role argspec - tag role argspec validation task with 'always' (#74994) (#74996)

* update tag docs

(cherry picked from commit 97acb0f470)

changelogs/fragments/role_argspec_tagged_always.yml

@@ -0,0 +1,2 @@
+bugfixes:
+    - roles - make sure argspec validation task is tagged with ``always`` (https://github.com/ansible/ansible/pull/74994).

docs/docsite/rst/user_guide/playbooks_tags.rst

@@ -305,6 +305,10 @@ For example:
      you apply a tag and then use a different tag in ``--tags`` or the same
      tag in ``--skip-tags``.
 
+.. warning::
+   * The role argument specification validation task is tagged with 'always' by default. This validation
+     will be skipped if you use ``--skip-tags always``.
+
 .. versionadded:: 2.5
 
 If you assign the ``never`` tag to a task or play, Ansible will skip that task or play unless you specifically request it (``--tags never``).

lib/ansible/playbook/role/__init__.py

@@ -358,6 +358,7 @@ class Role(Base, Conditional, Taggable, CollectionSearch):
                 },
             },
             'name': task_name,
+            'tags': ['always'],
         }
 
     def _load_role_yaml(self, subdir, main=None, allow_dir=False):

test/integration/targets/roles_arg_spec/runme.sh

@@ -25,3 +25,8 @@ set +e
 ansible-playbook test_play_level_role_fails.yml -i ../../inventory "$@"
 test $? -ne 0
 set -e
+
+# Test the validation task is tagged with 'always' by specifying an unused tag.
+# The task is tagged with 'foo' but we use 'bar' in the call below and expect
+# the validation task to run anyway since it is tagged 'always'.
+ansible-playbook test_tags.yml -i ../../inventory "$@" --tags bar | grep "a : Validating arguments against arg spec 'main' - Main entry point for role A."

test/integration/targets/roles_arg_spec/test_tags.yml

@@ -0,0 +1,11 @@
+---
+- hosts: localhost
+  gather_facts: false
+  tasks:
+      - name: "Tag test #1"
+        import_role:
+            name: a
+        vars:
+            a_str: "tag test #1"
+        tags:
+            - foo