[Bug 13901] New: Empty quotes adds cwd to SRC directories

[Joe]

I brought this up on the list years ago and was told it's a feature, not
a bug.

Even if some other GNU or Linux commands have this "feature", it still
violates the principle of least surprise.

It's also pretty hard to discover because a null argument is literally
invisible.

Joe

On 4/17/19 9:54 AM, just subscribed for rsync-qa from bugzilla via rsync
wrote:
> https://bugzilla.samba.org/show_bug.cgi?id=13901
>
>             Bug ID: 13901
>            Summary: Empty quotes adds cwd to SRC directories
>            Product: rsync
>            Version: 3.1.3
>           Hardware: x64
>                 OS: Linux
>             Status: NEW
>           Severity: normal
>           Priority: P5
>          Component: core
>           Assignee: wayne at opencoder.net
>           Reporter: daniel at grundstrom.email
>         QA Contact: rsync-qa at samba.org
>
> Created attachment 15076
>   --> https://bugzilla.samba.org/attachment.cgi?id=15076&action=edit
> For cmd 'rsync "$UNSET_VAR" --debug=ALL5 --verbose --recursive -- /data/src/
> /data/dest/'
>
> Hi! It's my first bug report here so let me know if I should clarify anything!
>
> If you add empty quotes to the rsync command line, it is interpreted as the
> current working directory ("."), and added to the SRC args. It doesn't matter
> if the quotes come before or after any options, if it comes before "--" or if
> there are other source directories specified.
>
> This is a problem if you specify quoted bash variables on the command line and
> one of them happens to be unset.
>
> /data/cwd $ ls
> file-i-dont-want-to-copy.txt
> /data/cwd $ rsync "$UNSET_VAR" --recursive --verbose -- /data/src/ /data/dest/
> sending incremental file list
> file-i-dont-want-to-copy.txt
> file-i-want-to-copy.jpg
>
> sent 819,001 bytes  received 54 bytes  1,638,110.00 bytes/sec
> total size is 818,581  speedup is 1.00
>
> I have attached the output of the command with '--debug=ALL5' added, if it
> helps.
>