple, especially when time and resources are limited. When these aspects are limited, the test planning tends to shorten, time is wasted on adjustments, and tests are performed under pressure, resulting in human failure when the proper cases are not selected.
How can an efficient regression plan be achieved?
We need a suite strong enough that it can be run during a defined period and includes the tests cases most likely to find a failure. Here are some recommendations for improving your regression testing planning:
From the beginning of the test case estimation, you should assign execution priorities: High, Average, Low and key words like Regression, Sanitation, and so on for the test cases. This way, filtering can be done faster through priorities and tags, making it quicker to differentiate which cases are more important.
Use of design techniques for case tests
For example, you can use entities such as International Software.
Improve test coverage, with fewer test cases
The Testing Qualifications Board American Society for Quality mentions various techniques for the creation of test cases that result in an improvement in coverage. Once applied, these techniques mean fewer test cases are obtained and there is a greater coverage factor than with an empirical creation base. By having a lower number of test cases, we can reduce the number of exhaustive tests and execution times.
Adequate classification by suites
Dividing the test cases according to a module system allows you to select the right cases when constructing your regression testing plan. You should avoid ambiguous names or those different from what was defined in the requirements in your folders and suites, and for the names showing in the system.
If your case managing tool allows, it’s ideal to organize the suites with hierarchies according to the same application, so that the selection of test cases per component can be natural. For example, if the module “Transfers” has options such as “Local transfers”, “Transfers to third parties”, and “International transfers”, then these should be located in a parent folder labeled “Transfers” with three child folders.
This is useful for keeping your test cases organized, which speeds up the search for test cases. Keep in mind that the hierarchy shouldn’t become so extravagant. When you get to having 4 or 5 sublayers, it becomes more inefficient than helpful.
As our application grows, changes, or improves, it becomes more and more necessary to dedicate time to reviewing if these changes affect our current test cases. You need to review if previously created test cases become invalid or need to be updated.
If we find that a change will affect the test cases, then we should include updating tasks. Under the old system model, with cases that have never been updated, we recommend including a periodic review of all existing test cases.
Definition of the type of regression to execute
Not all regression tests require an execution of 100% of the test cases (Full Regression). In many cases, the changes affect specific components, which means your regression testing can focus on those specific modules. You can verify the rest of the system with smoke testing.
In these cases, a dependency analysis is necessary to have certainty that the changes were applied don’t affect other parts not contemplated in the regression of the component.
Regression testing can turn into a very long process. Incorporating automated testing has some advantages. First, the execution capacity increases while the testing time decreases. Automated scripts can be tested over and over again without wearing down the team. Additionally, you can incorporate different environments into the test without increasing the time needed to execute them, since they can be executed at the same time.
Generally, the best way to create an effective regression testing plan is to plan it from the very first stages of the test cases. If you are preparing for a partial regression, and haven’t followed any of the recommendations, then the best thing to do is trust in your team to choose the indicated test cases, keeping in mind that this takes time.
Searching for complementary strategies to improve coverage, such as bug verification and exploratory tests can boost the confidence we have in the testing. There are always ways to improve effectiveness and efficiency of testing, but keeping with the old system ends up taking a lot of time and using a lot of budget.