Run all handlers with the same `listen` topic when notified from another handler (#82364)

Fixes #82363

changelogs/fragments/82363-multiple-handlers-with-recursive-notification.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - Run all handlers with the same ``listen`` topic, even when notified from another handler (https://github.com/ansible/ansible/issues/82363).

lib/ansible/plugins/strategy/__init__.py

@@ -53,6 +53,7 @@ from ansible.template import Templar
 from ansible.utils.display import Display
 from ansible.utils.fqcn import add_internal_fqcns
 from ansible.utils.unsafe_proxy import wrap_var
+from ansible.utils.sentinel import Sentinel
 from ansible.utils.vars import combine_vars, isidentifier
 from ansible.vars.clean import strip_internal_keys, module_response_deepcopy
 
@@ -656,6 +657,7 @@ class StrategyBase:
                         # otherwise depending on the setting either error or warn
                         host_state = iterator.get_state_for_host(original_host.name)
                         for notification in result_item['_ansible_notify']:
+                            handler = Sentinel
                             for handler in self.search_handlers_by_notification(notification, iterator):
                                 if host_state.run_state == IteratingStates.HANDLERS:
                                     # we're currently iterating handlers, so we need to expand this now
@@ -666,8 +668,8 @@ class StrategyBase:
                                 else:
                                     iterator.add_notification(original_host.name, notification)
                                     display.vv(f"Notification for handler {notification} has been saved.")
-                                break
-                            else:
+                                    break
+                            if handler is Sentinel:
                                 msg = (
                                     f"The requested handler '{notification}' was not found in either the main handlers"
                                     " list nor in the listening handlers list"

test/integration/targets/handlers/runme.sh

@@ -69,6 +69,9 @@ done
 # Notify handler listen
 ansible-playbook test_handlers_listen.yml -i inventory.handlers -v "$@"
 
+# https://github.com/ansible/ansible/issues/82363
+ansible-playbook test_multiple_handlers_with_recursive_notification.yml -i inventory.handlers -v "$@"
+
 # Notify inexistent handlers results in error
 set +e
 result="$(ansible-playbook test_handlers_inexistent_notify.yml -i inventory.handlers "$@" 2>&1)"

test/integration/targets/handlers/test_multiple_handlers_with_recursive_notification.yml

@@ -0,0 +1,36 @@
+---
+- name: test multiple handlers with recursive notification
+  hosts: localhost
+  gather_facts: false
+
+  tasks:
+    - name: notify handler 1
+      command: echo
+      changed_when: true
+      notify: handler 1
+
+    - meta: flush_handlers
+
+    - name: verify handlers
+      assert:
+        that:
+          - "ran_handler_1  is defined"
+          - "ran_handler_2a is defined"
+          - "ran_handler_2b is defined"
+
+  handlers:
+    - name: handler 1
+      set_fact:
+        ran_handler_1: True
+      changed_when: true
+      notify: handler_2
+
+    - name: handler 2a
+      set_fact:
+        ran_handler_2a: True
+      listen: handler_2
+
+    - name: handler 2b
+      set_fact:
+        ran_handler_2b: True
+      listen: handler_2