Drop Python 2 support

.travis.yml

@@ -18,8 +18,6 @@ env:
 matrix:
   fast_finish: true
   include:
-    - { python: "2.7", env: DJANGO="==1.11.*" }
-
     - { python: "3.7", env: DJANGO="==2.0.*", sudo: true }
     - { python: "3.7", env: DJANGO="==2.1.*", sudo: true }
     - { python: "3.7", env: DJANGO="==2.2.*", sudo: true }
@@ -32,7 +30,7 @@ services:
   - mysql
 install:
   # mysqlclient 1.4 is not compatible with Django 1.11
-  - pip install flake8 coverage mock sphinx django$DJANGO psycopg2 mysqlclient==1.3.14 -e .
+  - pip install flake8 coverage sphinx django$DJANGO psycopg2 mysqlclient==1.3.14 -e .
 before_script:
   - mysql -e 'create database test_project'
   - psql -c 'create database test_project;' -U postgres;

README.rst

@@ -11,7 +11,7 @@ version control for model instances.
 Requirements
 ============
 
-- Python 2.7 or later
+- Python 3.5 or later
 - Django 1.11 or later
 
 Features

docs/admin.rst

@@ -100,7 +100,7 @@ A subclass of ``django.contrib.ModelAdmin`` providing rollback and recovery.
 
         def reversion_register(self, model, **options):
             options["exclude"] = ("some_field",)
-            super(YourModelAdmin, self).reversion_register(model, **options)
+            super().reversion_register(model, **options)
 
     ``model``
         The model that will be registered with django-reversion.

reversion/admin.py

@@ -1,4 +1,3 @@
-from __future__ import unicode_literals
 import json
 from contextlib import contextmanager
 from django.db import models, transaction, connection
@@ -74,15 +73,15 @@ def log_addition(self, request, object, change_message=None):
                 set_comment(json.dumps(change_message))
             else:
                 set_comment(change_message)
-        super(VersionAdmin, self).log_addition(request, object, change_message)
+        super().log_addition(request, object, change_message)
 
     def log_change(self, request, object, message):
         if is_active():
             if isinstance(message, list):
                 set_comment(json.dumps(message))
             else:
                 set_comment(message)
-        super(VersionAdmin, self).log_change(request, object, message)
+        super().log_change(request, object, message)
 
     # Auto-registration.
 
@@ -128,7 +127,7 @@ def _reversion_introspect_inline_admin(self, inline):
         return inline_model, follow_field
 
     def __init__(self, *args, **kwargs):
-        super(VersionAdmin, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         # Automatically register models if required.
         if not is_registered(self.model):
             inline_fields = ()
@@ -141,7 +140,7 @@ def __init__(self, *args, **kwargs):
             self._reversion_autoregister(self.model, inline_fields)
 
     def get_urls(self):
-        urls = super(VersionAdmin, self).get_urls()
+        urls = super().get_urls()
         admin_site = self.admin_site
         opts = self.model._meta
         info = opts.app_label, opts.model_name,
@@ -156,11 +155,11 @@ def get_urls(self):
 
     def add_view(self, request, form_url='', extra_context=None):
         with self.create_revision(request):
-            return super(VersionAdmin, self).add_view(request, form_url, extra_context)
+            return super().add_view(request, form_url, extra_context)
 
     def change_view(self, request, object_id, form_url='', extra_context=None):
         with self.create_revision(request):
-            return super(VersionAdmin, self).change_view(request, object_id, form_url, extra_context)
+            return super().change_view(request, object_id, form_url, extra_context)
 
     def _reversion_revisionform_view(self, request, version, template_name, extra_context=None):
         # Check that database transactions are supported.
@@ -233,7 +232,7 @@ def changelist_view(self, request, extra_context=None):
                 "has_change_permission": self.has_change_permission(request),
             }
             context.update(extra_context or {})
-            return super(VersionAdmin, self).changelist_view(request, context)
+            return super().changelist_view(request, context)
 
     def recoverlist_view(self, request, extra_context=None):
         """Displays a deleted model to allow recovery."""
@@ -289,4 +288,4 @@ def history_view(self, request, object_id, extra_context=None):
         # Compile the context.
         context = {"action_list": action_list}
         context.update(extra_context or {})
-        return super(VersionAdmin, self).history_view(request, object_id, context)
+        return super().history_view(request, object_id, context)

reversion/management/commands/__init__.py

@@ -1,4 +1,3 @@
-from __future__ import unicode_literals
 from django.apps import apps
 from django.conf import settings
 from django.contrib import admin
@@ -9,7 +8,7 @@
 class BaseRevisionCommand(BaseCommand):
 
     def add_arguments(self, parser):
-        super(BaseRevisionCommand, self).add_arguments(parser)
+        super().add_arguments(parser)
         parser.add_argument(
             "app_label",
             metavar="app_label",

reversion/management/commands/createinitialrevisions.py

@@ -1,5 +1,3 @@
-from __future__ import unicode_literals
-
 import json
 
 from django.apps import apps
@@ -15,7 +13,7 @@ class Command(BaseRevisionCommand):
     help = "Creates initial revisions for a given app [and model]."
 
     def add_arguments(self, parser):
-        super(Command, self).add_arguments(parser)
+        super().add_arguments(parser)
         parser.add_argument(
             "--comment",
             action="store",

reversion/management/commands/deleterevisions.py

@@ -1,4 +1,3 @@
-from __future__ import unicode_literals
 from datetime import timedelta
 from django.db import transaction, models, router
 from django.utils import timezone
@@ -11,7 +10,7 @@ class Command(BaseRevisionCommand):
     help = "Deletes revisions for a given app [and model]."
 
     def add_arguments(self, parser):
-        super(Command, self).add_arguments(parser)
+        super().add_arguments(parser)
         parser.add_argument(
             "--days",
             default=0,

reversion/middleware.py

@@ -14,7 +14,7 @@ class RevisionMiddleware(object):
     atomic = True
 
     def __init__(self, get_response=None):
-        super(RevisionMiddleware, self).__init__()
+        super().__init__()
         # Support Django 1.10 middleware.
         if get_response is not None:
             self.get_response = create_revision(

reversion/migrations/0001_squashed_0004_auto_20160611_1202.py

@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.7 on 2016-06-06 13:22
-from __future__ import unicode_literals
-
 from django.conf import settings
 from django.db import migrations, models
 import django.db.models.deletion

reversion/models.py

@@ -1,5 +1,3 @@
-from __future__ import unicode_literals
-
 from collections import defaultdict
 from itertools import chain, groupby
 
@@ -13,7 +11,7 @@
 from django.db import IntegrityError, connections, models, router, transaction
 from django.db.models.deletion import Collector
 from django.db.models.functions import Cast
-from django.utils.encoding import force_text, python_2_unicode_compatible
+from django.utils.encoding import force_text
 from django.utils.functional import cached_property
 from django.utils.translation import ugettext
 from django.utils.translation import ugettext_lazy as _
@@ -39,7 +37,6 @@ def _safe_revert(versions):
         _safe_revert(unreverted_versions)
 
 
-@python_2_unicode_compatible
 class Revision(models.Model):
 
     """A group of related serialized versions."""
@@ -171,7 +168,6 @@ def get_unique(self):
             last_key = key
 
 
-@python_2_unicode_compatible
 class Version(models.Model):
 
     """A saved version of a database model."""
@@ -309,11 +305,11 @@ class _Str(models.Func):
     template = "%(function)s(%(expressions)s as %(db_type)s)"
 
     def __init__(self, expression):
-        super(_Str, self).__init__(expression, output_field=models.TextField())
+        super().__init__(expression, output_field=models.TextField())
 
     def as_sql(self, compiler, connection):
         self.extra["db_type"] = self.output_field.db_type(connection)
-        return super(_Str, self).as_sql(compiler, connection)
+        return super().as_sql(compiler, connection)
 
 
 def _safe_subquery(method, left_query, left_field_name, right_subquery, right_field_name):

reversion/revisions.py

@@ -1,4 +1,3 @@
-from __future__ import unicode_literals
 from collections import namedtuple, defaultdict
 from contextlib import contextmanager
 from functools import wraps
@@ -10,7 +9,7 @@
 from django.db.models.query import QuerySet
 from django.db.models.signals import post_save, m2m_changed
 from django.utils.encoding import force_text
-from django.utils import timezone, six
+from django.utils import timezone
 from reversion.errors import RevisionManagementError, RegistrationError
 from reversion.signals import pre_revision_commit, post_revision_commit
 
@@ -355,7 +354,7 @@ def _get_senders_and_signals(model):
     opts = model._meta.concrete_model._meta
     for field in opts.local_many_to_many:
         m2m_model = field.remote_field.through
-        if isinstance(m2m_model, six.string_types):
+        if isinstance(m2m_model, str):
             if "." not in m2m_model:
                 m2m_model = "{app_label}.{m2m_model}".format(
                     app_label=opts.app_label,

reversion/views.py

@@ -61,7 +61,7 @@ class RevisionMixin(object):
     revision_atomic = True
 
     def __init__(self, *args, **kwargs):
-        super(RevisionMixin, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self.dispatch = create_revision(
             manage_manually=self.revision_manage_manually,
             using=self.revision_using,

setup.py

@@ -37,7 +37,6 @@
         "License :: OSI Approved :: BSD License",
         "Operating System :: OS Independent",
         "Programming Language :: Python",
-        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',

tests/manage.py

@@ -6,17 +6,10 @@
     os.environ.setdefault("DJANGO_SETTINGS_MODULE", "test_project.settings")
     try:
         from django.core.management import execute_from_command_line
-    except ImportError:
-        # The above import may fail for some other reason. Ensure that the
-        # issue is really that Django is missing to avoid masking other
-        # exceptions on Python 2.
-        try:
-            import django  # noqa
-        except ImportError:
-            raise ImportError(
-                "Couldn't import Django. Are you sure it's installed and "
-                "available on your PYTHONPATH environment variable? Did you "
-                "forget to activate a virtual environment?"
-            )
-        raise
+    except ImportError as exc:
+        raise ImportError(
+            "Couldn't import Django. Are you sure it's installed and "
+            "available on your PYTHONPATH environment variable? Did you "
+            "forget to activate a virtual environment?"
+        ) from exc
     execute_from_command_line(sys.argv)

tests/test_app/migrations/0001_initial.py

@@ -1,7 +1,4 @@
-# -*- coding: utf-8 -*-
 # Generated by Django 1.9.7 on 2016-06-14 10:27
-from __future__ import unicode_literals
-
 from django.db import migrations, models
 import django.db.models.deletion
 

tests/test_app/tests/base.py

@@ -1,20 +1,18 @@
 from datetime import timedelta
+from importlib import import_module, reload
+from io import StringIO
+
 from django.conf import settings
 from django.contrib.auth.models import User
 from django.core.management import call_command
 from django.urls import clear_url_caches
 from django.test import TestCase, TransactionTestCase
 from django.test.utils import override_settings
 from django.utils import timezone
-from django.utils.six import StringIO, assertRegex
+
 import reversion
 from reversion.models import Revision, Version
 from test_app.models import TestModel, TestModelParent
-from importlib import import_module
-try:
-    from importlib import reload
-except ImportError:  # Python 2.7
-    pass
 
 
 # Test helpers.
@@ -28,12 +26,12 @@ def reloadUrls(self):
         clear_url_caches()
 
     def setUp(self):
-        super(TestBaseMixin, self).setUp()
+        super().setUp()
         for model in list(reversion.get_registered_models()):
             reversion.unregister(model)
 
     def tearDown(self):
-        super(TestBaseMixin, self).tearDown()
+        super().tearDown()
         for model in list(reversion.get_registered_models()):
             reversion.unregister(model)
 
@@ -48,7 +46,7 @@ def assertSingleRevision(self, objects, user=None, comment="", meta_names=(), da
         revision = Version.objects.using(using).get_for_object(objects[0], model_db=model_db).get().revision
         self.assertEqual(revision.user, user)
         if hasattr(comment, 'pattern'):
-            assertRegex(self, revision.get_comment(), comment)
+            self.assertRegex(revision.get_comment(), comment)
         elif comment is not None:  # Allow a wildcard comment.
             self.assertEqual(revision.get_comment(), comment)
         self.assertAlmostEqual(revision.date_created, date_created or timezone.now(), delta=timedelta(seconds=1))
@@ -81,22 +79,22 @@ class TestBaseTransaction(TestBaseMixin, TransactionTestCase):
 class TestModelMixin(object):
 
     def setUp(self):
-        super(TestModelMixin, self).setUp()
+        super().setUp()
         reversion.register(TestModel)
 
 
 class TestModelParentMixin(TestModelMixin):
 
     def setUp(self):
-        super(TestModelParentMixin, self).setUp()
+        super().setUp()
         reversion.register(TestModelParent, follow=("testmodel_ptr",))
 
 
 @override_settings(PASSWORD_HASHERS=["django.contrib.auth.hashers.MD5PasswordHasher"])
 class UserMixin(TestBase):
 
     def setUp(self):
-        super(UserMixin, self).setUp()
+        super().setUp()
         self.user = User(username="test", is_staff=True, is_superuser=True)
         self.user.set_password("password")
         self.user.save()
@@ -105,5 +103,5 @@ def setUp(self):
 class LoginMixin(UserMixin):
 
     def setUp(self):
-        super(LoginMixin, self).setUp()
+        super().setUp()
         self.client.login(username="test", password="password")