added handlers_from (#49220)

* added handlers_from

fixes #46769

test/integration/targets/handlers/from_handlers.yml

@@ -0,0 +1,41 @@
+- name: verify handlers_from on include_role
+  hosts: A
+  gather_facts: False
+  connection: local
+  tags: ['scenario1']
+  tasks:
+    - name: test include_role
+      include_role: name=test_handlers_meta handlers_from=alternate.yml
+
+    - name: force handler run
+      meta: flush_handlers
+
+    - name: verify handlers ran
+      assert:
+        that:
+            - "'handler1_alt_called' in hostvars[inventory_hostname]"
+            - "'handler2_alt_called' in hostvars[inventory_hostname]"
+      tags: ['scenario1']
+
+
+- name: verify handlers_from on import_role
+  hosts: A
+  gather_facts: False
+  connection: local
+  tasks:
+    - name: set facts to false
+      set_fact:
+        handler1_alt_called: False
+        handler2_alt_called: False
+
+    - import_role: name=test_handlers_meta handlers_from=alternate.yml
+
+    - name: force handler run
+      meta: flush_handlers
+
+    - name: verify handlers ran
+      assert:
+        that:
+            - handler1_alt_called|bool
+            - handler2_alt_called|bool
+      tags: ['scenario1']

test/integration/targets/handlers/roles/test_handlers_meta/handlers/alternate.yml

@@ -0,0 +1,12 @@
+- name: set_handler_fact_1
+  set_fact:
+    handler1_called: True
+    handler1_alt_called: True
+
+- name: set_handler_fact_2
+  set_fact:
+    handler2_called: True
+    handler2_alt_called: True
+
+- name: count_handler
+  shell: echo . >> {{ handler_countpath }}

test/integration/targets/handlers/runme.sh

@@ -2,7 +2,12 @@
 
 set -eux
 
+# simple handler test
 ansible-playbook test_handlers.yml -i inventory.handlers -v "$@" --tags scenario1
+
+# simple from_handlers test
+ansible-playbook from_handlers.yml -i inventory.handlers -v "$@" --tags scenario1
+
 ansible-playbook test_listening_handlers.yml -i inventory.handlers -v "$@"
 
 [ "$(ansible-playbook test_handlers.yml -i inventory.handlers -v "$@" --tags scenario2 -l A \