Testing MongoDB with Mongoid, RSpec, and Rails

controller_spec.rb

# do our update
@controller.record_votes(winner._id.to_s, loser._id.to_s)

# will this pass or fail? who knows!?
Item.count(conditions:{ votes:1 }).should == 0

controller_spec2.rb

# do our update
@controller.record_votes(winner._id.to_s, loser._id.to_s)

# wait until we get what we want (within reason, of course)
wait_until { Item.count(conditions:{ votes:1 }) > 0 }

spec_helper.rb

RSpec.configure do |config|
# ... 
  config.before(:each) do
    db = Mongoid::Config::master
    # ignore stuff like system.indexes
    db.collection_names.reject {|c| c =~ /^system/}.each {|c| db.drop_collection c}
  end
# ...

wait_until.rb

def wait_until
  i = 0
  while !(result = yield) and i < 3 do
    sleep 1
    i += 1
  end
  raise "timed out" if !result
end