Drop Python 2 support. (#394)

.travis.yml

@@ -3,7 +3,6 @@ dist: xenial
 language: python
 cache: pip
 python:
-- 2.7
 - 3.7
 - 3.6
 install: pip install tox-travis codecov

CHANGES.rst

@@ -5,6 +5,7 @@ CHANGES
 ------------------
 
 - Remove hacks for previously supported Django versions. (Fixes GH-390)
+- Dropped support for Python 2.7. (Fixes GH-393)
 
 3.3.0 (2019.08.19)
 ------------------

docs/setup.rst

@@ -18,6 +18,6 @@ Dependencies
 ============
 
 ``django-model-utils`` supports `Django`_ 1.8 through 2.1 (latest bugfix
-release in each series only) on Python 2.7, 3.4, 3.5 and 3.6.
+release in each series only) on Python 3.4, 3.5 and 3.6.
 
 .. _Django: http://www.djangoproject.com/

model_utils/choices.py

@@ -3,7 +3,7 @@ from __future__ import unicode_literals
 import copy
 
 
-class Choices(object):
+class Choices:
     """
     A class to encapsulate handy functionality for lists of choices
     for a Django model field.

model_utils/fields.py

@@ -5,7 +5,6 @@ import uuid
 from django.db import models
 from django.conf import settings
 from django.core.exceptions import ValidationError
-from django.utils.encoding import python_2_unicode_compatible
 from django.utils.timezone import now
 
 DEFAULT_CHOICES_NAME = 'STATUS'
@@ -178,8 +177,7 @@ def get_excerpt(content):
     return '\n'.join(default_excerpt)
 
 
-@python_2_unicode_compatible
-class SplitText(object):
+class SplitText:
     def __init__(self, instance, field_name, excerpt_field_name):
         # instead of storing actual values store a reference to the instance
         # along with field names, this makes assignment possible
@@ -210,7 +208,7 @@ class SplitText(object):
         return self.content
 
 
-class SplitDescriptor(object):
+class SplitDescriptor:
     def __init__(self, field):
         self.field = field
         self.excerpt_field_name = _excerpt_field_name(self.field.name)

model_utils/managers.py

@@ -44,7 +44,7 @@ class InheritanceIterable(ModelIterable):
                 yield obj
 
 
-class InheritanceQuerySetMixin(object):
+class InheritanceQuerySetMixin:
     def __init__(self, *args, **kwargs):
         super(InheritanceQuerySetMixin, self).__init__(*args, **kwargs)
         self._iterable_class = InheritanceIterable
@@ -216,7 +216,8 @@ class InheritanceQuerySet(InheritanceQuerySetMixin, QuerySet):
         
         return self.select_subclasses(*models).extra(where=[' OR '.join(where_queries)])
 
-class InheritanceManagerMixin(object):
+
+class InheritanceManagerMixin:
     _queryset_class = InheritanceQuerySet
 
     def get_queryset(self):
@@ -235,7 +236,7 @@ class InheritanceManager(InheritanceManagerMixin, models.Manager):
     pass
 
 
-class QueryManagerMixin(object):
+class QueryManagerMixin:
 
     def __init__(self, *args, **kwargs):
         if args:
@@ -260,7 +261,7 @@ class QueryManager(QueryManagerMixin, models.Manager):
     pass
 
 
-class SoftDeletableQuerySetMixin(object):
+class SoftDeletableQuerySetMixin:
     """
     QuerySet for SoftDeletableModel. Instead of removing instance sets
     its ``is_removed`` field to True.
@@ -278,7 +279,7 @@ class SoftDeletableQuerySet(SoftDeletableQuerySetMixin, QuerySet):
     pass
 
 
-class SoftDeletableManagerMixin(object):
+class SoftDeletableManagerMixin:
     """
     Manager that limits the queryset by default to show only not removed
     instances of model.
@@ -393,7 +394,7 @@ class JoinQueryset(models.QuerySet):
         return new_qs
 
 
-class JoinManagerMixin(object):
+class JoinManagerMixin:
     """
     Manager that adds a method join. This method allows you to join two
     querysets together.

model_utils/tracker.py

@@ -9,7 +9,7 @@ from django.db.models.fields.files import FileDescriptor
 from django.db.models.query_utils import DeferredAttribute
 
 
-class DescriptorMixin(object):
+class DescriptorMixin:
     tracker_instance = None
 
     def __get__(self, instance, owner):
@@ -29,7 +29,7 @@ class DescriptorMixin(object):
         return self.field_name
 
 
-class DescriptorWrapper(object):
+class DescriptorWrapper:
 
     def __init__(self, field_name, descriptor, tracker_attname):
         self.field_name = field_name
@@ -88,7 +88,7 @@ class FullDescriptorWrapper(DescriptorWrapper):
         self.descriptor.__delete__(obj)
 
 
-class FieldInstanceTracker(object):
+class FieldInstanceTracker:
     def __init__(self, instance, fields, field_map):
         self.instance = instance
         self.fields = fields
@@ -190,7 +190,7 @@ class FieldInstanceTracker(object):
                 setattr(self.instance.__class__, field, field_tracker)
 
 
-class FieldTracker(object):
+class FieldTracker:
 
     tracker_class = FieldInstanceTracker
 

setup.py

@@ -41,7 +41,6 @@ setup(
         'License :: OSI Approved :: BSD License',
         'Operating System :: OS Independent',
         'Programming Language :: Python',
-        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.6',

tests/models.py

@@ -4,7 +4,6 @@ import django
 from django.db import models
 from django.db.models.query_utils import DeferredAttribute
 from django.db.models import Manager
-from django.utils.encoding import python_2_unicode_compatible
 from django.utils.translation import ugettext_lazy as _
 
 from model_utils import Choices
@@ -36,7 +35,6 @@ class InheritanceManagerTestRelated(models.Model):
     pass
 
 
-@python_2_unicode_compatible
 class InheritanceManagerTestParent(models.Model):
     # FileField is just a handy descriptor-using field. Refs #6.
     non_related_field_using_descriptor = models.FileField(upload_to="test")
@@ -206,12 +204,12 @@ class NoRendered(models.Model):
     body = SplitField(no_excerpt_field=True)
 
 
-class AuthorMixin(object):
+class AuthorMixin:
     def by_author(self, name):
         return self.filter(author=name)
 
 
-class PublishedMixin(object):
+class PublishedMixin:
     def published(self):
         return self.filter(published=True)
 
@@ -373,7 +371,7 @@ class CustomSoftDelete(SoftDeletableModel):
     objects = CustomSoftDeleteManager()
 
 
-class StringyDescriptor(object):
+class StringyDescriptor:
     """
     Descriptor that returns a string version of the underlying integer value.
     """

tests/test_fields/test_field_tracker.py

@@ -45,7 +45,7 @@ class FieldTrackerTestCase(TestCase):
         self.instance.save()
 
 
-class FieldTrackerCommonTests(object):
+class FieldTrackerCommonTests:
 
     def test_pre_save_previous(self):
         self.assertPrevious(name=None, number=None)

tox.ini

@@ -1,6 +1,5 @@
 [tox]
 envlist =
-    py27-django{111}
     py37-django{202,201}
     py36-django{111,202,201,trunk}
     flake8