Add mopidy.utils.path.mtime helper that is easily faked in tests

mopidy/utils/path.py

@@ -54,3 +54,20 @@ def find_files(path):
             for filename in filenames:
                 dirpath = os.path.abspath(dirpath)
                 yield os.path.join(dirpath, filename)
+
+class Mtime(object):
+    def __init__(self):
+        self.fake = None
+
+    def __call__(self, path):
+        if self.fake is not None:
+            return self.fake
+        return int(os.stat(path).st_mtime)
+
+    def set_fake_time(self, time):
+        self.fake = time
+
+    def undo_fake(self):
+        self.fake = None
+
+mtime = Mtime()

tests/utils/path_test.py

@@ -6,7 +6,7 @@ import sys
 import tempfile
 import unittest
 
-from mopidy.utils.path import (get_or_create_folder,
+from mopidy.utils.path import (get_or_create_folder, mtime,
     path_to_uri, uri_to_path, split_path, find_files)
 
 from tests import SkipTest, data_folder
@@ -135,3 +135,16 @@ class FindFilesTest(unittest.TestCase):
 
     def test_expanduser(self):
         raise SkipTest
+
+
+class MtimeTest(unittest.TestCase):
+    def tearDown(self):
+        mtime.undo_fake()
+
+    def test_mtime_of_current_dir(self):
+        mtime_dir = int(os.stat('.').st_mtime)
+        self.assertEqual(mtime_dir, mtime('.'))
+
+    def test_fake_time_is_returned(self):
+        mtime.set_fake_time(123456)
+        self.assertEqual(mtime('.'), 123456)