Coverage matrix (lines X test cases hit that line OR test case X lines hit )

[namanr...@gmail.com]

Hello everyone,

I am eager to know if Jacoco or EclEmma is able to provide coverage matrix? Coverage matrix is matrix of test cases X lines covered, where each row will be a vector of 1s and 0s. ! represents, corresponding line is covered in that test case, represented by row. and 0 will represent its counterpart. This matrix is useful in many fault-localization methods. I go through documentation but didn't find anything fruitful.

I would love to know if this is possible in jacoco or eclemma.

[Marc Hoffmann]

Hi,

JaCoCo/EclEmma has no idea about the nature of Java application which is
running on the JVM. In particular has no notion of a "test case".
Therefore this feature is not directly supported in JaCoCo or EclEmma.

But it is possible to build it on JaCoCo APIs. For example SonarQube has
an implementation for this in their reports:

https://deors.wordpress.com/2014/07/04/individual-test-coverage-sonarqube-jacoco/

Regards,
-marc