call

# File activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb, line 470
      def call(env)
        testing = env.key?('rack.test')

        status, headers, body = @app.call(env)

        [status, headers, Proxy.new(body, testing)]
      rescue
        ActiveRecord::Base.clear_active_connections! unless testing
        raise
      end