Split basic units (#33510)

Split the one monolithic test for basic.py into several files

* Split test_basic.py along categories.
  This is preliminary to get a handle on things.  Eventually we may want
  to further split it so each file is only testing a single function.
* Cleanup unused imports from splitting test_basic.py
* Port atomic_move test to pytest.
  Working on getting rid of need to maintain procenv
* Split a test of symbolic_mode_to_octal to follow unittest best practices
  Each test should only invoke the function under test once
* Port test_argument_spec to pytest.
* Fix suboptions failure

test/units/module_utils/basic/test_platform_distribution.py

@@ -0,0 +1,108 @@
+# -*- coding: utf-8 -*-
+# (c) 2012-2014, Michael DeHaan <michael.dehaan@gmail.com>
+# (c) 2016 Toshio Kuratomi <tkuratomi@ansible.com>
+# (c) 2017 Ansible Project
+# 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
+__metaclass__ = type
+
+from units.mock.procenv import ModuleTestCase
+
+from ansible.compat.tests.mock import patch
+from ansible.module_utils.six.moves import builtins
+
+realimport = builtins.__import__
+
+
+class TestPlatform(ModuleTestCase):
+    def test_module_utils_basic_get_platform(self):
+        with patch('platform.system', return_value='foo'):
+            from ansible.module_utils.basic import get_platform
+            self.assertEqual(get_platform(), 'foo')
+
+    def test_module_utils_basic_get_distribution(self):
+        from ansible.module_utils.basic import get_distribution
+
+        with patch('platform.system', return_value='Foo'):
+            self.assertEqual(get_distribution(), None)
+
+        with patch('platform.system', return_value='Linux'):
+            with patch('platform.linux_distribution', return_value=["foo"]):
+                self.assertEqual(get_distribution(), "Foo")
+
+            with patch('os.path.isfile', return_value=True):
+                with patch('platform.linux_distribution', side_effect=[("AmazonFooBar", )]):
+                    self.assertEqual(get_distribution(), "Amazonfoobar")
+
+                with patch('platform.linux_distribution', side_effect=(("", ), ("AmazonFooBam",))):
+                    self.assertEqual(get_distribution(), "Amazon")
+
+                with patch('platform.linux_distribution', side_effect=[("", ), ("", )]):
+                    self.assertEqual(get_distribution(), "OtherLinux")
+
+                def _dist(distname='', version='', id='', supported_dists=(), full_distribution_name=1):
+                    if supported_dists != ():
+                        return ("Bar", "2", "Two")
+                    else:
+                        return ("", "", "")
+
+                with patch('platform.linux_distribution', side_effect=_dist):
+                    self.assertEqual(get_distribution(), "Bar")
+
+            with patch('platform.linux_distribution', side_effect=Exception("boo")):
+                with patch('platform.dist', return_value=("bar", "2", "Two")):
+                    self.assertEqual(get_distribution(), "Bar")
+
+    def test_module_utils_basic_get_distribution_version(self):
+        from ansible.module_utils.basic import get_distribution_version
+
+        with patch('platform.system', return_value='Foo'):
+            self.assertEqual(get_distribution_version(), None)
+
+        with patch('platform.system', return_value='Linux'):
+            with patch('platform.linux_distribution', return_value=("foo", "1", "One")):
+                self.assertEqual(get_distribution_version(), "1")
+
+            with patch('os.path.isfile', return_value=True):
+                def _dist(distname='', version='', id='', supported_dists=(), full_distribution_name=1):
+                    if supported_dists != ():
+                        return ("AmazonFooBar", "2", "")
+                    else:
+                        return ("", "", "")
+
+                with patch('platform.linux_distribution', side_effect=_dist):
+                    self.assertEqual(get_distribution_version(), "2")
+
+            with patch('platform.linux_distribution', side_effect=Exception("boo")):
+                with patch('platform.dist', return_value=("bar", "3", "Three")):
+                    self.assertEqual(get_distribution_version(), "3")
+
+    def test_module_utils_basic_load_platform_subclass(self):
+        class LinuxTest:
+            pass
+
+        class Foo(LinuxTest):
+            platform = "Linux"
+            distribution = None
+
+        class Bar(LinuxTest):
+            platform = "Linux"
+            distribution = "Bar"
+
+        from ansible.module_utils.basic import load_platform_subclass
+
+        # match just the platform class, not a specific distribution
+        with patch('ansible.module_utils.basic.get_platform', return_value="Linux"):
+            with patch('ansible.module_utils.basic.get_distribution', return_value=None):
+                self.assertIs(type(load_platform_subclass(LinuxTest)), Foo)
+
+        # match both the distribution and platform class
+        with patch('ansible.module_utils.basic.get_platform', return_value="Linux"):
+            with patch('ansible.module_utils.basic.get_distribution', return_value="Bar"):
+                self.assertIs(type(load_platform_subclass(LinuxTest)), Bar)
+
+        # if neither match, the fallback should be the top-level class
+        with patch('ansible.module_utils.basic.get_platform', return_value="Foo"):
+            with patch('ansible.module_utils.basic.get_distribution', return_value=None):
+                self.assertIs(type(load_platform_subclass(LinuxTest)), LinuxTest)