test coverage: mkdir -p over a directory which already exists #1022
Description
PR #1019 made me realize we're not testing the case where mkdir -p is used on a path which already exists. I think there are 2 interesting subcases here:
# Try making a folder which already exists
$ mkdir -p path/to/<folder which exists>
# Try making a folder which doesn't exist, but is a subdirectory of some folders which do exist
$ mkdir -p path/to/<folder which exists>/<some new folder which doesn't exist>