Issue with ROOT.RDF.Experimental.FromSpec when TTree is inside a sub-directory

[Pedro_Silva]

Dear all,
while trying to use a json file to specify a RDataFrame I have stumbled into an issue.
If the TTree to be read is inside a sub-directory any attempt to use RSampleInfo seems to fail with the following error

 logic_error: RSampleInfo: sample data was requested but no samples are available.

This hinders a bit the usage of this fine feature in RDataFrame.
I have made an example to reproduce the issue here [1] using e.g. [2]
Would it be possible to have workaround for the cases where a sub-directory has been used?

Thanks,
Pedro

[1] /afs/cern.ch/user/p/psilva/public/rdf_byspecs
[2] tested on lxplus9 with /cvmfs/sft.cern.ch/lcg/views/LCG_105/x86_64-el9-gcc13-opt/setup.sh

[vpadulan]

Dear @Pedro_Silva ,

Thanks for reaching out to the forum! Indeed I can reproduce the problem and I have opened a PR with the fix at [df] Correctly update sample info when dataset is in TFile subdirectory by vepadulano · Pull Request #15907 · root-project/root · GitHub.

Cheers,
Vincenzo

[Pedro_Silva]

Dear Vincenzo,
many thanks for the fast reply and update! Very much appreciated,
Best,
Pedro