moving from with_ff to just ff (#44847)

lib/ansible/modules/utilities/logic/include_vars.py

@@ -85,8 +85,9 @@ EXAMPLES = """
   when: x == 0
 
 - name: Load a variable file based on the OS type, or a default if not found. Using free-form to specify the file.
-  include_vars: "{{ item }}"
-  with_first_found:
+  include_vars: "{{ lookup('first_found', possible_files) }}"
+  vars:
+    possible_files:
       - "{{ ansible_distribution }}.yaml"
       - "{{ ansible_os_family }}.yaml"
       - default.yaml

lib/ansible/plugins/lookup/filetree.py

@@ -12,7 +12,7 @@ short_description: recursively match all files in a directory tree
 description:
 - This lookup enables you to template a complete tree of files on a target system while retaining permissions and ownership.
 - Supports directories, files and symlinks, including SELinux and other file properties
-- If you provide more than one path, it will implement a with_first_found logic, and will not process entries it already processed in previous paths.
+- If you provide more than one path, it will implement a first_found logic, and will not process entries it already processed in previous paths.
   This enables merging different trees in order of importance, or add role_vars to specific paths to influence different instances of the same role.
 options:
   _terms:

lib/ansible/plugins/lookup/first_found.py

@@ -150,5 +150,5 @@ class LookupModule(LookupBase):
                 return [path]
         if skip:
             return []
-        raise AnsibleLookupError("No file was found when using with_first_found. Use the 'skip: true' option to allow this task to be skipped if no "
+        raise AnsibleLookupError("No file was found when using first_found. Use the 'skip: true' option to allow this task to be skipped if no "
                                  "files are found")