Regression Testing

Given a program P, its modified version of P’, and test suite T used to previously test P, find a way to use T to gain sufficient confidence of the correctness of P.

Note

The point of regression testing is to make sure that new changes didn’t break old code

Steps

1. Identify modifications made to P
2. Select $T^{\prime }\subset T$, the set of tests to re-execute on P’
3. Retest P’ with T’, establishing P’’s correctness with respect to T’
4. Create new tests for P’
5. Create a new complete test set for P’ including the tests from step 2 and 4 and old tests that are not selected provided they remain valid (test minimization?)