add "format" field to MediaFile for getting the file type

This allows using $format in your path format string, which is nice.

beets/library.py

@@ -60,6 +60,7 @@ ITEM_FIELDS = [
 
     ('length',      'real', False, True),
     ('bitrate',     'int',  False, True),
+    ('format',      'text', False, True),
 ]
 ITEM_KEYS_WRITABLE = [f[0] for f in ITEM_FIELDS if f[3] and f[2]]
 ITEM_KEYS_META     = [f[0] for f in ITEM_FIELDS if f[3]]

beets/mediafile.py

@@ -50,6 +50,18 @@ class FileTypeError(UnreadableFileError):
     pass
 
 
+# Constants.
+
+# Human-readable type names.
+TYPES = {
+    'mp3':  'MP3',
+    'mp4':  'AAC',
+    'ogg':  'OGG',
+    'flac': 'FLAC',
+    'ape':  'APE',
+}
+
+
 # Flags for encoding field behavior.
 
 class Enumeration(object):
@@ -660,3 +672,6 @@ class MediaFile(object):
         else:
             return self.mgfile.info.bitrate
 
+    @property
+    def format(self):
+        return TYPES[self.type]

test/test_db.py

@@ -46,6 +46,7 @@ def item(): return beets.library.Item({
     'path':        'somepath',
     'length':      60.0,
     'bitrate':     128000,
+    'format':      'FLAC',
     'mb_trackid':  'someID-1',
     'mb_albumid':  'someID-2',
     'mb_artistid': 'someID-3',
@@ -247,6 +248,11 @@ class DestinationTest(unittest.TestCase):
     def test_sanitize_replaces_colon_with_dash(self):
         p = beets.library._sanitize_path(u':', 'Darwin')
         self.assertEqual(p, u'-')
+    
+    def test_path_with_format(self):
+        self.lib.path_format = '$artist/$album ($format)'
+        p = self.lib.destination(self.i)
+        self.assert_('(FLAC)' in p)
 
 class MigrationTest(unittest.TestCase):
     """Tests the ability to change the database schema between

test/test_mediafile_basic.py

@@ -207,26 +207,31 @@ read_only_correct_dicts = {
     'full.mp3': {
         'length': 1.0,
         'bitrate': 80000,
+        'format': 'MP3',
     },
 
     'full.flac': {
         'length': 1.0,
         'bitrate': 705600,
+        'format': 'FLAC',
     },
 
     'full.m4a': {
         'length': 1.0,
         'bitrate': 64000,
+        'format': 'AAC',
     },
     
     'full.ogg': {
         'length': 1.0,
         'bitrate': 48000,
+        'format': 'OGG',
     },
     
     'full.ape': {
         'length': 1.0,
         'bitrate': 705600,
+        'format': 'APE',
     },
 
 }