Regression testing refers to the process of retesting a specific application after changes have been made to the programming code. The test is used to confirm that changing code within the software has not in any way adversely impacted the original functionality. This is to ensure that the product will operate smoothly with the changes that are made to the feature that already existed. The regression testing is a software test used to make sure that introducing change to the product did not introduce new bugs as well.

Regression testing is technically a confirmation method. The test cases are typically mandated to execute over again multiple times, so they are usually automated as running the same case numerous times becomes tedious and takes up a lot of time. Regression testing doesn’t depend on program language with its purpose being to test for modifications or updates that have been performed and verify the effects they are having on the modules existing.

When To Perform Regression Testing

Regression testing dictates that it be performed once verification has been made where there have been changes or a new function, unless a release is due to take a long period of time, e.g. months, to finish, regression testing should be enacted on a daily cycle. If there are to be weekly releases, the regression testing will be done when the functionality testing is complete for changes.

Types of Regression Testing

The most precise regression testing definition is a process of testing the software after the code change to ensure that the application is crash-resistant and functions as expected. It is used in the instance that some parts of an application or a code have had undergone a change. Here are the types of regression testing that are commonly utilized:

• Corrective. This testing takes place when there has been no change brought to the software and the existing test case is appropriate to use in the test.
  
  
• Progressive. Modifications are placed in the specification of a product with new test cases being designed.
  
  
• Selective. This is when a subset of particular experiments are used in order to cut down on costs for retesting as well as the effort. If modifications are made, a test case has to be re-executed.
  
  
• Retesting everything. This type of regression testing takes a lot of time and is usually automated as testers rarely use it. It is not useful when there are only small modifications or changes or even none at all to the app.
  
  
• Complete. This regression testing is particularly useful when there have been numerous changes to the original code and is very valuable in detecting unexpected bugs.

Benefits of Regression Testing

The main reason for conducting regression testing is to confirm any issues that may have developed due to changes made to the system. Conducting this testing has a number of benefits:

• Possibility increases for tracking bugs because of the changes.
• Allows research for unforeseen side effects occurring with the new system.
• Very valuable in conditions where changes are constant with products.

Regression testing is an effective way to expose functioning or non-functioning bugs or errors within tested software after an update or modification or change of some kind has been made to the system. It is a crucial part of maintaining the safe and proper operation of your application.