Deploy a specific or the current Git branch by default using Capistrano

deploy.rb

# parses out the current branch you're on. See: http://www.harukizaemon.com/2008/05/deploying-branches-with-capistrano.html
current_branch = `git branch`.match(/\* (\S+)\s/m)[1]

# use the branch specified as a param, then use the current branch. If all fails use master branch
set :branch, ENV['branch'] || current_branch || "master" # you can use the 'branch' parameter on deployment to specify the branch you wish to deploy

`git rev-parse --abbrev-ref HEAD`.strip