Adding keep number causes cycler to fail

[MattCastellana]

Just set up backup for the first time, ran the default generator and set up a simple backup, ran it and got this error:

[2015/10/08 19:32:41][info] Storage::Local Started...
[2015/10/08 19:32:41][info] Storing '/Users/Matthew/backups/my_backup/2015.10.08.19.31.35/my_backup.tar'...
[2015/10/08 19:32:41][info] Cycling Started...
[2015/10/08 19:32:41][error] Model::Error: Backup for Description for my_backup (my_backup) Failed!
[2015/10/08 19:32:41][error] --- Wrapped Exception ---
[2015/10/08 19:32:41][error] ArgumentError: negative array size
[2015/10/08 19:32:41][error]
[2015/10/08 19:32:41][error] Backtrace:
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/storage/cycler.rb:25:in `last'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/storage/cycler.rb:25:in `cycle!'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/storage/base.rb:47:in `perform!'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:334:in `block in store!'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:332:in `map'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:332:in `store!'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:306:in `block in procedures'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:269:in `call'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:269:in `block in perform!'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:268:in `each'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/model.rb:268:in `perform!'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/lib/backup/cli.rb:156:in `perform'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/thor-0.18.1/lib/thor/command.rb:27:in `run'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/thor-0.18.1/lib/thor/invocation.rb:120:in `invoke_command'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/thor-0.18.1/lib/thor.rb:363:in `dispatch'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/thor-0.18.1/lib/thor/base.rb:439:in `start'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/gems/backup-4.2.1/bin/backup:5:in `<top (required)>'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/bin/backup:23:in `load'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/bin/backup:23:in `<main>'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/bin/ruby_executable_hooks:15:in `eval'
[2015/10/08 19:32:41][error]   /Users/Matthew/.rvm/gems/ruby-2.2.1/bin/ruby_executable_hooks:15:in `<main>'

After some debug, I found that the local.keep = 5 command was failing. I've tried it with different numbers, same result. If I disable the keep completely, the backup works perfectly.

Not sure if this is an issue with my configuration, or if this is a bug. Considering this is a very simple backup, I assume it's a bug.

My specs: Mac OSX 10.11 El Capitan, Backup 4.2.1 : ruby 2.2.1p85 (2015-02-26 revision 49769) [x86_64-darwin14]

My backup file:

# encoding: utf-8

##
# Backup Generated: my_backup
# Once configured, you can run the backup with the following command:
#
# $ backup perform -t my_backup [-c <path_to_configuration_file>]
#
# For more information about Backup's components, see the documentation at:
# http://backup.github.io/backup
#
Model.new(:my_backup, 'Description for my_backup') do

  archive :my_archive do |archive|
    archive.root '~'
    archive.add "rails/misc/"
  end

  store_with Local do |local|
    local.path       = "~/backups/"
    local.keep       = 5
  end

  compress_with Gzip
end

[demetrodon]

I have this error too, when I'm trying analogy configuration.
My specs: ubuntu 14.04, Backup 4.2.1, ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-linux]

[tombruijn]

I see where it's coming from. I'll fix it when I get home. For now you can use version 4.2.0 where it works.

[jamesjefferies]

I am experiencing this with db.keep being set in the dropbox configuration.
My specs: ubuntu 14.04, Backup 4.2.1, ruby 2.2.3p173 (2015-08-18 revision 51636) [x86_64-linux]

I think that in the cycler.rb file, the cycle! method needs to check whether the excess is > 0 before setting cycled packages.

Locally I tried that (and reset my Dropbox location) and it then works and cycles correctly.

[tombruijn]

I yanked 4.2.1 and will work on a fix

[jamesjefferies]

Thanks @tombruijn - I was just forking to create a pull request, but I will stop for now :)

[tombruijn]

@jamesjefferies I'm not saying that you shouldn't make a PR. Makes my live a little bit easier ;)

[jamesjefferies]

@tombruijn hope this PR makes your life a little bit easier ;)

[tombruijn]

Closed by #712

Released v4.2.2 with the fix