From f09088df4355888641189f7019091a4d74b17bf7 Mon Sep 17 00:00:00 2001
From: Jack Wilsdon <jack.wilsdon@gmail.com>
Date: Wed, 1 May 2019 17:53:03 +0100
Subject: [PATCH] replaygain: Handle invalid XML output from bs1770gain

---
 beetsplug/replaygain.py |  9 +++++-
 test/test_replaygain.py | 62 ++++++++++++++++++++++++++++++++++-------
 2 files changed, 60 insertions(+), 11 deletions(-)

diff --git a/beetsplug/replaygain.py b/beetsplug/replaygain.py
index 4168c61b99..4a0ea064f1 100644
--- a/beetsplug/replaygain.py
+++ b/beetsplug/replaygain.py
@@ -251,7 +251,14 @@ def end_element_handler(name):
                 state['gain'] = state['peak'] = None
         parser.StartElementHandler = start_element_handler
         parser.EndElementHandler = end_element_handler
-        parser.Parse(text, True)
+
+        try:
+            parser.Parse(text, True)
+        except xml.parsers.expat.ExpatError:
+            raise ReplayGainError(
+                u'The bs1770gain tool produced malformed XML. '
+                'Using version >=0.4.10 may solve this problem.'
+            )
 
         if len(per_file_gain) != len(path_list):
             raise ReplayGainError(
diff --git a/test/test_replaygain.py b/test/test_replaygain.py
index 6ddee54dac..f750f3012f 100644
--- a/test/test_replaygain.py
+++ b/test/test_replaygain.py
@@ -19,7 +19,8 @@
 import unittest
 import six
 
-from test.helper import TestHelper, has_program
+from mock import patch
+from test.helper import TestHelper, capture_log, has_program
 
 from beets import config
 from beets.mediafile import MediaFile
@@ -44,6 +45,15 @@
     LOUDNESS_PROG_AVAILABLE = False
 
 
+def reset_replaygain(item):
+    item['rg_track_peak'] = None
+    item['rg_track_gain'] = None
+    item['rg_album_gain'] = None
+    item['rg_album_gain'] = None
+    item.write()
+    item.store()
+
+
 class ReplayGainCliTestBase(TestHelper):
 
     def setUp(self):
@@ -68,20 +78,12 @@ def setUp(self):
 
         album = self.add_album_fixture(2)
         for item in album.items():
-            self._reset_replaygain(item)
+            reset_replaygain(item)
 
     def tearDown(self):
         self.teardown_beets()
         self.unload_plugins()
 
-    def _reset_replaygain(self, item):
-        item['rg_track_peak'] = None
-        item['rg_track_gain'] = None
-        item['rg_album_gain'] = None
-        item['rg_album_gain'] = None
-        item.write()
-        item.store()
-
     def test_cli_saves_track_gain(self):
         for item in self.lib.items():
             self.assertIsNone(item.rg_track_peak)
@@ -166,6 +168,46 @@ class ReplayGainLdnsCliTest(ReplayGainCliTestBase, unittest.TestCase):
     backend = u'bs1770gain'
 
 
+class ReplayGainLdnsCliMalformedTest(TestHelper, unittest.TestCase):
+
+    @patch('beetsplug.replaygain.call')
+    def setUp(self, call_patch):
+        self.setup_beets()
+        self.config['replaygain']['backend'] = 'bs1770gain'
+
+        # Patch call to return nothing, bypassing the bs1770gain installation
+        # check.
+        call_patch.return_value = None
+        self.load_plugins('replaygain')
+
+        for item in self.add_album_fixture(2).items():
+            reset_replaygain(item)
+
+    @patch('beetsplug.replaygain.call')
+    def test_malformed_output(self, call_patch):
+        # Return malformed XML (the ampersand should be &amp;)
+        call_patch.return_value = """
+            <album>
+                <track total="1" number="1" file="&">
+                    <integrated lufs="0" lu="0" />
+                    <sample-peak spfs="0" factor="0" />
+                </track>
+            </album>
+        """
+
+        with capture_log('beets.replaygain') as logs:
+            self.run_command('replaygain')
+
+        # Count how many lines match the expected error.
+        matching = [line for line in logs if
+                    line == 'replaygain: ReplayGain error: bs1770gain '
+                            'returned malformed XML - this is a bug in '
+                            'versions prior to v0.4.10, please ensure that '
+                            'your version is up to date']
+
+        self.assertEqual(len(matching), 2)
+
+
 def suite():
     return unittest.TestLoader().loadTestsFromName(__name__)