Merge branch 'sophist_fix_error_on_malformed_TRCK_tag' of git://github.com/Sophist-UK/picard into Sophist-UK-sophist_fix_error_on_malformed_TRCK_tag

Conflicts:
	NEWS.txt

NEWS.txt

@@ -36,6 +36,7 @@
  * Add %_musicbrainz_tracknumber% to hold track # as shown on MusicBrainz release web-page
    e.g. vinyl/cassette style A1, A2, B1, B2
  * Show the ID3 version of the file in the Info... dialog (Ctrl-I) (PICARD-218)
+ * Fixed a bug where Picard crashed if a MP3 file had malformed TRCK or TPOS tags (PICARD-112)
 
 
 Version 1.2 - 2013-03-30

picard/formats/id3.py

@@ -20,6 +20,7 @@
 import mutagen.apev2
 import mutagen.mp3
 import mutagen.trueaudio
+import re
 from collections import defaultdict
 from mutagen import id3
 from picard import config, log
@@ -175,6 +176,10 @@ class ID3File(File):
 
     __other_supported_tags = ("discnumber", "tracknumber",
                               "totaldiscs", "totaltracks")
+    __tag_re_parse = {
+        'TRCK': re.compile(r'^(?P<tracknumber>\d+)(?:/(?P<totaltracks>\d+))?$'),
+        'TPOS': re.compile(r'^(?P<discnumber>\d+)(?:/(?P<totaldiscs>\d+))?$')
+    }
 
     def __init__(self, filename):
         super(ID3File, self).__init__(filename)
@@ -239,18 +244,14 @@ class ID3File(File):
                 metadata.add(name, unicode(frame.text))
             elif frameid == 'UFID' and frame.owner == 'http://musicbrainz.org':
                 metadata['musicbrainz_recordingid'] = frame.data.decode('ascii', 'ignore')
-            elif frameid == 'TRCK':
-                value = frame.text[0].split('/')
-                if len(value) > 1:
-                    metadata['tracknumber'], metadata['totaltracks'] = value[:2]
+            elif frameid in self.__tag_re_parse.keys():
+                m = self.__tag_re_parse[frameid].search(frame.text[0])
+                if m:
+                    for name, value in m.groupdict().iteritems():
+                        if value is not None:
+                            metadata[name] = value
                 else:
-                    metadata['tracknumber'] = value[0]
-            elif frameid == 'TPOS':
-                value = frame.text[0].split('/')
-                if len(value) > 1:
-                    metadata['discnumber'], metadata['totaldiscs'] = value[:2]
-                else:
-                    metadata['discnumber'] = value[0]
+                    log.error("Invalid %s value '%s' dropped in %r", frameid, frame.text[0], filename)
             elif frameid == 'APIC':
                 extras = {
                     'desc': frame.desc,