Leading spaces in 'quote' cause backup to fail

[jwittkoski]

In my b2.yaml file, I had my storage defined (during testing) as:

storage:
    -   name: "b2"
        threads: 5
        quote: " -dry-run"

When running this with debug on, it fails with:

... <snip> ...
22:57:01 Beginning backup on 07-12-2020 22:57:01
22:57:01 Backing up to storage b2 with 5 threads  -dry-run
22:57:01 Executing: /usr/local/bin/duplicacy[backup -storage b2 -stats -threads 5  -dry-run]
Error executing command: exit status 3
Error: Backup failed. Check the logs for details

The log file isn't much help:

22:57:01 Beginning backup on 07-12-2020 22:57:01
22:57:01 ######################################################################
22:57:01 Backing up to storage b2 with 5 threads  -dry-run
22:57:01 Executing: /usr/local/bin/duplicacy[backup -storage b2 -stats -threads 5  -dry-run]
22:57:01 The backup command requires no arguments.
22:57:01 
22:57:01 NAME:
22:57:01    duplicacy backup - Save a snapshot of the repository to the storage
22:57:01 
22:57:01 USAGE:
22:57:01    duplicacy backup [command options]  
22:57:01 
22:57:01 OPTIONS:
22:57:01    -hash 			detect file differences by hash (rather than size and timestamp)
22:57:01    -t <tag> 			assign a tag to the backup
22:57:01    -stats 			show statistics during and after backup
22:57:01    -threads <n>			number of uploading threads
22:57:01    -limit-rate <kB/s>		the maximum upload rate (in kilobytes/sec)
22:57:01    -dry-run 			dry run for testing, don't backup anything. Use with -stats and -d
22:57:01    -vss 			enable the Volume Shadow Copy service (Windows and macOS using APFS only)
22:57:01    -vss-timeout <timeout>	the timeout in seconds to wait for the Volume Shadow Copy operation to complete
22:57:01    -storage <storage name> 	backup to the specified storage instead of the default one
22:57:01    -enum-only 			enumerate the repository recursively and then exit
22:57:01    
22:57:01 Error executing command: exit status 3

After some experimentation, it turns out that the leading space in the quote option is causing this failure.

[jwittkoski]

It's actually any leading, trailing, or multiple sequential spaces.

All of these fail:

" -dry-run"
"-dry-run "
"-dry-run   -hash"

It looks like this is due to how the code splits on spaces and turns them into command arguments for duplicacy (see https://github.com/jeffaco/duplicacy-util/blob/master/backup-ops.go#L203).

The empty "arguments" between the extra spaces are passed to duplicacy which sees the "empty" command arguments and then complains that the backup command doesn't require any arguments.