Why is Regression Testing Necessary?
Regression testing is necessary because many times modifications in one part of the code cause unexpected problems in a “totally unrelated” area of the code. Example scenario: A video driver was released for the Diamond Stealth video board. Complaints started to come in that HP InkJet drivers were crashing when doing a print preview. It was discovered that the print preview functionality calls the video board’s font rasterizing functions to generate the print preview. A bug in the video boards font rasterizing function was causing a memory fault when called by the HP print driver. This caused the error to appear like it was in the printer driver and not the video driver. Summary Testing allows developers to deliver software that meets expectations, prevents unexpected results, and improves the long term maintenance of the application. Depending upon the purpose of testing and the software requirements, the appropriate methodologies are applied. Where possible, testing can be automated
