Running datalad containers-add fMRIprep -i '/data/project/singularity/fmriprep-20.2.0.simg' -d '/data/project/hcp_movies/hcp-openaccess/' did not result in an error even though data/project/singularity/fmriprep-20.2.0.simg does not exist in the dataset.
Running
datalad containers-add fMRIprep -i '/data/project/singularity/fmriprep-20.2.0.simg' -d '/data/project/hcp_movies/hcp-openaccess/'
did not result in an error even though data/project/singularity/fmriprep-20.2.0.simg does not exist in the dataset.