Arvados

arvados.commands._util.validate_filters raises a ValueError that gives more detail about exactly what's wrong with the filters. Figuring out a way to include that information would be better than this:

$ arv-mount --filters /dev/null $XDG_RUNTIME_DIR/keep
usage: arv-mount [-h] [--retries RETRIES] [--version] [--allow-other] [--subtype STRING]
                 [--all | --custom | --home | --shared | --by-tag | --by-id | --by-pdh | --project UUID | --collection UUID_or_PDH]
                 [--mount-by-pdh PATH] [--mount-by-id PATH] [--mount-by-tag PATH] [--mount-home PATH] [--mount-shared PATH]
                 [--mount-tmp PATH] [--debug] [--logfile LOGFILE] [--foreground] [--encoding ENCODING] [--file-cache FILE_CACHE]
                 [--directory-cache DIRECTORY_CACHE] [--ram-cache | --disk-cache] [--disk-cache-dir DISK_CACHE_DIR]
                 [--disable-event-listening] [--read-only] [--read-write] [--storage-classes CLASSES]
                 [--crunchstat-interval CRUNCHSTAT_INTERVAL] [--unmount | --unmount-all | --replace]
                 [--unmount-timeout UNMOUNT_TIMEOUT] [--filters FILTERS] [--exec ...]
                 mountpoint
arv-mount: error: argument --filters: invalid <arvados.commands._util.JSONArgument object at 0x7fd229d601c0> value: '/dev/null'