module ActiveSupport::Testing::Deprecation

def collect_deprecations
  old_behavior = ActiveSupport::Deprecation.behavior
  deprecations = []
  ActiveSupport::Deprecation.behavior = Proc.new do |message, callstack|
    deprecations << message
  end
  result = yield
  [result, deprecations]
ensure
  ActiveSupport::Deprecation.behavior = old_behavior
end