Added a very basic test_library.py

test_library.py so far just documents existing behavior of album
objects, especially the fact that trying to access unset fields causes
an AttributeError.

test/test_library.py

@@ -0,0 +1,45 @@
+# This file is part of beets.
+# Copyright 2010, Adrian Sampson.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+# 
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+
+"""Basic tests for the objects that are used to represent the beets
+library and the items in it.
+"""
+
+import unittest
+import sys
+sys.path.append('..')
+from beets.library import BaseLibrary, BaseAlbum
+
+class AlbumTest(unittest.TestCase):
+
+    def test_field_access(self):
+        album = BaseAlbum(None, {'artist':'foo', 'albumartist':'bar'})
+        self.assertEqual(album.artist, 'foo')
+        self.assertEqual(album.albumartist, 'bar')
+
+    def test_field_access_unset_values(self):
+        """
+        This is how things work currently. Trying to access unset album
+        metadata raises an AttributeError.
+        """
+        album = BaseAlbum(None, {})
+        self.assertRaises(AttributeError, getattr, album, 'albumartist')
+        self.assertRaises(AttributeError, getattr, album, 'artist')
+
+def suite():
+    return unittest.TestLoader().loadTestsFromName(__name__)
+
+if __name__ == '__main__':
+    unittest.main(defaultTest='suite')
+