new_contents: import json
  from mock import patch
  import unittest
  
  from sure import expect
  
  from simpleflow.swf.helpers import swf_identity
  
  
  @patch("socket.gethostname")
  @patch("getpass.getuser")
  @patch("os.getpid")
  class TestSwfHelpers(unittest.TestCase):
      def test_swf_identity_standard_case(self, mock_pid, mock_user, mock_host):
          mock_host.return_value = "foo.example.com"
          mock_user.return_value = "root"
          mock_pid.return_value = 1234
  
          expect(
              json.loads(swf_identity())
          ).to.equal({
              "hostname": "foo.example.com",
              "user": "root",
              "pid": 1234,
          })
  
      def test_swf_identity_truncated(self, mock_pid, mock_user, mock_host):
          """
          The result should be truncated to 256 characters. Producing an invalid
          JSON string is better than producing an invalid SWF response (for now).
          Later we might externalize this another way (think Data Converters).
          """
          mock_host.return_value = "a" * 250
          mock_user.return_value = "root"
          mock_pid.return_value = 1234
  
          expect(swf_identity()).to.have.length_of(256)
  
subject: Add basic tests for swf_identity() helper