Retesting Vs Regression Testing

Retesting Vs Regression Testing

What is Retesting?

Test engineers often find bugs while testing software applications. It is, after all, their undertaking to do so. After assigning these bugs back to the developers, they need to check if the bug is fixed. This is called retesting.
Retesting is when a test is performed again on a specific feature that was not functional during the previous test to check for its functionality. Retesting is typically performed by the same testers who identified the defect in the first place.

An instance that may warrant a retest:

  • Let’s take an example of an eCommerce website selling phones. While conducting tests regarding the functionality of the elements, it was found that the like button for the products wasn’t working.
  • Upon flagging this error, the test engineer will task the developer to fix the defects.
  • Once the developer reverts, the test engineer would need to retest and check if this specific feature has been fixed and is working as it should.

When to use Retesting?

  1. Retesting can be used to test a specific component to validate its functionality.
  2. It can also assert or verify to the developer that a module or component is non-functional.
  3. Retesting can be done for various reasons. However, the common purpose of any retest is to repeat a test and confirm the existence or non-existence of a particular defect.

What is Regression Testing?

When a developer introduces updates or changes to the software, ensuring that a butterfly effect hasn’t occurred is essential. A small change in the application could lead to unintended defects elsewhere; Automated Regression Testing takes a generic blanket approach to look for these unintended defects.

  • Defining regression testing is meant to reaffirm that no unintended regressions or defects have occurred due to an update or code change in the application.
  • The keyword being reaffirmed, while retesting aims to check whether a specific bug has been fixed, regression testing tries to do a catch-all test to affirm that no unintended bugs have occurred in the application.

When to use Regression Testing?

  1. There is an update or enhancement carried out on the application.
  2. A defect found in the application is fixed.

Key difference: Retesting vs Regression Testing


Regression Testing

Retesting has tests explicitly designed to check whether known bugs have been fixed.Regression testing isn’t targeted testing for known defects.
Retesting does not focus on the previous version’s functionality. Instead, it aims to check whether functionality has been restored following a bug fix.Regression testing is change-oriented and mainly aims to check whether the previous versions’ functionality is maintained following a change/update to the application.
Since retesting checks for a specific defect, it can’t be automated.Automation is prevalent for regression testing. Manual testing every time a change or update is made to an application would be very irrational. Automation is far more complementary to carrying out blanket tests for unintended bugs.
Retesting doesn’t have to be a part of the testing process unless a bug is found and corrected; Therefore, retesting is not a guaranteed part of the testing process.Regression testing is the norm and is always a part of the testing process. Every time the application’s code is altered, it is good practice to perform regression testing.
A higher priority is applied to retesting since this testing focuses on fixing known defects.Regression testing has a lower priority than Retesting since it simply conducts a sweep of the application to check for potential unanticipated defects.
Since only a certain defect is explored in retesting it is far less time-consuming.Regression testing often explores large parts of the application to uncover bugs and can be more time-consuming than retesting.

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