Added tests for django.utils.autoreload.

tests/utils_tests/test_autoreload.py

+import gettext
 import os
 import shutil
 import tempfile
@@ -5,10 +6,12 @@ from importlib import import_module
 
 from django import conf
 from django.contrib import admin
-from django.test import SimpleTestCase, override_settings
+from django.test import SimpleTestCase, mock, override_settings
 from django.test.utils import extend_sys_path
 from django.utils import autoreload
 from django.utils._os import npath
+from django.utils.six.moves import _thread
+from django.utils.translation import trans_real
 
 LOCALE_PATH = os.path.join(os.path.dirname(__file__), 'locale')
 
@@ -184,3 +187,67 @@ class TestFilenameGenerator(SimpleTestCase):
             with self.assertRaises(Exception):
                 autoreload.check_errors(import_module)('test_exception')
         self.assertFileFound(filename)
+
+
+class CleanFilesTests(SimpleTestCase):
+    TEST_MAP = {
+        # description: (input_file_list, expected_returned_file_list)
+        'falsies': ([None, False], []),
+        'pycs': (['myfile.pyc'], ['myfile.py']),
+        'pyos': (['myfile.pyo'], ['myfile.py']),
+        '$py.class': (['myclass$py.class'], ['myclass.py']),
+        'combined': (
+            [None, 'file1.pyo', 'file2.pyc', 'myclass$py.class'],
+            ['file1.py', 'file2.py', 'myclass.py'],
+        )
+    }
+
+    def _run_tests(self, mock_files_exist=True):
+        with mock.patch('django.utils.autoreload.os.path.exists', return_value=mock_files_exist):
+            for description, values in self.TEST_MAP.items():
+                filenames, expected_returned_filenames = values
+                self.assertEqual(
+                    autoreload.clean_files(filenames),
+                    expected_returned_filenames if mock_files_exist else [],
+                    msg='{} failed for input file list: {}; returned file list: {}'.format(
+                        description, filenames, expected_returned_filenames
+                    ),
+                )
+
+    def test_files_exist(self):
+        """
+        If the file exists, any compiled files (pyc, pyo, $py.class) are
+        transformed as their source files.
+        """
+        self._run_tests()
+
+    def test_files_do_not_exist(self):
+        """
+        If the files don't exist, they aren't in the returned file list.
+        """
+        self._run_tests(mock_files_exist=False)
+
+
+class ResetTranslationsTests(SimpleTestCase):
+
+    def setUp(self):
+        self.gettext_translations = gettext._translations.copy()
+        self.trans_real_translations = trans_real._translations.copy()
+
+    def tearDown(self):
+        gettext._translations = self.gettext_translations
+        trans_real._translations = self.trans_real_translations
+
+    def test_resets_gettext(self):
+        gettext._translations = {'foo': 'bar'}
+        autoreload.reset_translations()
+        self.assertEqual(gettext._translations, {})
+
+    def test_resets_trans_real(self):
+        trans_real._translations = {'foo': 'bar'}
+        trans_real._default = 1
+        trans_real._active = False
+        autoreload.reset_translations()
+        self.assertEqual(trans_real._translations, {})
+        self.assertIsNone(trans_real._default)
+        self.assertIsInstance(trans_real._active, _thread._local)