Fix missing delegate display

changelogs/fragments/restore_delegate_label.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - callbacks, restore displaying delegation to host as host label.

lib/ansible/executor/task_executor.py

@@ -728,6 +728,11 @@ def _evaluate_failed_when_result(result):
             for k in plugin_vars:
                 result["_ansible_delegated_vars"][k] = cvars.get(k)
 
+            # note: here for callbacks that rely on this info to display delegation
+            for requireshed in ('ansible_host', 'ansible_port', 'ansible_user', 'ansible_connection'):
+                if requireshed not in result["_ansible_delegated_vars"] and requireshed in cvars:
+                    result["_ansible_delegated_vars"][requireshed] = cvars.get(requireshed)
+
         # and return
         display.debug("attempt loop complete, returning result")
         return result

lib/ansible/plugins/callback/__init__.py

@@ -21,9 +21,7 @@
 
 import difflib
 import json
-import os
 import sys
-import warnings
 
 from copy import deepcopy
 
@@ -104,11 +102,15 @@ def host_label(result):
         """Return label for the hostname (& delegated hostname) of a task
         result.
         """
-        hostname = result._host.get_name()
-        delegated_vars = result._result.get('_ansible_delegated_vars', None)
-        if delegated_vars:
-            return "%s -> %s" % (hostname, delegated_vars['ansible_host'])
-        return "%s" % (hostname,)
+        label = "%s" % result._host.get_name()
+        if result._task.delegate_to and result._task.delegate_to != result._host.get_name():
+            # show delegated host
+            label += " -> %s" % result._task.delegate_to
+            # in case we have 'extra resolution'
+            ahost = result._result.get('_ansible_delegated_vars', {}).get('ansible_host', result._task.delegate_to)
+            if result._task.delegate_to != ahost:
+                label += "(%s)" % ahost
+        return label
 
     def _run_is_verbose(self, result, verbosity=0):
         return ((self._display.verbosity > verbosity or result._result.get('_ansible_verbose_always', False) is True)

test/units/plugins/callback/test_callback.py

@@ -32,6 +32,10 @@
 from ansible.plugins.callback import CallbackBase
 
 
+mock_task = MagicMock()
+mock_task.delegate_to = None
+
+
 class TestCallback(unittest.TestCase):
     # FIXME: This doesn't really test anything...
     def test_init(self):
@@ -50,13 +54,15 @@ def test_display_verbose(self):
         self.assertIs(cb._display, display_mock)
 
     def test_host_label(self):
-        result = TaskResult(host=Host('host1'), task=None, return_data={})
+        result = TaskResult(host=Host('host1'), task=mock_task, return_data={})
+
         self.assertEquals(CallbackBase.host_label(result), 'host1')
 
     def test_host_label_delegated(self):
+        mock_task.delegate_to = 'host2'
         result = TaskResult(
             host=Host('host1'),
-            task=None,
+            task=mock_task,
             return_data={'_ansible_delegated_vars': {'ansible_host': 'host2'}},
         )
         self.assertEquals(CallbackBase.host_label(result), 'host1 -> host2')