Migrate stress tests to Google Test?

[egpbos]

Currently, RooFit testing is done from scripts in $ROOTSYS/roofit/roofitcore/test that are included into $ROOTSYS/test/stressRoofit.cxx to actually run. These scripts can be used in two modes: test and write mode. In write mode, the test code is run and the results are stored in the reference file, $ROOTSYS/test/stressRooFit.root. In test mode, the same code is run and the results are compared to the results in the reference file. This also works for things like plots, which can also be stored in .root files. This makes the tests easy to manage; for instance when the adaptive curve interpolation algorithm of function projections in RooPlot would be modified, it would be easy to regenerate the reference result. Another tool in the stress suite for when tests fail is the option to output the reference and test results to a new file that can be opened in ROOT for interactive inspection of what went wrong.

To increase user/beginner friendliness, generalizability and possibilities for code/skill reuse, it would be nice if the stress tests could be ported to the Google Test framework that is now integrated in ROOT. The main constraint is that all the above functionality has to be preserved for debugging purposes, so it has to be investigated if this is possible from gtest.