config: Serialize unicode to bytes using sys.getfilesystemencoding()

mopidy/config/types.py

@@ -3,6 +3,7 @@ from __future__ import unicode_literals
 import logging
 import re
 import socket
+import sys
 
 from mopidy.utils import path
 from mopidy.config import validators
@@ -254,6 +255,8 @@ class Path(ConfigValue):
         return ExpandedPath(value, expanded)
 
     def serialize(self, value, display=False):
+        if isinstance(value, unicode):
+            value = value.encode(sys.getfilesystemencoding())
         if isinstance(value, ExpandedPath):
             return value.original
         return value

tests/config/types_test.py

@@ -5,6 +5,7 @@ from __future__ import unicode_literals
 import logging
 import mock
 import socket
+import sys
 
 from mopidy.config import types
 
@@ -364,3 +365,10 @@ class PathTest(unittest.TestCase):
     def test_serialize_plain_string(self):
         value = types.Path()
         self.assertEqual('path', value.serialize(b'path'))
+
+    def test_serialize_unicode_string(self):
+        value = types.Path()
+        expected = 'æøå'.encode(sys.getfilesystemencoding())
+        result = value.serialize('æøå')
+        self.assertEqual(expected, result)
+        self.assertIsInstance(result, bytes)