1  # -*- coding: utf-8 -*-
   2  """Tests for CommandChainDispatcher."""
   3  
   4  
   5  #-----------------------------------------------------------------------------
   6  # Imports
   7  #-----------------------------------------------------------------------------
   8  
   9  import pytest
  10  from IPython.core.error import TryNext
  11  from IPython.core.hooks import CommandChainDispatcher
  12  
  13  #-----------------------------------------------------------------------------
  14  # Local utilities
  15  #-----------------------------------------------------------------------------
  16  
  17  # Define two classes, one which succeeds and one which raises TryNext. Each
  18  # sets the attribute `called` to True when it is called.
  19  class Okay(object):
  20      def __init__(self, message):
  21          self.message = message
  22          self.called = False
  23      def __call__(self):
  24          self.called = True
  25          return self.message
  26  
  27  class Fail(object):
  28      def __init__(self, message):
  29          self.message = message
  30          self.called = False
  31      def __call__(self):
  32          self.called = True
  33          raise TryNext(self.message)
  34  
  35  #-----------------------------------------------------------------------------
  36  # Test functions
  37  #-----------------------------------------------------------------------------
  38  
  39  def test_command_chain_dispatcher_ff():
  40      """Test two failing hooks"""
  41      fail1 = Fail("fail1")
  42      fail2 = Fail("fail2")
  43      dp = CommandChainDispatcher([(0, fail1), (10, fail2)])
  44  
  45      with pytest.raises(TryNext) as e:
  46          dp()
  47      assert str(e.value) == "fail2"
  48  
  49      assert fail1.called is True
  50      assert fail2.called is True
  51  
  52  def test_command_chain_dispatcher_fofo():
  53      """Test a mixture of failing and succeeding hooks."""
  54      fail1 = Fail("fail1")
  55      fail2 = Fail("fail2")
  56      okay1 = Okay("okay1")
  57      okay2 = Okay("okay2")
  58  
  59      dp = CommandChainDispatcher([(0, fail1),
  60                                   # (5, okay1), # add this later
  61                                   (10, fail2),
  62                                   (15, okay2)])
  63      dp.add(okay1, 5)
  64  
  65      assert dp() == "okay1"
  66  
  67      assert fail1.called is True
  68      assert okay1.called is True
  69      assert fail2.called is False
  70      assert okay2.called is False
  71  
  72  def test_command_chain_dispatcher_eq_priority():
  73      okay1 = Okay(u'okay1')
  74      okay2 = Okay(u'okay2')
  75      dp = CommandChainDispatcher([(1, okay1)])
  76      dp.add(okay2, 1)
  77