Regression is a type of testing that gets performed to ensure that a change made to the system has not broken the existing functionality of the system. It is done after an enhancement or defect fixes are made to the system. Impact analysis is required to identify possible impacted areas due to those changes.
Selecting test cases for regression testing require:
- Knowledge on the bug fixes and how it affects the system
- Includes core/critical features of the product
- Include the test cases in error-prone areas
- Include areas that the changes have impacted
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