ENV['RAILS_ENV] modification not taken into account by database raske tasks

The switching environment (for example from 'development' to 'test') defined in a rake task is not taken into account by database rake tasks (databases.rake)

here is an example that shows the bug :

desc 'Buggy environment switch'
task :do_sth_in_test_env do
  # we are currently in dev env and
  # we have an empty test database
  ENV['RAILS_ENV'] = 'test'
  Rake::Task['db:fixtures:load'].invoke
  # result : no fixture in the test database
end

The bug comes fom the fact that, in many tasks defined in databases.rake, the constant RAILS_ENV is used directly instead of using ENV['RAILS_ENV']

You'll find in attachment a patch that corrects this bug