One Database Per Branch, Per Environment

boot.rb

CURRENT_BRANCH = `git status | head -1`.to_s.gsub('On branch ','').chomp

database.yml

<% 
database_prefix = 'workable'
environments = %W( development test ) 
%>

defaults: &defaults
  pool: 5
  adapter: mysql2
  encoding: utf8
  reconnect: false
  username: root
  password: 
  host: localhost
  
<% environments.each do |environment| %>
<%= environment %>:
  <<: *defaults
  database: <%= [ database_prefix, CURRENT_BRANCH ].join('_').underscore %>
<% end %>