Topic :: Mutation Testing

Reply / yogesh

In mutation testing we are making some changes in code and
again run the test cases in order to find whether that test
cases are capable of finding bugs.

Reply / ramprasad.s

Mutation Test is to Make changes over the Passed Test Case & See
That the Build should show defect.

Reply / srikar.k

forcibly injecting bug and testing the functionality

Reply / pune tester

With mutation testing, the system/program under test is
changed to create a faulty version called a mutant. You
then run the mutant program through a suite of test cases,
which should produce new test case failures. If no new
failures appear, the test suite most likely does not
exercise the code path containing the mutated code, which
means the program isn't fully tested. You can then create
new test cases that do exercise the mutant code.

Reply / prasanna

This is one of the White Box Testing Technique . Generally
programmer are following this technique to test the change
in the program to estimate the correctness & completeness
of the program.

for example
1. if all tests passed in the program that is good program.

2. If all tests passed but in the program some change is
there .don't say passed. this is not a good testing

3. in all tests passed except change test failed. this is
the complete testing.

Reply / swetcha

mutations are introduced into a program to test the adequacy
of the test data. A mutation is a SMALL CHANGE made to the
program. The effects of that data should be made up in some
tests. If it doesn't ,the test set is probably inadequate.
and this type of testing is called mutation testing...also called as debugging

The person who is changing the code by adding mutations
should see how the code works.

Reply / anand kumar

Mutation means a change.

While u r doing unit testing u'l prepare some unit
test cases and test the program. After that to estimate the
testing u have conducted u'll introduce some mutations
(changes) in ur program/unit and repeat the same tests then
few test should give wrong results as u use the same data
and test procedure then it shows the completeness of ur
test cases for ur unit test. if ur test passes even after
making these mutations means u r not test all flows of ur
program which implies that ur test case r not completely
tests the unit.

Reply / shankar

Mutation testing is performed as part of Unit Testing. In
this testing phase, programmers will perform some change in
the coding and execute previously completed tests. If all
the tests are passed, then he will concentrates on the
same. If any one of the test is failed then he will
concentrate on the further coding.

Reply / suneel reddy

it is nothing but estimating the efficiency of test data by
deliberately introducing bugs

Reply / ashok reddy

Mutation means absolutely bug injection

Reply / poonam

it means that purposely u introduce bugs & it is also known
as debugging.

Reply / tushar

A testing methodology in which two or more program mutations
are executed using the same test cases to evaluate the
ability of the test cases to detect differences in the


A method whereby errors are purposely inserted into a
program under test to verify that the test can detect the
error. Also known as error seeding.


A method to determine test set thoroughness by measuring the
extent to which a test set can discriminate the program from
slight variants of the program. Non-intrusive Testing:
Testing that is transparent to the software under test; ie,
testing that does not change the timing or processing
characteristics of the software under test from its behavior
in a real environment. ...

Reply / jeekarthik

After the initial testing is complete, mutation testing is
taken up. The idea behind mutation testing is to make a few
arbitrary small changes to a program at a time, each
time the program is changed it is called a mutated program;
the change is called a mutant.

A mutated program tested against the full test suite of the
program. If there at least one test case in the test suite
for which a mutant gives an incorrect result, then the
mutant is said to be dead.

If a mutant remains alive even after all test cases have
been exhausted, the test suite is enhanced to kill the

The process of generation and killing of mutants can be
automated by predefining a set of primitive changes that
can be applied to the program.

The primitive changes can be:
? Altering an arithmetic operator,
? Changing the value of a constant,
? Changing a data type, etc.

A major disadvantage of mutation testing:
? computationally very expensive,
? A large number of possible mutants can be generated.

Reply / venkat

Make perfection in coding the developers intentionally made
mistakes for particular object to check whether it will
work same as correct code

Reply / rajesh.veggalam

Mutation test means a change in your program programmers
are perform changes in tested programs to estimate
completeness and correctness of the program testing