borg mount fails silently on trailing spaces

[nemoinis]

Your borg version (borg -V).

borg 1.1.8

Operating system (distribution) and version.

Debian buster

Full borg commandline that lead to the problem (leave away excludes and passwords)

borg mount --prefix clientname /path/to/repo emptydir ""

Describe the problem you're observing.

borg mount silently fails when a command contains trailing spaces, as the one above. Of course I do not type such commands, but they occur as the result of bash scripts expansion of empty parameters, for example.

borg mount does mount the repo and the archives appear in 'emptydir', but they are all empty.

[ThomasWaldmann]

IIRC, any trailing arguments will be interpreted to match archive contents. So, if you give the empty string there, it won't match anything.

[ThomasWaldmann]

Reproduced with borg 1.2.4+.

This is done in _process_archive, paths are all arguments after the mountpoint.

        matcher = Archiver.build_matcher(self._args.patterns, self._args.paths)

[ThomasWaldmann]

This issue is just one of multiple issues, other commands could also be strangely affected:

• create
• extract
• recreate
• diff
• export-tar

This is why I used type=PathSpec instead of type=str in the argparser setup, it simply rejects empty strings.

[ThomasWaldmann]

borg 1.4 is fixed by #8005.