Cause copy module to fail on empty string as source (#27975)

* Fail if an empty string is set as src for copy module

Fixes #27363

* Cleanup task formatting on copy tests

Use multi-line YAML
Add debug statements with verbosity: 1 rather than leave them in there commented out.

* Add test for empty string as source

* Do more checks in order to add more specific errors messages

Add more integration tests for the various failure scenarios.
Cleanup some syntax on existing integration test tasks.

lib/ansible/plugins/action/copy.py

@@ -408,12 +408,14 @@ class ActionModule(ActionBase):
         local_follow = boolean(self._task.args.get('local_follow', True), strict=False)
 
         result['failed'] = True
-        if (source is None and content is None) or dest is None:
-            result['msg'] = "src (or content) and dest are required"
-        elif source is not None and content is not None:
-            result['msg'] = "src and content are mutually exclusive"
+        if not source and content is None:
+            result['msg'] = 'src (or content) is required'
+        elif not dest:
+            result['msg'] = 'dest is required'
+        elif source and content is not None:
+            result['msg'] = 'src and content are mutually exclusive'
         elif content is not None and dest is not None and dest.endswith("/"):
-            result['msg'] = "dest must be a file if content is defined"
+            result['msg'] = "can not use content with a dir as dest"
         else:
             del result['failed']
 

test/integration/targets/copy/tasks/main.yml

@@ -10,7 +10,7 @@
         # output_dir is hardcoded in test/runner/lib/executor.py and created there
         remote_dir: '{{ output_dir }}'
 
-    - name: create remote unprivileged remote user
+    - name: Create remote unprivileged remote user
       user:
         name: '{{ remote_unprivileged_user }}'
       register: user
@@ -21,7 +21,7 @@
         state: directory
         mode: 0700
 
-    - name: 'duplicate authorized_keys'
+    - name: Duplicate authorized_keys
       copy:
         src: $HOME/.ssh/authorized_keys
         dest: '{{ user.home }}/.ssh/authorized_keys'
@@ -46,7 +46,7 @@
         state: absent
       connection: local
 
-    - name: remote unprivileged remote user
+    - name: Remote unprivileged remote user
       user:
         name: '{{ remote_unprivileged_user }}'
         state: absent