MH DeprecateAttrsMixin (#3727)

* initial commit for deprecate_attrs

* completed tests

* added spaces

* test now works when tehre is more than one deprecation

* trying == instead of eq in jinja

* new approach to testing

* removed extraneous debug message

tests/integration/targets/module_helper/library/msimpleda.py

@@ -0,0 +1,64 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+# (c) 2021, Alexei Znamensky <russoz@gmail.com>
+#
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+import collections
+__metaclass__ = type
+
+DOCUMENTATION = '''
+module: msimpleda
+author: "Alexei Znamensky (@russoz)"
+short_description: Simple module for testing DeprecationAttrsMixin
+description:
+  - Simple module test description.
+options:
+  a:
+    description: aaaa
+    type: int
+'''
+
+EXAMPLES = ""
+
+RETURN = ""
+
+from ansible_collections.community.general.plugins.module_utils.module_helper import ModuleHelper
+from ansible_collections.community.general.plugins.module_utils.mh.mixins.deprecate_attrs import DeprecateAttrsMixin
+
+
+class MSimpleDA(DeprecateAttrsMixin, ModuleHelper):
+    output_params = ('a',)
+    module = dict(
+        argument_spec=dict(
+            a=dict(type='int'),
+        ),
+    )
+
+    attr1 = "abc"
+    attr2 = "def"
+
+    def __init_module__(self):
+        self._deprecate_attr(
+            "attr2",
+            msg="Attribute attr2 is deprecated",
+            version="9.9.9",
+            collection_name="community.general",
+            target=self.__class__,
+            module=self.module,
+        )
+
+    def __run__(self):
+        if self.vars.a == 1:
+            self.vars.attr1 = self.attr1
+        if self.vars.a == 2:
+            self.vars.attr2 = self.attr2
+
+
+def main():
+    MSimpleDA.execute()
+
+
+if __name__ == '__main__':
+    main()