Mutation Testing

Mutation testing is used to design new software tests and evaluate the quality of existing software tests.
Contributed by

Sebastien Wains

Published July 25, 2022

What Is Mutation Testing?

Mutation testing involves modifying a program in small ways.

Each mutated version is called a mutant and tests detect and reject mutants by causing the behavior of the original version to differ from the mutant. This is called killing the mutant.

Why Do Mutation Testing?

The goals of mutation testing are multiple:

  • identify weakly tested pieces of code (those for which mutants are not killed)
  • identify weak tests (those that never kill mutants)
  • compute the mutation score, the mutation score is the number of mutants killed / total number of mutants.
  • learn about error propagation and state infection in the program

How to do Mutation Testing?


C#, Scala, Javascript

Look at Mutation Testing

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