Fix role completion detection problem

When the same role is listed consecutively in a play, the previous role
completion detection failed to mark it as complete as it only checked to
see if the role changed.

This patch addresses that by also keeping track of which task in the role
we are on, so that even if the same role is encountered during later passes
the task number will be less than or equal to the last noted task position.

Related to #15409

lib/ansible/compat/six/_six.py

@@ -43,6 +43,7 @@ if PY3:
     class_types = type,
     text_type = str
     binary_type = bytes
+    cmp = lambda a, b: (a > b) - (a < b)
 
     MAXSIZE = sys.maxsize
 else:
@@ -51,6 +52,7 @@ else:
     class_types = (type, types.ClassType)
     text_type = unicode
     binary_type = str
+    cmp = cmp
 
     if sys.platform.startswith("java"):
         # Jython always uses 32 bits.

lib/ansible/executor/play_iterator.py

@@ -24,6 +24,7 @@ import fnmatch
 from ansible.compat.six import iteritems
 from ansible import constants as C
 from ansible.errors import AnsibleError
+from ansible.module_utils.six import cmp
 from ansible.playbook.block import Block
 from ansible.playbook.task import Task
 from ansible.playbook.role_include import IncludeRole
@@ -48,6 +49,7 @@ class HostState:
         self.cur_rescue_task    = 0
         self.cur_always_task    = 0
         self.cur_role           = None
+        self.cur_role_task      = None
         self.cur_dep_chain      = None
         self.run_state          = PlayIterator.ITERATING_SETUP
         self.fail_state         = PlayIterator.FAILED_NONE
@@ -120,6 +122,8 @@ class HostState:
         new_state.cur_rescue_task = self.cur_rescue_task
         new_state.cur_always_task = self.cur_always_task
         new_state.cur_role = self.cur_role
+        if self.cur_role_task:
+            new_state.cur_role_task = self.cur_role_task[:]
         new_state.run_state = self.run_state
         new_state.fail_state = self.fail_state
         new_state.pending_setup = self.pending_setup
@@ -276,12 +280,53 @@ class PlayIterator:
                 parent = parent._parent
             return False
 
+        def _get_cur_task(s, depth=0):
+            res = [s.run_state, depth, s.cur_block, -1]
+            if s.run_state == self.ITERATING_TASKS:
+                if s.tasks_child_state:
+                    res = _get_cur_task(s.tasks_child_state, depth=depth+1)
+                else:
+                    res[-1] = s.cur_regular_task
+            elif s.run_state == self.ITERATING_RESCUE:
+                if s.rescue_child_state:
+                    res = _get_cur_task(s.rescue_child_state, depth=depth+1)
+                else:
+                    res[-1] = s.cur_rescue_task
+            elif s.run_state == self.ITERATING_ALWAYS:
+                if s.always_child_state:
+                    res = _get_cur_task(s.always_child_state, depth=depth+1)
+                else:
+                    res[-1] = s.cur_always_task
+            return res
+
+        def _role_task_cmp(s):
+            '''
+            tt is a tuple made of the regular/rescue/always task number
+            from the current state of the host.
+            '''
+            if not s.cur_role_task:
+                return 1
+            cur_task = _get_cur_task(s)
+            res = cmp(cur_task[0], s.cur_role_task[0])
+            if res == 0:
+                res = cmp(cur_task[1], s.cur_role_task[1])
+                if res == 0:
+                    res = cmp(cur_task[2], s.cur_role_task[2])
+                    if res == 0:
+                        res = cmp(cur_task[3], s.cur_role_task[3])
+            return res
+
         if task and task._role:
             # if we had a current role, mark that role as completed
-            if s.cur_role and _roles_are_different(task._role, s.cur_role) and host.name in s.cur_role._had_task_run and \
-               not _role_is_child(s.cur_role) and not peek:
+            if s.cur_role:
+                role_diff  = _roles_are_different(task._role, s.cur_role)
+                role_child = _role_is_child(s.cur_role)
+                tasks_cmp  = _role_task_cmp(s)
+                host_done  = host.name in s.cur_role._had_task_run
+                if (role_diff or (not role_diff and tasks_cmp <= 0)) and host_done and not role_child and not peek:
                     s.cur_role._completed[host.name] = True
             s.cur_role = task._role
+            s.cur_role_task = _get_cur_task(s)
             s.cur_dep_chain = task.get_dep_chain()
 
         if not peek:

lib/ansible/module_utils/six.py

@@ -38,6 +38,7 @@ if PY3:
     class_types = type,
     text_type = str
     binary_type = bytes
+    cmp = lambda a, b: (a > b) - (a < b)
 
     MAXSIZE = sys.maxsize
 else:
@@ -46,6 +47,7 @@ else:
     class_types = (type, types.ClassType)
     text_type = unicode
     binary_type = str
+    cmp = cmp
 
     if sys.platform.startswith("java"):
         # Jython always uses 32 bits.