Originally posted by logaselvan: Explain the importance of Mutuation testing?
<font size="2" face="Verdana, Arial, Helvetica">A couple of things. First, the nature of this question makes it appear that it is either some sort of question from a homework assignment...or an interview question. In either situation, you're probably going to get a lot in the way of pushback and not much in the way of help.
Second. That having been said, a better question would be to identify what you understand about mutation testing, what you don't understand, and why you might think mutation testing might be important...and then ask for feedback on your thoughts.
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Mutation Testing comes into picture when our product is highly stable, in this scenario we deliberately change some coding and we try to catch errors. You can say that by this we cross check testing team's effort or you can say by this way we make testing team to be more vigilant.
I did a bit of research on this one. It is an interesting concept. Deliberatly introduce errors into the application and make sure that the test suite catches it. When you have introduced all possible errors and the test suite has caught them all, then you know the test suite is complete.
However, there are some basic assumptions. The first, as pointed out by snath, is that the application has to be stable.
I see some problems with this type of testing. The number of mutations could literally be in the millions. Just as with standard testing, where do we want to stop?
Also, unless the application is highly stable and bug free (and no software is bug free), how do you know that the test suite killed the mutant and not some other bug that looks just like the mutant?
So this would have to be introduced within the Test Phase to check on the Automation while still testing to meet a deadline? Seems like an interesting concept, but I don't know where we would have the cycles to do this.
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