Add new AnsibleK8SModule class (#269)

* Add new AnsibleK8SModule class

This class is intended to replace part of the K8SAnsibleMixin class and
is part of a larger refactoring effort.

* Fix sanity errors

* Fix unit tests

* Add mock to test requirements

tests/unit/conftest.py

@@ -0,0 +1,44 @@
+from __future__ import absolute_import, division, print_function
+
+__metaclass__ = type
+
+import json
+import sys
+from io import BytesIO
+
+import pytest
+
+import ansible.module_utils.basic
+from ansible.module_utils.six import string_types
+from ansible.module_utils._text import to_bytes
+from ansible.module_utils.common._collections_compat import MutableMapping
+
+
+@pytest.fixture
+def stdin(mocker, request):
+    old_args = ansible.module_utils.basic._ANSIBLE_ARGS
+    ansible.module_utils.basic._ANSIBLE_ARGS = None
+    old_argv = sys.argv
+    sys.argv = ["ansible_unittest"]
+
+    if isinstance(request.param, string_types):
+        args = request.param
+    elif isinstance(request.param, MutableMapping):
+        if "ANSIBLE_MODULE_ARGS" not in request.param:
+            request.param = {"ANSIBLE_MODULE_ARGS": request.param}
+        if "_ansible_remote_tmp" not in request.param["ANSIBLE_MODULE_ARGS"]:
+            request.param["ANSIBLE_MODULE_ARGS"]["_ansible_remote_tmp"] = "/tmp"
+        if "_ansible_keep_remote_files" not in request.param["ANSIBLE_MODULE_ARGS"]:
+            request.param["ANSIBLE_MODULE_ARGS"]["_ansible_keep_remote_files"] = False
+        args = json.dumps(request.param)
+    else:
+        raise Exception("Malformed data to the stdin pytest fixture")
+
+    fake_stdin = BytesIO(to_bytes(args, errors="surrogate_or_strict"))
+    mocker.patch("ansible.module_utils.basic.sys.stdin", mocker.MagicMock())
+    mocker.patch("ansible.module_utils.basic.sys.stdin.buffer", fake_stdin)
+
+    yield fake_stdin
+
+    ansible.module_utils.basic._ANSIBLE_ARGS = old_args
+    sys.argv = old_argv