diff --git a/beets/mediafile.py b/beets/mediafile.py
index 7d1b07280..9db6ba4db 100644
--- a/beets/mediafile.py
+++ b/beets/mediafile.py
@@ -56,15 +56,13 @@ import imghdr
 import os
 import traceback
 import enum
-
-from beets import logging
-from beets.util import displayable_path, syspath, as_string
+import logging
 import six
 
 
 __all__ = ['UnreadableFileError', 'FileTypeError', 'MediaFile']
 
-log = logging.getLogger('beets')
+log = logging.getLogger(__name__)
 
 # Human-readable type names.
 TYPES = {
@@ -90,7 +88,7 @@ class UnreadableFileError(Exception):
     """Mutagen is not able to extract information from the file.
     """
     def __init__(self, path):
-        Exception.__init__(self, displayable_path(path))
+        Exception.__init__(self, repr(path))
 
 
 class FileTypeError(UnreadableFileError):
@@ -100,11 +98,10 @@ class FileTypeError(UnreadableFileError):
     mutagen type is not supported by `Mediafile`.
     """
     def __init__(self, path, mutagen_type=None):
-        path = displayable_path(path)
         if mutagen_type is None:
-            msg = path
+            msg = repr(path)
         else:
-            msg = u'{0}: of mutagen type {1}'.format(path, mutagen_type)
+            msg = u'{0}: of mutagen type {1}'.format(repr(path), mutagen_type)
         Exception.__init__(self, msg)
 
 
@@ -112,7 +109,7 @@ class MutagenError(UnreadableFileError):
     """Raised when Mutagen fails unexpectedly---probably due to a bug.
     """
     def __init__(self, path, mutagen_exc):
-        msg = u'{0}: {1}'.format(displayable_path(path), mutagen_exc)
+        msg = u'{0}: {1}'.format(repr(path), mutagen_exc)
         Exception.__init__(self, msg)
 
 
@@ -134,12 +131,12 @@ def mutagen_call(action, path, func, *args, **kwargs):
     try:
         return func(*args, **kwargs)
     except mutagen.MutagenError as exc:
-        log.debug(u'{} failed: {}', action, six.text_type(exc))
+        log.debug(u'%s failed: %s', action, six.text_type(exc))
         raise UnreadableFileError(path)
     except Exception as exc:
         # Isolate bugs in Mutagen.
-        log.debug(u'{}', traceback.format_exc())
-        log.error(u'uncaught Mutagen exception in {}: {}', action, exc)
+        log.debug(u'%s', traceback.format_exc())
+        log.error(u'uncaught Mutagen exception in %s: %s', action, exc)
         raise MutagenError(path, exc)
 
 
@@ -405,7 +402,7 @@ class Image(object):
             try:
                 type = list(ImageType)[type]
             except IndexError:
-                log.debug(u"ignoring unknown image type index {0}", type)
+                log.debug(u"ignoring unknown image type index %s", type)
                 type = ImageType.other
         self.type = type
 
@@ -1412,7 +1409,6 @@ class MediaFile(object):
         By default, MP3 files are saved with ID3v2.4 tags. You can use
         the older ID3v2.3 standard by specifying the `id3v23` option.
         """
-        path = syspath(path)
         self.path = path
 
         self.mgfile = mutagen_call('open', path, mutagen.File, path)
@@ -1488,7 +1484,12 @@ class MediaFile(object):
         """
         for property, descriptor in cls.__dict__.items():
             if isinstance(descriptor, MediaField):
-                yield as_string(property)
+                if isinstance(property, bytes):
+                    # On Python 2, class field names are bytes. This method
+                    # produces text strings.
+                    yield property.decode('utf8', 'ignore')
+                else:
+                    yield property
 
     @classmethod
     def _field_sort_name(cls, name):
diff --git a/beetsplug/badfiles.py b/beetsplug/badfiles.py
index bb14c7762..5ab0ae983 100644
--- a/beetsplug/badfiles.py
+++ b/beetsplug/badfiles.py
@@ -105,7 +105,7 @@ class BadFiles(BeetsPlugin):
                 ui.print_(u"{}: checker exited withs status {}"
                           .format(ui.colorize('text_error', dpath), status))
                 for line in output:
-                    ui.print_("  {}".format(displayable_path(line)))
+                    ui.print_(u"  {}".format(displayable_path(line)))
             elif errors > 0:
                 ui.print_(u"{}: checker found {} errors or warnings"
                           .format(ui.colorize('text_warning', dpath), errors))
diff --git a/docs/changelog.rst b/docs/changelog.rst
index 17024badb..22e453f57 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -4,7 +4,9 @@ Changelog
 1.4.2 (in development)
 ----------------------
 
-Changelog goes here!
+Fixes:
+
+* :doc:`/plugins/badfiles`: Fix a crash on non-ASCII filenames. :bug:`2299`
 
 
 1.4.1 (November 25, 2016)
diff --git a/docs/plugins/fetchart.rst b/docs/plugins/fetchart.rst
index c839b90ba..7eb8c194e 100644
--- a/docs/plugins/fetchart.rst
+++ b/docs/plugins/fetchart.rst
@@ -60,7 +60,7 @@ file. The available options are:
   Default: None.
 - **google_engine**: The custom search engine to use.
   Default: The `beets custom search engine`_, which searches the entire web.
-  **fanarttv_key**: The personal API key for requesting art from
+- **fanarttv_key**: The personal API key for requesting art from
   fanart.tv. See below.
 - **store_source**: If enabled, fetchart stores the artwork's source in a
   flexible tag named ``art_source``. See below for the rationale behind this.
diff --git a/docs/plugins/web.rst b/docs/plugins/web.rst
index b267af9d2..f4ae063e0 100644
--- a/docs/plugins/web.rst
+++ b/docs/plugins/web.rst
@@ -72,7 +72,7 @@ The Web backend is built using a simple REST+JSON API with the excellent
 `Backbone.js`_. This allows future non-Web clients to use the same backend API.
 
 .. _Flask: http://flask.pocoo.org/
-.. _Backbone.js: http://documentcloud.github.com/backbone/
+.. _Backbone.js: http://backbonejs.org
 
 Eventually, to make the Web player really viable, we should use a Flash fallback
 for unsupported formats/browsers. There are a number of options for this:
diff --git a/test/_common.py b/test/_common.py
index 09747e595..597f0dc38 100644
--- a/test/_common.py
+++ b/test/_common.py
@@ -333,6 +333,29 @@ class Bag(object):
         return self.fields.get(key)
 
 
+# Convenience methods for setting up a temporary sandbox directory for tests
+# that need to interact with the filesystem.
+
+class TempDirMixin(object):
+    """Text mixin for creating and deleting a temporary directory.
+    """
+
+    def create_temp_dir(self):
+        """Create a temporary directory and assign it into `self.temp_dir`.
+        Call `remove_temp_dir` later to delete it.
+        """
+        path = tempfile.mkdtemp()
+        if not isinstance(path, bytes):
+            path = path.encode('utf8')
+        self.temp_dir = path
+
+    def remove_temp_dir(self):
+        """Delete the temporary directory created by `create_temp_dir`.
+        """
+        if os.path.isdir(self.temp_dir):
+            shutil.rmtree(self.temp_dir)
+
+
 # Platform mocking.
 
 @contextmanager
diff --git a/test/test_acousticbrainz.py b/test/test_acousticbrainz.py
index 82a69c527..0b1407581 100644
--- a/test/test_acousticbrainz.py
+++ b/test/test_acousticbrainz.py
@@ -16,12 +16,13 @@
 """Tests for the 'acousticbrainz' plugin.
 """
 
-from __future__ import absolute_import, print_function
+from __future__ import division, absolute_import, print_function
 
 import json
 import os.path
+import unittest
 
-from test._common import unittest, RSRC
+from test._common import RSRC
 
 from beetsplug.acousticbrainz import AcousticPlugin, ABSCHEME
 
diff --git a/test/test_art.py b/test/test_art.py
index 5c3a4d7e9..aba180780 100644
--- a/test/test_art.py
+++ b/test/test_art.py
@@ -19,12 +19,12 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import shutil
+import unittest
 
 import responses
 from mock import patch
 
 from test import _common
-from test._common import unittest
 from beetsplug import fetchart
 from beets.autotag import AlbumInfo, AlbumMatch
 from beets import config
diff --git a/test/test_autotag.py b/test/test_autotag.py
index b2f3fd61d..6f107afa4 100644
--- a/test/test_autotag.py
+++ b/test/test_autotag.py
@@ -19,9 +19,9 @@ from __future__ import division, absolute_import, print_function
 
 import re
 import copy
+import unittest
 
 from test import _common
-from test._common import unittest
 from beets import autotag
 from beets.autotag import match
 from beets.autotag.hooks import Distance, string_dist
diff --git a/test/test_bucket.py b/test/test_bucket.py
index daade86ad..61f6cfe24 100644
--- a/test/test_bucket.py
+++ b/test/test_bucket.py
@@ -17,7 +17,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from beetsplug import bucket
 from beets import config, ui
 
diff --git a/test/test_config_command.py b/test/test_config_command.py
index 26242132d..35ba6ca0e 100644
--- a/test/test_config_command.py
+++ b/test/test_config_command.py
@@ -7,11 +7,11 @@ import yaml
 from mock import patch
 from tempfile import mkdtemp
 from shutil import rmtree
+import unittest
 
 from beets import ui
 from beets import config
 
-from test._common import unittest
 from test.helper import TestHelper
 from beets.library import Library
 import six
diff --git a/test/test_convert.py b/test/test_convert.py
index 0d1804288..2a32e51e7 100644
--- a/test/test_convert.py
+++ b/test/test_convert.py
@@ -17,8 +17,9 @@ from __future__ import division, absolute_import, print_function
 
 import re
 import os.path
+import unittest
+
 from test import _common
-from test._common import unittest
 from test import helper
 from test.helper import control_stdin, capture_log
 
diff --git a/test/test_datequery.py b/test/test_datequery.py
index c139c0c4a..1e1625db2 100644
--- a/test/test_datequery.py
+++ b/test/test_datequery.py
@@ -18,8 +18,8 @@
 from __future__ import division, absolute_import, print_function
 
 from test import _common
-from test._common import unittest
 from datetime import datetime
+import unittest
 import time
 from beets.dbcore.query import _parse_periods, DateInterval, DateQuery
 
diff --git a/test/test_dbcore.py b/test/test_dbcore.py
index bb6a56fab..d070e257e 100644
--- a/test/test_dbcore.py
+++ b/test/test_dbcore.py
@@ -20,10 +20,10 @@ from __future__ import division, absolute_import, print_function
 import os
 import shutil
 import sqlite3
+import unittest
 from six import assertRaisesRegex
 
 from test import _common
-from test._common import unittest
 from beets import dbcore
 from tempfile import mkstemp
 import six
diff --git a/test/test_discogs.py b/test/test_discogs.py
index 0f89ff923..5fe5926b8 100644
--- a/test/test_discogs.py
+++ b/test/test_discogs.py
@@ -17,8 +17,9 @@
 """
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from test import _common
-from test._common import unittest, Bag
+from test._common import Bag
 
 from beetsplug.discogs import DiscogsPlugin
 
diff --git a/test/test_edit.py b/test/test_edit.py
index a23860b07..2900d092a 100644
--- a/test/test_edit.py
+++ b/test/test_edit.py
@@ -15,10 +15,10 @@
 
 from __future__ import division, absolute_import, print_function
 import codecs
+import unittest
 
 from mock import patch
 from test import _common
-from test._common import unittest
 from test.helper import TestHelper, control_stdin
 from test.test_ui_importer import TerminalImportSessionSetup
 from test.test_importer import ImportHelper, AutotagStub
diff --git a/test/test_embedart.py b/test/test_embedart.py
index 0d64b0d9a..ee08ecb4e 100644
--- a/test/test_embedart.py
+++ b/test/test_embedart.py
@@ -19,9 +19,9 @@ import os.path
 import shutil
 from mock import patch, MagicMock
 import tempfile
+import unittest
 
 from test import _common
-from test._common import unittest
 from test.helper import TestHelper
 
 from beets.mediafile import MediaFile
diff --git a/test/test_embyupdate.py b/test/test_embyupdate.py
index 17e82c73e..2b83a4896 100644
--- a/test/test_embyupdate.py
+++ b/test/test_embyupdate.py
@@ -2,9 +2,9 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
 from test.helper import TestHelper
 from beetsplug import embyupdate
+import unittest
 import responses
 
 
diff --git a/test/test_fetchart.py b/test/test_fetchart.py
index 5def538eb..91bc34101 100644
--- a/test/test_fetchart.py
+++ b/test/test_fetchart.py
@@ -16,7 +16,7 @@
 from __future__ import division, absolute_import, print_function
 
 import os
-from test._common import unittest
+import unittest
 from test.helper import TestHelper
 from beets import util
 
diff --git a/test/test_filefilter.py b/test/test_filefilter.py
index 09b6d94a4..e7a4119d4 100644
--- a/test/test_filefilter.py
+++ b/test/test_filefilter.py
@@ -20,9 +20,9 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import shutil
+import unittest
 
 from test import _common
-from test._common import unittest
 from test.helper import capture_log
 from test.test_importer import ImportHelper
 from beets import config
diff --git a/test/test_files.py b/test/test_files.py
index 884aa40d0..b566f363e 100644
--- a/test/test_files.py
+++ b/test/test_files.py
@@ -21,9 +21,9 @@ import shutil
 import os
 import stat
 from os.path import join
+import unittest
 
 from test import _common
-from test._common import unittest
 from test._common import item, touch
 import beets.library
 from beets import util
diff --git a/test/test_ftintitle.py b/test/test_ftintitle.py
index 711b5daa6..d698263be 100644
--- a/test/test_ftintitle.py
+++ b/test/test_ftintitle.py
@@ -17,7 +17,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from test.helper import TestHelper
 from beetsplug import ftintitle
 
diff --git a/test/test_hidden.py b/test/test_hidden.py
index cb673a64a..e2dd1afb3 100644
--- a/test/test_hidden.py
+++ b/test/test_hidden.py
@@ -17,7 +17,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 import sys
 import tempfile
 from beets.util import hidden
diff --git a/test/test_hook.py b/test/test_hook.py
index cd6b2734f..39fd08959 100644
--- a/test/test_hook.py
+++ b/test/test_hook.py
@@ -17,9 +17,9 @@ from __future__ import division, absolute_import, print_function
 
 import os.path
 import tempfile
+import unittest
 
 from test import _common
-from test._common import unittest
 from test.helper import TestHelper
 
 from beets import config
diff --git a/test/test_ihate.py b/test/test_ihate.py
index 1b23964ae..f52617481 100644
--- a/test/test_ihate.py
+++ b/test/test_ihate.py
@@ -4,7 +4,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from beets import importer
 from beets.library import Item
 from beetsplug.ihate import IHatePlugin
diff --git a/test/test_importadded.py b/test/test_importadded.py
index bd8d8b506..52aa26756 100644
--- a/test/test_importadded.py
+++ b/test/test_importadded.py
@@ -18,8 +18,8 @@ from __future__ import division, absolute_import, print_function
 """Tests for the `importadded` plugin."""
 
 import os
+import unittest
 
-from test._common import unittest
 from test.test_importer import ImportHelper, AutotagStub
 from beets import importer
 from beets import util
diff --git a/test/test_importer.py b/test/test_importer.py
index 55b03378c..500ca027d 100644
--- a/test/test_importer.py
+++ b/test/test_importer.py
@@ -27,9 +27,9 @@ from tempfile import mkstemp
 from zipfile import ZipFile
 from tarfile import TarFile
 from mock import patch, Mock
+import unittest
 
 from test import _common
-from test._common import unittest
 from beets.util import displayable_path, bytestring_path, py3_path
 from test.helper import TestImportSession, TestHelper, has_program, capture_log
 from beets import importer
diff --git a/test/test_importfeeds.py b/test/test_importfeeds.py
index adb2885c7..064f5eee5 100644
--- a/test/test_importfeeds.py
+++ b/test/test_importfeeds.py
@@ -6,8 +6,8 @@ import os
 import os.path
 import tempfile
 import shutil
+import unittest
 
-from test._common import unittest
 from beets import config
 from beets.library import Item, Album, Library
 from beetsplug.importfeeds import ImportFeedsPlugin
diff --git a/test/test_info.py b/test/test_info.py
index f7973796e..f5375e2f6 100644
--- a/test/test_info.py
+++ b/test/test_info.py
@@ -15,7 +15,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from test.helper import TestHelper
 
 from beets.mediafile import MediaFile
diff --git a/test/test_ipfs.py b/test/test_ipfs.py
index 66d895f2e..9c523d6e5 100644
--- a/test/test_ipfs.py
+++ b/test/test_ipfs.py
@@ -20,11 +20,12 @@ from beets import library
 from beets.util import bytestring_path, _fsencoding
 from beetsplug.ipfs import IPFSPlugin
 
-from test import _common
-from test._common import unittest
-from test.helper import TestHelper
+import unittest
 import os
 
+from test import _common
+from test.helper import TestHelper
+
 
 @patch('beets.util.command_output', Mock())
 class IPFSPluginTest(unittest.TestCase, TestHelper):
diff --git a/test/test_keyfinder.py b/test/test_keyfinder.py
index 57e2bcd9c..c2b4227d7 100644
--- a/test/test_keyfinder.py
+++ b/test/test_keyfinder.py
@@ -16,7 +16,7 @@
 from __future__ import division, absolute_import, print_function
 
 from mock import patch
-from test._common import unittest
+import unittest
 from test.helper import TestHelper
 
 from beets.library import Item
diff --git a/test/test_lastgenre.py b/test/test_lastgenre.py
index c060e95a9..f57471f1c 100644
--- a/test/test_lastgenre.py
+++ b/test/test_lastgenre.py
@@ -17,10 +17,10 @@
 
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from mock import Mock
 
 from test import _common
-from test._common import unittest
 from beetsplug import lastgenre
 from beets import config
 
diff --git a/test/test_library.py b/test/test_library.py
index 174e6d527..26c78c99d 100644
--- a/test/test_library.py
+++ b/test/test_library.py
@@ -25,9 +25,9 @@ import re
 import unicodedata
 import sys
 import time
+import unittest
 
 from test import _common
-from test._common import unittest
 from test._common import item
 import beets.library
 import beets.mediafile
diff --git a/test/test_logging.py b/test/test_logging.py
index 6e5e6c8b6..a6b02a572 100644
--- a/test/test_logging.py
+++ b/test/test_logging.py
@@ -7,12 +7,13 @@ import sys
 import threading
 import logging as log
 from six import StringIO
+import unittest
 
 import beets.logging as blog
 from beets import plugins, ui
 import beetsplug
 from test import _common
-from test._common import unittest, TestCase
+from test._common import TestCase
 from test import helper
 import six
 
diff --git a/test/test_lyrics.py b/test/test_lyrics.py
index 429dee4e8..13ba07fdf 100644
--- a/test/test_lyrics.py
+++ b/test/test_lyrics.py
@@ -18,13 +18,13 @@
 from __future__ import division, absolute_import, print_function
 
 import os
-from test import _common
 import sys
 import re
+import unittest
 
+from test import _common
 from mock import MagicMock
 
-from test._common import unittest
 from beetsplug import lyrics
 from beets.library import Item
 from beets.util import confit, bytestring_path
diff --git a/test/test_mb.py b/test/test_mb.py
index 43656451d..ecbcf3c59 100644
--- a/test/test_mb.py
+++ b/test/test_mb.py
@@ -18,9 +18,10 @@
 from __future__ import division, absolute_import, print_function
 
 from test import _common
-from test._common import unittest
 from beets.autotag import mb
 from beets import config
+
+import unittest
 import mock
 
 
diff --git a/test/test_mbsubmit.py b/test/test_mbsubmit.py
index a33d8418b..3402c8464 100644
--- a/test/test_mbsubmit.py
+++ b/test/test_mbsubmit.py
@@ -15,7 +15,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from test.helper import capture_stdout, control_stdin, TestHelper
 from test.test_importer import ImportHelper, AutotagStub
 from test.test_ui_importer import TerminalImportSessionSetup
diff --git a/test/test_mbsync.py b/test/test_mbsync.py
index 57213878c..411af8d0a 100644
--- a/test/test_mbsync.py
+++ b/test/test_mbsync.py
@@ -15,9 +15,9 @@
 
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from mock import patch
 
-from test._common import unittest
 from test.helper import TestHelper,\
     generate_album_info, \
     generate_track_info, \
diff --git a/test/test_mediafile.py b/test/test_mediafile.py
index 32d93f815..463cd534d 100644
--- a/test/test_mediafile.py
+++ b/test/test_mediafile.py
@@ -20,20 +20,14 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import shutil
-import tempfile
 import datetime
 import time
+import unittest
 from six import assertCountEqual
 
 from test import _common
-from test._common import unittest
-from beets.mediafile import MediaFile, MediaField, Image, \
-    MP3DescStorageStyle, StorageStyle, MP4StorageStyle, \
-    ASFStorageStyle, ImageType, CoverArtField, UnreadableFileError
-from beets.library import Item
-from beets.plugins import BeetsPlugin
-from beets.util import bytestring_path
-import six
+from beets.mediafile import MediaFile, Image, \
+    ImageType, CoverArtField, UnreadableFileError
 
 
 class ArtTestMixin(object):
@@ -298,80 +292,8 @@ class GenreListTestMixin(object):
         assertCountEqual(self, mediafile.genres, [u'the genre', u'another'])
 
 
-field_extension = MediaField(
-    MP3DescStorageStyle(u'customtag'),
-    MP4StorageStyle('----:com.apple.iTunes:customtag'),
-    StorageStyle('customtag'),
-    ASFStorageStyle('customtag'),
-)
-
-
-class ExtendedFieldTestMixin(object):
-
-    def test_extended_field_write(self):
-        plugin = BeetsPlugin()
-        plugin.add_media_field('customtag', field_extension)
-
-        try:
-            mediafile = self._mediafile_fixture('empty')
-            mediafile.customtag = u'F#'
-            mediafile.save()
-
-            mediafile = MediaFile(mediafile.path)
-            self.assertEqual(mediafile.customtag, u'F#')
-
-        finally:
-            delattr(MediaFile, 'customtag')
-            Item._media_fields.remove('customtag')
-
-    def test_write_extended_tag_from_item(self):
-        plugin = BeetsPlugin()
-        plugin.add_media_field('customtag', field_extension)
-
-        try:
-            mediafile = self._mediafile_fixture('empty')
-            self.assertIsNone(mediafile.customtag)
-
-            item = Item(path=mediafile.path, customtag=u'Gb')
-            item.write()
-            mediafile = MediaFile(mediafile.path)
-            self.assertEqual(mediafile.customtag, u'Gb')
-
-        finally:
-            delattr(MediaFile, 'customtag')
-            Item._media_fields.remove('customtag')
-
-    def test_read_flexible_attribute_from_file(self):
-        plugin = BeetsPlugin()
-        plugin.add_media_field('customtag', field_extension)
-
-        try:
-            mediafile = self._mediafile_fixture('empty')
-            mediafile.update({'customtag': u'F#'})
-            mediafile.save()
-
-            item = Item.from_path(mediafile.path)
-            self.assertEqual(item['customtag'], u'F#')
-
-        finally:
-            delattr(MediaFile, 'customtag')
-            Item._media_fields.remove('customtag')
-
-    def test_invalid_descriptor(self):
-        with self.assertRaises(ValueError) as cm:
-            MediaFile.add_field('somekey', True)
-        self.assertIn(u'must be an instance of MediaField',
-                      six.text_type(cm.exception))
-
-    def test_overwrite_property(self):
-        with self.assertRaises(ValueError) as cm:
-            MediaFile.add_field('artist', MediaField())
-        self.assertIn(u'property "artist" already exists',
-                      six.text_type(cm.exception))
-
-
 class ReadWriteTestBase(ArtTestMixin, GenreListTestMixin,
-                        ExtendedFieldTestMixin):
+                        _common.TempDirMixin):
     """Test writing and reading tags. Subclasses must set ``extension`` and
     ``audio_properties``.
     """
@@ -456,11 +378,10 @@ class ReadWriteTestBase(ArtTestMixin, GenreListTestMixin,
     ]
 
     def setUp(self):
-        self.temp_dir = bytestring_path(tempfile.mkdtemp())
+        self.create_temp_dir()
 
     def tearDown(self):
-        if os.path.isdir(self.temp_dir):
-            shutil.rmtree(self.temp_dir)
+        self.remove_temp_dir()
 
     def test_read_nonexisting(self):
         mediafile = self._mediafile_fixture('full')
@@ -709,7 +630,9 @@ class ReadWriteTestBase(ArtTestMixin, GenreListTestMixin,
             self.fail('\n  '.join(errors))
 
     def _mediafile_fixture(self, name):
-        name = bytestring_path(name + '.' + self.extension)
+        name = name + '.' + self.extension
+        if not isinstance(name, bytes):
+            name = name.encode('utf8')
         src = os.path.join(_common.RSRC, name)
         target = os.path.join(self.temp_dir, name)
         shutil.copy(src, target)
diff --git a/test/test_mediafile_edge.py b/test/test_mediafile_edge.py
index ae758f142..657ca455d 100644
--- a/test/test_mediafile_edge.py
+++ b/test/test_mediafile_edge.py
@@ -19,18 +19,16 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import shutil
+import unittest
 import mutagen.id3
 
 from test import _common
-from test._common import unittest
-from test.helper import TestHelper
 
-from beets.util import bytestring_path
-import beets.mediafile
+from beets import mediafile
 import six
 
 
-_sc = beets.mediafile._safe_cast
+_sc = mediafile._safe_cast
 
 
 class EdgeTest(unittest.TestCase):
@@ -38,7 +36,7 @@ class EdgeTest(unittest.TestCase):
         # Some files have an ID3 frame that has a list with no elements.
         # This is very hard to produce, so this is just the first 8192
         # bytes of a file found "in the wild".
-        emptylist = beets.mediafile.MediaFile(
+        emptylist = mediafile.MediaFile(
             os.path.join(_common.RSRC, b'emptylist.mp3')
         )
         genre = emptylist.genre
@@ -47,7 +45,7 @@ class EdgeTest(unittest.TestCase):
     def test_release_time_with_space(self):
         # Ensures that release times delimited by spaces are ignored.
         # Amie Street produces such files.
-        space_time = beets.mediafile.MediaFile(
+        space_time = mediafile.MediaFile(
             os.path.join(_common.RSRC, b'space_time.mp3')
         )
         self.assertEqual(space_time.year, 2009)
@@ -57,7 +55,7 @@ class EdgeTest(unittest.TestCase):
     def test_release_time_with_t(self):
         # Ensures that release times delimited by Ts are ignored.
         # The iTunes Store produces such files.
-        t_time = beets.mediafile.MediaFile(
+        t_time = mediafile.MediaFile(
             os.path.join(_common.RSRC, b't_time.m4a')
         )
         self.assertEqual(t_time.year, 1987)
@@ -67,20 +65,20 @@ class EdgeTest(unittest.TestCase):
     def test_tempo_with_bpm(self):
         # Some files have a string like "128 BPM" in the tempo field
         # rather than just a number.
-        f = beets.mediafile.MediaFile(os.path.join(_common.RSRC, b'bpm.mp3'))
+        f = mediafile.MediaFile(os.path.join(_common.RSRC, b'bpm.mp3'))
         self.assertEqual(f.bpm, 128)
 
     def test_discc_alternate_field(self):
         # Different taggers use different vorbis comments to reflect
         # the disc and disc count fields: ensure that the alternative
         # style works.
-        f = beets.mediafile.MediaFile(os.path.join(_common.RSRC, b'discc.ogg'))
+        f = mediafile.MediaFile(os.path.join(_common.RSRC, b'discc.ogg'))
         self.assertEqual(f.disc, 4)
         self.assertEqual(f.disctotal, 5)
 
     def test_old_ape_version_bitrate(self):
         media_file = os.path.join(_common.RSRC, b'oldape.ape')
-        f = beets.mediafile.MediaFile(media_file)
+        f = mediafile.MediaFile(media_file)
         self.assertEqual(f.bitrate, 0)
 
     def test_only_magic_bytes_jpeg(self):
@@ -92,13 +90,13 @@ class EdgeTest(unittest.TestCase):
         with open(magic_bytes_file, 'rb') as f:
             jpg_data = f.read()
         self.assertEqual(
-            beets.mediafile._imghdr_what_wrapper(jpg_data), 'jpeg')
+            mediafile._imghdr_what_wrapper(jpg_data), 'jpeg')
 
     def test_soundcheck_non_ascii(self):
         # Make sure we don't crash when the iTunes SoundCheck field contains
         # non-ASCII binary data.
-        f = beets.mediafile.MediaFile(os.path.join(_common.RSRC,
-                                                   b'soundcheck-nonascii.m4a'))
+        f = mediafile.MediaFile(os.path.join(_common.RSRC,
+                                             b'soundcheck-nonascii.m4a'))
         self.assertEqual(f.rg_track_gain, 0.0)
 
 
@@ -146,7 +144,7 @@ class InvalidValueToleranceTest(unittest.TestCase):
         self.assertEqual(v, 1.0)
 
 
-class SafetyTest(unittest.TestCase, TestHelper):
+class SafetyTest(unittest.TestCase, _common.TempDirMixin):
     def setUp(self):
         self.create_temp_dir()
 
@@ -158,35 +156,35 @@ class SafetyTest(unittest.TestCase, TestHelper):
         with open(fn, 'w') as f:
             f.write(data)
         try:
-            self.assertRaises(exc, beets.mediafile.MediaFile, fn)
+            self.assertRaises(exc, mediafile.MediaFile, fn)
         finally:
             os.unlink(fn)  # delete the temporary file
 
     def test_corrupt_mp3_raises_unreadablefileerror(self):
         # Make sure we catch Mutagen reading errors appropriately.
-        self._exccheck(b'corrupt.mp3', beets.mediafile.UnreadableFileError)
+        self._exccheck(b'corrupt.mp3', mediafile.UnreadableFileError)
 
     def test_corrupt_mp4_raises_unreadablefileerror(self):
-        self._exccheck(b'corrupt.m4a', beets.mediafile.UnreadableFileError)
+        self._exccheck(b'corrupt.m4a', mediafile.UnreadableFileError)
 
     def test_corrupt_flac_raises_unreadablefileerror(self):
-        self._exccheck(b'corrupt.flac', beets.mediafile.UnreadableFileError)
+        self._exccheck(b'corrupt.flac', mediafile.UnreadableFileError)
 
     def test_corrupt_ogg_raises_unreadablefileerror(self):
-        self._exccheck(b'corrupt.ogg', beets.mediafile.UnreadableFileError)
+        self._exccheck(b'corrupt.ogg', mediafile.UnreadableFileError)
 
     def test_invalid_ogg_header_raises_unreadablefileerror(self):
-        self._exccheck(b'corrupt.ogg', beets.mediafile.UnreadableFileError,
+        self._exccheck(b'corrupt.ogg', mediafile.UnreadableFileError,
                        'OggS\x01vorbis')
 
     def test_corrupt_monkeys_raises_unreadablefileerror(self):
-        self._exccheck(b'corrupt.ape', beets.mediafile.UnreadableFileError)
+        self._exccheck(b'corrupt.ape', mediafile.UnreadableFileError)
 
     def test_invalid_extension_raises_filetypeerror(self):
-        self._exccheck(b'something.unknown', beets.mediafile.FileTypeError)
+        self._exccheck(b'something.unknown', mediafile.FileTypeError)
 
     def test_magic_xml_raises_unreadablefileerror(self):
-        self._exccheck(b'nothing.xml', beets.mediafile.UnreadableFileError,
+        self._exccheck(b'nothing.xml', mediafile.UnreadableFileError,
                        "ftyp")
 
     @unittest.skipUnless(_common.HAVE_SYMLINK, u'platform lacks symlink')
@@ -194,8 +192,8 @@ class SafetyTest(unittest.TestCase, TestHelper):
         fn = os.path.join(_common.RSRC, b'brokenlink')
         os.symlink('does_not_exist', fn)
         try:
-            self.assertRaises(beets.mediafile.UnreadableFileError,
-                              beets.mediafile.MediaFile, fn)
+            self.assertRaises(mediafile.UnreadableFileError,
+                              mediafile.MediaFile, fn)
         finally:
             os.unlink(fn)
 
@@ -206,19 +204,19 @@ class SideEffectsTest(unittest.TestCase):
 
     def test_opening_tagless_file_leaves_untouched(self):
         old_mtime = os.stat(self.empty).st_mtime
-        beets.mediafile.MediaFile(self.empty)
+        mediafile.MediaFile(self.empty)
         new_mtime = os.stat(self.empty).st_mtime
         self.assertEqual(old_mtime, new_mtime)
 
 
-class MP4EncodingTest(unittest.TestCase, TestHelper):
+class MP4EncodingTest(unittest.TestCase, _common.TempDirMixin):
     def setUp(self):
         self.create_temp_dir()
         src = os.path.join(_common.RSRC, b'full.m4a')
         self.path = os.path.join(self.temp_dir, b'test.m4a')
         shutil.copy(src, self.path)
 
-        self.mf = beets.mediafile.MediaFile(self.path)
+        self.mf = mediafile.MediaFile(self.path)
 
     def tearDown(self):
         self.remove_temp_dir()
@@ -226,18 +224,18 @@ class MP4EncodingTest(unittest.TestCase, TestHelper):
     def test_unicode_label_in_m4a(self):
         self.mf.label = u'foo\xe8bar'
         self.mf.save()
-        new_mf = beets.mediafile.MediaFile(self.path)
+        new_mf = mediafile.MediaFile(self.path)
         self.assertEqual(new_mf.label, u'foo\xe8bar')
 
 
-class MP3EncodingTest(unittest.TestCase, TestHelper):
+class MP3EncodingTest(unittest.TestCase, _common.TempDirMixin):
     def setUp(self):
         self.create_temp_dir()
         src = os.path.join(_common.RSRC, b'full.mp3')
         self.path = os.path.join(self.temp_dir, b'test.mp3')
         shutil.copy(src, self.path)
 
-        self.mf = beets.mediafile.MediaFile(self.path)
+        self.mf = mediafile.MediaFile(self.path)
 
     def test_comment_with_latin1_encoding(self):
         # Set up the test file with a Latin1-encoded COMM frame. The encoding
@@ -250,7 +248,7 @@ class MP3EncodingTest(unittest.TestCase, TestHelper):
         self.mf.save()
 
 
-class ZeroLengthMediaFile(beets.mediafile.MediaFile):
+class ZeroLengthMediaFile(mediafile.MediaFile):
     @property
     def length(self):
         return 0.0
@@ -271,7 +269,7 @@ class TypeTest(unittest.TestCase):
     def setUp(self):
         super(TypeTest, self).setUp()
         path = os.path.join(_common.RSRC, b'full.mp3')
-        self.mf = beets.mediafile.MediaFile(path)
+        self.mf = mediafile.MediaFile(path)
 
     def test_year_integer_in_string(self):
         self.mf.year = u'2009'
@@ -303,45 +301,45 @@ class TypeTest(unittest.TestCase):
 
 class SoundCheckTest(unittest.TestCase):
     def test_round_trip(self):
-        data = beets.mediafile._sc_encode(1.0, 1.0)
-        gain, peak = beets.mediafile._sc_decode(data)
+        data = mediafile._sc_encode(1.0, 1.0)
+        gain, peak = mediafile._sc_decode(data)
         self.assertEqual(gain, 1.0)
         self.assertEqual(peak, 1.0)
 
     def test_decode_zero(self):
         data = b' 80000000 80000000 00000000 00000000 00000000 00000000 ' \
                b'00000000 00000000 00000000 00000000'
-        gain, peak = beets.mediafile._sc_decode(data)
+        gain, peak = mediafile._sc_decode(data)
         self.assertEqual(gain, 0.0)
         self.assertEqual(peak, 0.0)
 
     def test_malformatted(self):
-        gain, peak = beets.mediafile._sc_decode(b'foo')
+        gain, peak = mediafile._sc_decode(b'foo')
         self.assertEqual(gain, 0.0)
         self.assertEqual(peak, 0.0)
 
     def test_special_characters(self):
-        gain, peak = beets.mediafile._sc_decode(u'caf\xe9'.encode('utf-8'))
+        gain, peak = mediafile._sc_decode(u'caf\xe9'.encode('utf-8'))
         self.assertEqual(gain, 0.0)
         self.assertEqual(peak, 0.0)
 
     def test_decode_handles_unicode(self):
         # Most of the time, we expect to decode the raw bytes. But some formats
         # might give us text strings, which we need to handle.
-        gain, peak = beets.mediafile._sc_decode(u'caf\xe9')
+        gain, peak = mediafile._sc_decode(u'caf\xe9')
         self.assertEqual(gain, 0.0)
         self.assertEqual(peak, 0.0)
 
 
-class ID3v23Test(unittest.TestCase, TestHelper):
-    def _make_test(self, ext='mp3', id3v23=False):
+class ID3v23Test(unittest.TestCase, _common.TempDirMixin):
+    def _make_test(self, ext=b'mp3', id3v23=False):
         self.create_temp_dir()
         src = os.path.join(_common.RSRC,
-                           bytestring_path('full.{0}'.format(ext)))
+                           b'full.' + ext)
         self.path = os.path.join(self.temp_dir,
-                                 bytestring_path('test.{0}'.format(ext)))
+                                 b'test.' + ext)
         shutil.copy(src, self.path)
-        return beets.mediafile.MediaFile(self.path, id3v23=id3v23)
+        return mediafile.MediaFile(self.path, id3v23=id3v23)
 
     def _delete_test(self):
         self.remove_temp_dir()
@@ -369,7 +367,7 @@ class ID3v23Test(unittest.TestCase, TestHelper):
             self._delete_test()
 
     def test_v23_on_non_mp3_is_noop(self):
-        mf = self._make_test('m4a', id3v23=True)
+        mf = self._make_test(b'm4a', id3v23=True)
         try:
             mf.year = 2013
             mf.save()
@@ -386,9 +384,9 @@ class ID3v23Test(unittest.TestCase, TestHelper):
             mf = self._make_test(id3v23=v23)
             try:
                 mf.images = [
-                    beets.mediafile.Image(b'data', desc=u""),
-                    beets.mediafile.Image(b'data', desc=u"foo"),
-                    beets.mediafile.Image(b'data', desc=u"\u0185"),
+                    mediafile.Image(b'data', desc=u""),
+                    mediafile.Image(b'data', desc=u"foo"),
+                    mediafile.Image(b'data', desc=u"\u0185"),
                 ]
                 mf.save()
                 apic_frames = mf.mgfile.tags.getall('APIC')
diff --git a/test/test_metasync.py b/test/test_metasync.py
index 60f63c413..ef16c57a2 100644
--- a/test/test_metasync.py
+++ b/test/test_metasync.py
@@ -21,9 +21,9 @@ import time
 from datetime import datetime
 from beets.library import Item
 from beets.util import py3_path
+import unittest
 
 from test import _common
-from test._common import unittest
 from test.helper import TestHelper
 
 
diff --git a/test/test_mpdstats.py b/test/test_mpdstats.py
index febf292d8..7452be86b 100644
--- a/test/test_mpdstats.py
+++ b/test/test_mpdstats.py
@@ -15,8 +15,8 @@
 
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from mock import Mock, patch, call, ANY
-from test._common import unittest
 from test.helper import TestHelper
 
 from beets.library import Item
diff --git a/test/test_permissions.py b/test/test_permissions.py
index 040839110..ed84798f1 100644
--- a/test/test_permissions.py
+++ b/test/test_permissions.py
@@ -6,9 +6,9 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import platform
+import unittest
 from mock import patch, Mock
 
-from test._common import unittest
 from test.helper import TestHelper
 from beets.util import displayable_path
 from beetsplug.permissions import (check_permissions,
diff --git a/test/test_pipeline.py b/test/test_pipeline.py
index 4d3bde4d0..228deb50e 100644
--- a/test/test_pipeline.py
+++ b/test/test_pipeline.py
@@ -18,8 +18,8 @@
 from __future__ import division, absolute_import, print_function
 
 import six
+import unittest
 
-from test._common import unittest
 from beets.util import pipeline
 
 
diff --git a/test/test_play.py b/test/test_play.py
index c05e24c51..9d66d7466 100644
--- a/test/test_play.py
+++ b/test/test_play.py
@@ -19,9 +19,9 @@ from __future__ import division, absolute_import, print_function
 
 import os
 
+import unittest
 from mock import patch, ANY
 
-from test._common import unittest
 from test.helper import TestHelper, control_stdin
 
 from beets.ui import UserError
diff --git a/test/test_player.py b/test/test_player.py
index c8fec446b..0a576f0ba 100644
--- a/test/test_player.py
+++ b/test/test_player.py
@@ -17,7 +17,7 @@
 """
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from beetsplug import bpd
 
 
diff --git a/test/test_plexupdate.py b/test/test_plexupdate.py
index 2a2b1cbaf..f8b0bdcd9 100644
--- a/test/test_plexupdate.py
+++ b/test/test_plexupdate.py
@@ -2,9 +2,9 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
 from test.helper import TestHelper
 from beetsplug.plexupdate import get_music_section, update_plex
+import unittest
 import responses
 
 
diff --git a/test/test_plugin_mediafield.py b/test/test_plugin_mediafield.py
new file mode 100644
index 000000000..d9d2b0a1f
--- /dev/null
+++ b/test/test_plugin_mediafield.py
@@ -0,0 +1,107 @@
+# -*- coding: utf-8 -*-
+# This file is part of beets.
+# Copyright 2016, 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.
+
+"""Tests the facility that lets plugins add custom field to MediaFile.
+"""
+from __future__ import division, absolute_import, print_function
+
+import os
+import six
+import shutil
+
+from test import _common
+from beets.library import Item
+from beets import mediafile
+from beets.plugins import BeetsPlugin
+from beets.util import bytestring_path
+
+
+field_extension = mediafile.MediaField(
+    mediafile.MP3DescStorageStyle(u'customtag'),
+    mediafile.MP4StorageStyle('----:com.apple.iTunes:customtag'),
+    mediafile.StorageStyle('customtag'),
+    mediafile.ASFStorageStyle('customtag'),
+)
+
+
+class ExtendedFieldTestMixin(_common.TestCase):
+
+    def _mediafile_fixture(self, name, extension='mp3'):
+        name = bytestring_path(name + '.' + extension)
+        src = os.path.join(_common.RSRC, name)
+        target = os.path.join(self.temp_dir, name)
+        shutil.copy(src, target)
+        return mediafile.MediaFile(target)
+
+    def test_extended_field_write(self):
+        plugin = BeetsPlugin()
+        plugin.add_media_field('customtag', field_extension)
+
+        try:
+            mf = self._mediafile_fixture('empty')
+            mf.customtag = u'F#'
+            mf.save()
+
+            mf = mediafile.MediaFile(mf.path)
+            self.assertEqual(mf.customtag, u'F#')
+
+        finally:
+            delattr(mediafile.MediaFile, 'customtag')
+            Item._media_fields.remove('customtag')
+
+    def test_write_extended_tag_from_item(self):
+        plugin = BeetsPlugin()
+        plugin.add_media_field('customtag', field_extension)
+
+        try:
+            mf = self._mediafile_fixture('empty')
+            self.assertIsNone(mf.customtag)
+
+            item = Item(path=mf.path, customtag=u'Gb')
+            item.write()
+            mf = mediafile.MediaFile(mf.path)
+            self.assertEqual(mf.customtag, u'Gb')
+
+        finally:
+            delattr(mediafile.MediaFile, 'customtag')
+            Item._media_fields.remove('customtag')
+
+    def test_read_flexible_attribute_from_file(self):
+        plugin = BeetsPlugin()
+        plugin.add_media_field('customtag', field_extension)
+
+        try:
+            mf = self._mediafile_fixture('empty')
+            mf.update({'customtag': u'F#'})
+            mf.save()
+
+            item = Item.from_path(mf.path)
+            self.assertEqual(item['customtag'], u'F#')
+
+        finally:
+            delattr(mediafile.MediaFile, 'customtag')
+            Item._media_fields.remove('customtag')
+
+    def test_invalid_descriptor(self):
+        with self.assertRaises(ValueError) as cm:
+            mediafile.MediaFile.add_field('somekey', True)
+        self.assertIn(u'must be an instance of MediaField',
+                      six.text_type(cm.exception))
+
+    def test_overwrite_property(self):
+        with self.assertRaises(ValueError) as cm:
+            mediafile.MediaFile.add_field('artist', mediafile.MediaField())
+        self.assertIn(u'property "artist" already exists',
+                      six.text_type(cm.exception))
diff --git a/test/test_plugins.py b/test/test_plugins.py
index d45e317ca..c4a5792ff 100644
--- a/test/test_plugins.py
+++ b/test/test_plugins.py
@@ -19,6 +19,7 @@ import os
 from mock import patch, Mock, ANY
 import shutil
 import itertools
+import unittest
 
 from beets.importer import SingletonImportTask, SentinelImportTask, \
     ArchiveImportTask, action
@@ -30,7 +31,7 @@ from beets.util import displayable_path, bytestring_path
 
 from test.test_importer import ImportHelper, AutotagStub
 from test.test_ui_importer import TerminalImportSessionSetup
-from test._common import unittest, RSRC
+from test._common import RSRC
 from test import helper
 
 
diff --git a/test/test_query.py b/test/test_query.py
index e0bbebfe1..41672ab35 100644
--- a/test/test_query.py
+++ b/test/test_query.py
@@ -21,9 +21,9 @@ from functools import partial
 from mock import patch
 import os
 import sys
+import unittest
 
 from test import _common
-from test._common import unittest
 from test import helper
 
 import beets.library
diff --git a/test/test_replaygain.py b/test/test_replaygain.py
index d2a8aa9ba..6ea21ecb6 100644
--- a/test/test_replaygain.py
+++ b/test/test_replaygain.py
@@ -16,14 +16,15 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
+import six
+
 from test.helper import TestHelper, has_program
 
 from beets import config
 from beets.mediafile import MediaFile
 from beetsplug.replaygain import (FatalGstreamerPluginReplayGainError,
                                   GStreamerBackend)
-import six
 
 try:
     import gi
diff --git a/test/test_smartplaylist.py b/test/test_smartplaylist.py
index 5e1fed084..af60501a4 100644
--- a/test/test_smartplaylist.py
+++ b/test/test_smartplaylist.py
@@ -18,6 +18,7 @@ from __future__ import division, absolute_import, print_function
 from os import path, remove
 from tempfile import mkdtemp
 from shutil import rmtree
+import unittest
 
 from mock import Mock, MagicMock
 
@@ -29,7 +30,6 @@ from beets.util import syspath, bytestring_path, py3_path, CHAR_REPLACE
 from beets.ui import UserError
 from beets import config
 
-from test._common import unittest
 from test.helper import TestHelper
 
 
diff --git a/test/test_sort.py b/test/test_sort.py
index d10bd5759..d611ff2d6 100644
--- a/test/test_sort.py
+++ b/test/test_sort.py
@@ -17,8 +17,8 @@
 """
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from test import _common
-from test._common import unittest
 import beets.library
 from beets import dbcore
 from beets import config
diff --git a/test/test_spotify.py b/test/test_spotify.py
index 20101d76c..17f3ef42f 100644
--- a/test/test_spotify.py
+++ b/test/test_spotify.py
@@ -6,9 +6,9 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import responses
+import unittest
 
 from test import _common
-from test._common import unittest
 from beets import config
 from beets.library import Item
 from beetsplug import spotify
diff --git a/test/test_template.py b/test/test_template.py
index 67d5d97fe..1cbe9be0c 100644
--- a/test/test_template.py
+++ b/test/test_template.py
@@ -17,9 +17,9 @@
 """
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
-from beets.util import functemplate
+import unittest
 import six
+from beets.util import functemplate
 
 
 def _normexpr(expr):
diff --git a/test/test_the.py b/test/test_the.py
index 422723386..72e9bf161 100644
--- a/test/test_the.py
+++ b/test/test_the.py
@@ -4,7 +4,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from test import _common
 from beets import config
 from beetsplug.the import ThePlugin, PATTERN_A, PATTERN_THE, FORMAT
diff --git a/test/test_thumbnails.py b/test/test_thumbnails.py
index fe1c80f4a..d287c073a 100644
--- a/test/test_thumbnails.py
+++ b/test/test_thumbnails.py
@@ -19,8 +19,8 @@ import os.path
 from mock import Mock, patch, call
 from tempfile import mkdtemp
 from shutil import rmtree
+import unittest
 
-from test._common import unittest
 from test.helper import TestHelper
 
 from beets.util import bytestring_path
diff --git a/test/test_types_plugin.py b/test/test_types_plugin.py
index 826dd5ea7..541bd30df 100644
--- a/test/test_types_plugin.py
+++ b/test/test_types_plugin.py
@@ -17,8 +17,8 @@ from __future__ import division, absolute_import, print_function
 
 import time
 from datetime import datetime
+import unittest
 
-from test._common import unittest
 from test.helper import TestHelper
 
 from beets.util.confit import ConfigValueError
diff --git a/test/test_ui.py b/test/test_ui.py
index 99459603a..681900ae4 100644
--- a/test/test_ui.py
+++ b/test/test_ui.py
@@ -24,10 +24,10 @@ import subprocess
 import platform
 from copy import deepcopy
 import six
+import unittest
 
 from mock import patch, Mock
 from test import _common
-from test._common import unittest
 from test.helper import capture_stdout, has_program, TestHelper, control_stdin
 
 from beets import library
diff --git a/test/test_ui_commands.py b/test/test_ui_commands.py
index 5cd1131eb..764d1b009 100644
--- a/test/test_ui_commands.py
+++ b/test/test_ui_commands.py
@@ -20,9 +20,9 @@ from __future__ import division, absolute_import, print_function
 
 import os
 import shutil
+import unittest
 
 from test import _common
-from test._common import unittest
 
 from beets import library
 from beets import ui
diff --git a/test/test_ui_importer.py b/test/test_ui_importer.py
index cc2938ad3..48a66dc5f 100644
--- a/test/test_ui_importer.py
+++ b/test/test_ui_importer.py
@@ -20,8 +20,9 @@ test_importer module. But here the test importer inherits from
 """
 
 from __future__ import division, absolute_import, print_function
+import unittest
 
-from test._common import unittest, DummyIO
+from test._common import DummyIO
 from test import test_importer
 from beets.ui.commands import TerminalImportSession
 from beets import importer
diff --git a/test/test_ui_init.py b/test/test_ui_init.py
index 0628d3879..3a146b0c0 100644
--- a/test/test_ui_init.py
+++ b/test/test_ui_init.py
@@ -18,8 +18,8 @@
 
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from test import _common
-from test._common import unittest
 
 from beets import ui
 
diff --git a/test/test_util.py b/test/test_util.py
index 96d02f955..0d0bbd7b0 100644
--- a/test/test_util.py
+++ b/test/test_util.py
@@ -20,10 +20,10 @@ import sys
 import re
 import os
 import subprocess
+import unittest
 
 from mock import patch, Mock
 
-from test._common import unittest
 from test import _common
 from beets import util
 import six
diff --git a/test/test_vfs.py b/test/test_vfs.py
index 0b25a1031..b94acfd09 100644
--- a/test/test_vfs.py
+++ b/test/test_vfs.py
@@ -16,8 +16,8 @@
 """Tests for the virtual filesystem builder.."""
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from test import _common
-from test._common import unittest
 from beets import library
 from beets import vfs
 
diff --git a/test/test_web.py b/test/test_web.py
index 7d477227c..e72ecf33d 100644
--- a/test/test_web.py
+++ b/test/test_web.py
@@ -4,9 +4,9 @@
 
 from __future__ import division, absolute_import, print_function
 
+import unittest
 from six import assertCountEqual
 
-from test._common import unittest
 from test import _common
 import json
 from beets.library import Item, Album
diff --git a/test/test_zero.py b/test/test_zero.py
index 7b90e22b3..5842d9ed4 100644
--- a/test/test_zero.py
+++ b/test/test_zero.py
@@ -4,7 +4,7 @@
 
 from __future__ import division, absolute_import, print_function
 
-from test._common import unittest
+import unittest
 from test.helper import TestHelper
 
 from beets.library import Item
diff --git a/test/testall.py b/test/testall.py
index aebda21ee..88eb70117 100755
--- a/test/testall.py
+++ b/test/testall.py
@@ -20,8 +20,7 @@ from __future__ import division, absolute_import, print_function
 import os
 import re
 import sys
-
-from test._common import unittest
+import unittest
 
 pkgpath = os.path.dirname(__file__) or '.'
 sys.path.append(pkgpath)
diff --git a/tox.ini b/tox.ini
index 28fd3636e..8115395c6 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py27-test, py27-flake8, docs
+envlist = py27-test, py35-test, py27-flake8, docs
 
 # The exhaustive list of environments is:
 # envlist = py{27,34,35}-{test,cov}, py{27,34,35}-flake8, docs