Descartes Tutorial at ASE 2018


Place: Montpellier Corum Conference Center
Conference: ASE 2018
Instructors: Benoît Baudry (KTH), Vincent Massol (XWiki), Oscar Luis Vera Pérez (INRIA)

Let the CI spot the holes in tested code with Descartes tool

Descartes

Bring your laptop, your favorite Java project (with JUnit tests) and find out how much of the covered code is actually specified by the test suite!

In this tutorial, we introduce the intriguing concept of pseudo-tested method, i.e. methods that are covered by the test suite, yet no test case fails when the method body is removed. We show that such methods can be found in mature, well-tested projects and we discuss some possible root causes. Attendants have the opportunity to experiment hands-on with our tool, called Descartes tool, which automatically detects pseudo-tested methods in Java projects.

The tutorial is structured in three parts:

  1. Introduce the concept of pseudo-tested methods. We position these methods in the context of test adequacy assessment and contrast them with code coverage and mutation testing. We illustrate the concept with examples found in large, well tested open source projects developed by the Apache foundation, Google, Amazon and Spotify.
  2. Let the attendants discover the presence of pseudo-tested methods in their own Java projects using our Descartes tool. This tool automatically transforms all the methods that are covered by one test case at least into empty methods. Then the test suite is run on each transformed method, leveraging the mature and efficient transformation and test execution engine of PITest. Attendants will learn how to configure the tool for their projects and interpret the results.
  3. We demonstrate the usage of Descartes tool in a Continuous Integration (CI) environment. We show how it can be integrated within Jenkins and Maven to monitor the evolution of a test suite. This last part is also a mix of presentation and hands-on with specific examples taken from XWiki, a well-tested, active Java-based CMS. 

Find more details about this Descartes tutorial on the ASE 2018 Conference website