file: Fix crash when media_dirs contains non-ASCII chars

Fixes #1345

docs/changelog.rst

@@ -26,6 +26,10 @@ Bug fix release.
 - Core: Avoid endless loop if all tracks in the tracklist are unplayable and
   consume mode is off. (Fixes: :issue:`1221`, :issue:`1454`, PR: :issue:`1455`)
 
+- File: Ensure path comparision is done between bytestrings only. Fixes crash
+  where a :confval:`file/media_dirs` path contained non-ASCII characters.
+  (Fixes: :issue:`1345`, PR: :issue:`1493`)
+
 
 v2.0.0 (2016-02-15)
 ===================

mopidy/file/library.py

@@ -132,5 +132,6 @@ class FileLibraryProvider(backend.LibraryProvider):
 
     def _is_in_basedir(self, local_path):
         return any(
-            path.is_path_inside_base_dir(local_path, media_dir['path'])
+            path.is_path_inside_base_dir(
+                local_path, media_dir['path'].encode('utf-8'))
             for media_dir in self._media_dirs)

mopidy/internal/path.py

@@ -196,6 +196,11 @@ def find_mtimes(root, follow=False):
 
 
 def is_path_inside_base_dir(path, base_path):
+    if not isinstance(path, bytes):
+        raise ValueError('path is not a bytestring')
+    if not isinstance(base_path, bytes):
+        raise ValueError('base_path is not a bytestring')
+
     if path.endswith(os.sep):
         raise ValueError('Path %s cannot end with a path separator'
                          % path)

tests/internal/test_path.py

@@ -7,6 +7,8 @@ import shutil
 import tempfile
 import unittest
 
+import pytest
+
 from mopidy import compat, exceptions
 from mopidy.internal import path
 from mopidy.internal.gi import GLib
@@ -392,6 +394,30 @@ class FindMTimesTest(unittest.TestCase):
         self.assertEqual(errors, {})
 
 
+class TestIsPathInsideBaseDir(object):
+    def test_when_inside(self):
+        assert path.is_path_inside_base_dir(
+            '/æ/øå'.encode('utf-8'),
+            '/æ'.encode('utf-8'))
+
+    def test_when_outside(self):
+        assert not path.is_path_inside_base_dir(
+            '/æ/øå'.encode('utf-8'),
+            '/ø'.encode('utf-8'))
+
+    def test_byte_inside_str_fails(self):
+        with pytest.raises(ValueError):
+            path.is_path_inside_base_dir('/æ/øå'.encode('utf-8'), '/æ')
+
+    def test_str_inside_byte_fails(self):
+        with pytest.raises(ValueError):
+            path.is_path_inside_base_dir('/æ/øå', '/æ'.encode('utf-8'))
+
+    def test_str_inside_str_fails(self):
+        with pytest.raises(ValueError):
+            path.is_path_inside_base_dir('/æ/øå', '/æ')
+
+
 # TODO: kill this in favour of just os.path.getmtime + mocks
 class MtimeTest(unittest.TestCase):