develop a job that runs descartes on a change

[bbaudry]

Create a task that

• [ ] detects the nature of the change: change in the test suite or in the app code or in both.
• [ ] identifies the part of the code that should be mutated
• [ ] identifies the set of test cases that need to be executed

[nicolabertazzo]

My proposal to this task (for jenkins pipeline projects ) is:

1. In Jenkins, from the current build, get the list of [change set](http://hudson-ci.org/javadoc/hudson/model/AbstractBuild.html#getChangeSet()) (the files changed from the previous build)
2. from the change set get the list of the test file changed (the files stored in a specified folder)
3. Execute the mutaion only to the test classes that are changed

We can develop and distribute this feature as a Jenkins Shared libraries that for each build return the list of test changed in the change set. This list can be used as targetClasses pit parameter.

To develop this feature we can use these Jenkins functionalities:

• currentBuild variable
• [getChangeSet method of currentBuild variable](http://hudson-ci.org/javadoc/hudson/model/AbstractBuild.html#getChangeSet())
• junit plugin and TestResult class

[bbaudry]

in step 2. I suggest to consider 3 different situations

• change in test classes
• change in app code classes
• change in both

[bbaudry]

Do you think that this task can be developed independently of Jenkins? This way we could reuse it in a scenario based on pull-requests