LuMutator

A tool that expands tests to kill survived mutants

Mutator: MathMutator (Replaced integer subtraction with addition)
src/main/java/bank/Bank.java:
  96                Customer toCustomer = customers.get(toCustomerId);
  97
  98                if (fromCustomer.getBalance() >= amount) {
! 99                    fromCustomer.setBalance(fromCustomer.getBalance() - amount);
  100                    toCustomer.setBalance(toCustomer.getBalance() + amount);
  101                    return true;
  102                }


src/test/java/bank/BankTest.java:
  58
  59        boolean success = bank.internalTransfer(customer1.getAccountNumber(), customer2.getAccountNumber(), balanceCustomer1);
  60
+ 61        assertEquals(0, customer1.getBalance());
  62        assertEquals(balanceCustomer1 + balanceCustomer2, customer2.getBalance());
  63    }
  64

(4/5) Add this new assertion? (Y/N):

Download

Either visit the releases page to directly download the jar files or visit packages page to add the jar files to your pom.xml.

How to use

Using PITest

1. First let PITest run the mutation analysis and generate the reports, make sure there's a directory /target/pit-reports present afterwards.

mvn test -Dfeatures=+EXPORT org.pitest:pitest-maven:mutationCoverage

To include PITest into your project, add the following plugin in your pom.xml:

<plugin>
    <groupId>org.pitest</groupId>
    <artifactId>pitest-maven</artifactId>
    <version>1.4.7</version>
    <configuration>
        <outputFormats>XML</outputFormats>
    </configuration>
    <executions>
        <execution>
            <id>pitest</id>
            <goals>
                <goal>mutationCoverage</goal>
            </goals>
        </execution>
    </executions>
</plugin>

2. Set up the config file for LuMutator; a default one can be downloaded on the releases page.

3. Now everything is ready to call LuMutator:

java -jar pitest-example-1.0.jar -c config.xml

Using another mutation tool

Use the lumutator-core-1.0.jar library to call LuMutator and pass the survived mutants. An example of how this is done can be found in the pitest-example module.

Publication

• Z. X. Lu, S. Vercammen and S. Demeyer, "Semi-automatic Test Case Expansion for Mutation Testing," 2020 IEEE Workshop on Validation, Analysis and Evolution of Software Tests (VST), London, ON, Canada, 2020, pp. 1-7.