From e215484c75e3205cb7af27a5e5b58bc4552efd5d Mon Sep 17 00:00:00 2001
From: Stein Magnus Jodal <stein.magnus@jodal.no>
Date: Fri, 30 Mar 2018 11:25:13 +0200
Subject: [PATCH] encoding: Never crash if unknown bytes in OS errors

Fixes #1599
---
 docs/changelog.rst              | 4 ++++
 mopidy/internal/encoding.py     | 2 +-
 tests/internal/test_encoding.py | 7 +++++++
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index af4f9b04..782b6281 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -22,6 +22,10 @@ Feature release.
 - MPD: Added Unix domain sockets for binding MPD to.
   (Fixes: :issue:`1531`, PR: :issue:`1629`)
 
+- Ensure that decoding of OS errors with unknown encoding never crashes, but
+  instead replaces unknown bytes with a replacement marker. (Fixes:
+  :issue:`1599`)
+
 
 v2.1.0 (2017-01-02)
 ===================
diff --git a/mopidy/internal/encoding.py b/mopidy/internal/encoding.py
index 27506816..d7d0dbdf 100644
--- a/mopidy/internal/encoding.py
+++ b/mopidy/internal/encoding.py
@@ -9,4 +9,4 @@ def locale_decode(bytestr):
     try:
         return compat.text_type(bytestr)
     except UnicodeError:
-        return bytes(bytestr).decode(locale.getpreferredencoding())
+        return bytes(bytestr).decode(locale.getpreferredencoding(), 'replace')
diff --git a/tests/internal/test_encoding.py b/tests/internal/test_encoding.py
index 98e982b8..91f17047 100644
--- a/tests/internal/test_encoding.py
+++ b/tests/internal/test_encoding.py
@@ -43,3 +43,10 @@ class LocaleDecodeTest(unittest.TestCase):
         encoding.locale_decode(b'abc')
 
         self.assertFalse(mock.called)
+
+    def test_replaces_unknown_bytes_instead_of_crashing(self, mock):
+        mock.return_value = 'US-ASCII'
+
+        result = encoding.locale_decode(b'abc\xc3def')
+
+        assert result == 'abc\ufffddef'