Refs #26022 -- Used context manager version of assertRaises in tests.

tests/admin_filters/tests.py

@@ -850,7 +850,8 @@ class ListFiltersTests(TestCase):
         """
         modeladmin = DecadeFilterBookAdminWithFailingQueryset(Book, site)
         request = self.request_factory.get('/', {})
-        self.assertRaises(ZeroDivisionError, self.get_changelist, request, Book, modeladmin)
+        with self.assertRaises(ZeroDivisionError):
+            self.get_changelist(request, Book, modeladmin)
 
     def test_simplelistfilter_with_queryset_based_lookups(self):
         modeladmin = DecadeFilterBookAdminWithQuerysetBasedLookups(Book, site)

tests/admin_registration/tests.py

@@ -36,9 +36,8 @@ class TestRegistration(SimpleTestCase):
 
     def test_prevent_double_registration(self):
         self.site.register(Person)
-        self.assertRaises(admin.sites.AlreadyRegistered,
-                          self.site.register,
-                          Person)
+        with self.assertRaises(admin.sites.AlreadyRegistered):
+            self.site.register(Person)
 
     def test_registration_with_star_star_options(self):
         self.site.register(Person, search_fields=['name'])
@@ -68,7 +67,8 @@ class TestRegistration(SimpleTestCase):
         Exception is raised when trying to register an abstract model.
         Refs #12004.
         """
-        self.assertRaises(ImproperlyConfigured, self.site.register, Location)
+        with self.assertRaises(ImproperlyConfigured):
+            self.site.register(Location)
 
     def test_is_registered_model(self):
         "Checks for registered models should return true."

tests/admin_utils/tests.py

@@ -221,10 +221,8 @@ class UtilsTests(SimpleTestCase):
             str("article")
         )
 
-        self.assertRaises(
-            AttributeError,
-            lambda: label_for_field("unknown", Article)
-        )
+        with self.assertRaises(AttributeError):
+            label_for_field("unknown", Article)
 
         def test_callable(obj):
             return "nothing"

tests/aggregation_regress/tests.py

@@ -376,20 +376,14 @@ class AggregationTests(TestCase):
 
     def test_field_error(self):
         # Bad field requests in aggregates are caught and reported
-        self.assertRaises(
-            FieldError,
-            lambda: Book.objects.all().aggregate(num_authors=Count('foo'))
-        )
+        with self.assertRaises(FieldError):
+            Book.objects.all().aggregate(num_authors=Count('foo'))
 
-        self.assertRaises(
-            FieldError,
-            lambda: Book.objects.all().annotate(num_authors=Count('foo'))
-        )
+        with self.assertRaises(FieldError):
+            Book.objects.all().annotate(num_authors=Count('foo'))
 
-        self.assertRaises(
-            FieldError,
-            lambda: Book.objects.all().annotate(num_authors=Count('authors__id')).aggregate(Max('foo'))
-        )
+        with self.assertRaises(FieldError):
+            Book.objects.all().annotate(num_authors=Count('authors__id')).aggregate(Max('foo'))
 
     def test_more(self):
         # Old-style count aggregations can be mixed with new-style
@@ -698,21 +692,20 @@ class AggregationTests(TestCase):
 
     def test_duplicate_alias(self):
         # Regression for #11256 - duplicating a default alias raises ValueError.
-        self.assertRaises(
-            ValueError,
-            Book.objects.all().annotate,
-            Avg('authors__age'), authors__age__avg=Avg('authors__age')
-        )
+        with self.assertRaises(ValueError):
+            Book.objects.all().annotate(Avg('authors__age'), authors__age__avg=Avg('authors__age'))
 
     def test_field_name_conflict(self):
         # Regression for #11256 - providing an aggregate name
         # that conflicts with a field name on the model raises ValueError
-        self.assertRaises(ValueError, Author.objects.annotate, age=Avg('friends__age'))
+        with self.assertRaises(ValueError):
+            Author.objects.annotate(age=Avg('friends__age'))
 
     def test_m2m_name_conflict(self):
         # Regression for #11256 - providing an aggregate name
         # that conflicts with an m2m name on the model raises ValueError
-        self.assertRaises(ValueError, Author.objects.annotate, friends=Count('friends'))
+        with self.assertRaises(ValueError):
+            Author.objects.annotate(friends=Count('friends'))
 
     def test_values_queryset_non_conflict(self):
         # Regression for #14707 -- If you're using a values query set, some potential conflicts are avoided.
@@ -739,7 +732,8 @@ class AggregationTests(TestCase):
     def test_reverse_relation_name_conflict(self):
         # Regression for #11256 - providing an aggregate name
         # that conflicts with a reverse-related name on the model raises ValueError
-        self.assertRaises(ValueError, Author.objects.annotate, book_contact_set=Avg('friends__age'))
+        with self.assertRaises(ValueError):
+            Author.objects.annotate(book_contact_set=Avg('friends__age'))
 
     def test_pickle(self):
         # Regression for #10197 -- Queries with aggregates can be pickled.
@@ -900,10 +894,8 @@ class AggregationTests(TestCase):
 
         # Regression for #10766 - Shouldn't be able to reference an aggregate
         # fields in an aggregate() call.
-        self.assertRaises(
-            FieldError,
-            lambda: Book.objects.annotate(mean_age=Avg('authors__age')).annotate(Avg('mean_age'))
-        )
+        with self.assertRaises(FieldError):
+            Book.objects.annotate(mean_age=Avg('authors__age')).annotate(Avg('mean_age'))
 
     def test_empty_filter_count(self):
         self.assertEqual(

tests/auth_tests/test_auth_backends.py

@@ -429,7 +429,8 @@ class NoBackendsTest(TestCase):
         self.user = User.objects.create_user('test', 'test@example.com', 'test')
 
     def test_raises_exception(self):
-        self.assertRaises(ImproperlyConfigured, self.user.has_perm, ('perm', TestObj(),))
+        with self.assertRaises(ImproperlyConfigured):
+            self.user.has_perm(('perm', TestObj()))
 
 
 @override_settings(AUTHENTICATION_BACKENDS=['auth_tests.test_auth_backends.SimpleRowlevelBackend'])
@@ -575,7 +576,8 @@ class TypeErrorBackendTest(TestCase):
 
     @override_settings(AUTHENTICATION_BACKENDS=[backend])
     def test_type_error_raised(self):
-        self.assertRaises(TypeError, authenticate, username='test', password='test')
+        with self.assertRaises(TypeError):
+            authenticate(username='test', password='test')
 
 
 class ImproperlyConfiguredUserModelTest(TestCase):
@@ -598,7 +600,8 @@ class ImproperlyConfiguredUserModelTest(TestCase):
         request = HttpRequest()
         request.session = self.client.session
 
-        self.assertRaises(ImproperlyConfigured, get_user, request)
+        with self.assertRaises(ImproperlyConfigured):
+            get_user(request)
 
 
 class ImportedModelBackend(ModelBackend):

tests/auth_tests/test_decorators.py

@@ -115,4 +115,5 @@ class PermissionsRequiredDecoratorTest(TestCase):
             return HttpResponse()
         request = self.factory.get('/rand')
         request.user = self.user
-        self.assertRaises(PermissionDenied, a_view, request)
+        with self.assertRaises(PermissionDenied):
+            a_view(request)

tests/auth_tests/test_hashers.py

@@ -219,7 +219,8 @@ class TestUtilsHashPass(SimpleTestCase):
         self.assertFalse(check_password('', encoded))
         self.assertFalse(check_password('lètmein', encoded))
         self.assertFalse(check_password('lètmeinz', encoded))
-        self.assertRaises(ValueError, identify_hasher, encoded)
+        with self.assertRaises(ValueError):
+            identify_hasher(encoded)
         # Assert that the unusable passwords actually contain a random part.
         # This might fail one day due to a hash collision.
         self.assertNotEqual(encoded, make_password(None), "Random password collision?")
@@ -234,7 +235,8 @@ class TestUtilsHashPass(SimpleTestCase):
     def test_bad_algorithm(self):
         with self.assertRaises(ValueError):
             make_password('lètmein', hasher='lolcat')
-        self.assertRaises(ValueError, identify_hasher, "lolcat$salt$hash")
+        with self.assertRaises(ValueError):
+            identify_hasher('lolcat$salt$hash')
 
     def test_bad_encoded(self):
         self.assertFalse(is_password_usable('lètmein_badencoded'))

tests/auth_tests/test_mixins.py

@@ -135,7 +135,8 @@ class UserPassesTestTests(TestCase):
 
         request = self.factory.get('/rand')
         request.user = AnonymousUser()
-        self.assertRaises(PermissionDenied, AView.as_view(), request)
+        with self.assertRaises(PermissionDenied):
+            AView.as_view()(request)
 
     def test_raise_exception_custom_message(self):
         msg = "You don't have access here"
@@ -248,4 +249,5 @@ class PermissionsRequiredMixinTests(TestCase):
 
         request = self.factory.get('/rand')
         request.user = self.user
-        self.assertRaises(PermissionDenied, AView.as_view(), request)
+        with self.assertRaises(PermissionDenied):
+            AView.as_view()(request)

tests/auth_tests/test_tokens.py

@@ -63,6 +63,5 @@ class TokenGeneratorTest(TestCase):
         p0 = PasswordResetTokenGenerator()
 
         # This will put a 14-digit base36 timestamp into the token, which is too large.
-        self.assertRaises(ValueError,
-                          p0._make_token_with_timestamp,
-                          user, 175455491841851871349)
+        with self.assertRaises(ValueError):
+            p0._make_token_with_timestamp(user, 175455491841851871349)

tests/backends/tests.py

@@ -128,19 +128,16 @@ class SQLiteTests(TestCase):
         #19360: Raise NotImplementedError when aggregating on date/time fields.
         """
         for aggregate in (Sum, Avg, Variance, StdDev):
-            self.assertRaises(
-                NotImplementedError,
-                models.Item.objects.all().aggregate, aggregate('time'))
-            self.assertRaises(
-                NotImplementedError,
-                models.Item.objects.all().aggregate, aggregate('date'))
-            self.assertRaises(
-                NotImplementedError,
-                models.Item.objects.all().aggregate, aggregate('last_modified'))
-            self.assertRaises(
-                NotImplementedError,
-                models.Item.objects.all().aggregate,
-                **{'complex': aggregate('last_modified') + aggregate('last_modified')})
+            with self.assertRaises(NotImplementedError):
+                models.Item.objects.all().aggregate(aggregate('time'))
+            with self.assertRaises(NotImplementedError):
+                models.Item.objects.all().aggregate(aggregate('date'))
+            with self.assertRaises(NotImplementedError):
+                models.Item.objects.all().aggregate(aggregate('last_modified'))
+            with self.assertRaises(NotImplementedError):
+                models.Item.objects.all().aggregate(
+                    **{'complex': aggregate('last_modified') + aggregate('last_modified')}
+                )
 
     def test_memory_db_test_name(self):
         """
@@ -449,8 +446,10 @@ class ParameterHandlingTest(TestCase):
             connection.ops.quote_name('root'),
             connection.ops.quote_name('square')
         ))
-        self.assertRaises(Exception, cursor.executemany, query, [(1, 2, 3)])
-        self.assertRaises(Exception, cursor.executemany, query, [(1,)])
+        with self.assertRaises(Exception):
+            cursor.executemany(query, [(1, 2, 3)])
+        with self.assertRaises(Exception):
+            cursor.executemany(query, [(1,)])
 
 
 # Unfortunately, the following tests would be a good test to run on all
@@ -859,7 +858,8 @@ class FkConstraintsTests(TransactionTestCase):
         a2 = models.Article(headline='This is another test', reporter=self.r,
                             pub_date=datetime.datetime(2012, 8, 3),
                             reporter_proxy_id=30)
-        self.assertRaises(IntegrityError, a2.save)
+        with self.assertRaises(IntegrityError):
+            a2.save()
 
     def test_integrity_checks_on_update(self):
         """
@@ -887,7 +887,8 @@ class FkConstraintsTests(TransactionTestCase):
         # Retrieve the second article from the DB
         a2 = models.Article.objects.get(headline='Another article')
         a2.reporter_proxy_id = 30
-        self.assertRaises(IntegrityError, a2.save)
+        with self.assertRaises(IntegrityError):
+            a2.save()
 
     def test_disable_constraint_checks_manually(self):
         """

tests/basic/tests.py

@@ -499,12 +499,8 @@ class ModelLookupTest(TestCase):
         )
         # To avoid dict-ordering related errors check only one lookup
         # in single assert.
-        self.assertRaises(
-            ObjectDoesNotExist,
-            Article.objects.get,
-            pub_date__year=2005,
-            pub_date__month=8,
-        )
+        with self.assertRaises(ObjectDoesNotExist):
+            Article.objects.get(pub_date__year=2005, pub_date__month=8)
         six.assertRaisesRegex(
             self,
             ObjectDoesNotExist,

tests/cache/tests.py

@@ -129,14 +129,18 @@ class DummyCacheTests(SimpleTestCase):
     def test_incr(self):
         "Dummy cache values can't be incremented"
         cache.set('answer', 42)
-        self.assertRaises(ValueError, cache.incr, 'answer')
-        self.assertRaises(ValueError, cache.incr, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.incr('answer')
+        with self.assertRaises(ValueError):
+            cache.incr('does_not_exist')
 
     def test_decr(self):
         "Dummy cache values can't be decremented"
         cache.set('answer', 42)
-        self.assertRaises(ValueError, cache.decr, 'answer')
-        self.assertRaises(ValueError, cache.decr, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.decr('answer')
+        with self.assertRaises(ValueError):
+            cache.decr('does_not_exist')
 
     def test_data_types(self):
         "All data types are ignored equally by the dummy cache"
@@ -193,14 +197,18 @@ class DummyCacheTests(SimpleTestCase):
     def test_incr_version(self):
         "Dummy cache versions can't be incremented"
         cache.set('answer', 42)
-        self.assertRaises(ValueError, cache.incr_version, 'answer')
-        self.assertRaises(ValueError, cache.incr_version, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.incr_version('answer')
+        with self.assertRaises(ValueError):
+            cache.incr_version('does_not_exist')
 
     def test_decr_version(self):
         "Dummy cache versions can't be decremented"
         cache.set('answer', 42)
-        self.assertRaises(ValueError, cache.decr_version, 'answer')
-        self.assertRaises(ValueError, cache.decr_version, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.decr_version('answer')
+        with self.assertRaises(ValueError):
+            cache.decr_version('does_not_exist')
 
     def test_get_or_set(self):
         self.assertEqual(cache.get_or_set('mykey', 'default'), 'default')
@@ -321,7 +329,8 @@ class BaseCacheTests(object):
         self.assertEqual(cache.incr('answer', 10), 52)
         self.assertEqual(cache.get('answer'), 52)
         self.assertEqual(cache.incr('answer', -10), 42)
-        self.assertRaises(ValueError, cache.incr, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.incr('does_not_exist')
 
     def test_decr(self):
         # Cache values can be decremented
@@ -331,7 +340,8 @@ class BaseCacheTests(object):
         self.assertEqual(cache.decr('answer', 10), 32)
         self.assertEqual(cache.get('answer'), 32)
         self.assertEqual(cache.decr('answer', -10), 42)
-        self.assertRaises(ValueError, cache.decr, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.decr('does_not_exist')
 
     def test_close(self):
         self.assertTrue(hasattr(cache, 'close'))
@@ -821,7 +831,8 @@ class BaseCacheTests(object):
         self.assertIsNone(caches['v2'].get('answer2', version=2))
         self.assertEqual(caches['v2'].get('answer2', version=3), 42)
 
-        self.assertRaises(ValueError, cache.incr_version, 'does_not_exist')
+        with self.assertRaises(ValueError):
+            cache.incr_version('does_not_exist')
 
     def test_decr_version(self):
         cache.set('answer', 42, version=2)
@@ -844,7 +855,8 @@ class BaseCacheTests(object):
         self.assertEqual(caches['v2'].get('answer2', version=1), 42)
         self.assertIsNone(caches['v2'].get('answer2', version=2))
 
-        self.assertRaises(ValueError, cache.decr_version, 'does_not_exist', version=2)
+        with self.assertRaises(ValueError):
+            cache.decr_version('does_not_exist', version=2)
 
     def test_custom_key_func(self):
         # Two caches with different key functions aren't visible to each other
@@ -1138,9 +1150,11 @@ class MemcachedCacheTests(BaseCacheTests, TestCase):
         that a generic exception of some kind is raised.
         """
         # memcached does not allow whitespace or control characters in keys
-        self.assertRaises(Exception, cache.set, 'key with spaces', 'value')
+        with self.assertRaises(Exception):
+            cache.set('key with spaces', 'value')
         # memcached limits key length to 250
-        self.assertRaises(Exception, cache.set, 'a' * 251, 'value')
+        with self.assertRaises(Exception):
+            cache.set('a' * 251, 'value')
 
     # Explicitly display a skipped test if no configured cache uses MemcachedCache
     @unittest.skipUnless(

tests/check_framework/tests.py

@@ -161,7 +161,8 @@ class CheckCommandTests(SimpleTestCase):
 
     @override_system_checks([simple_system_check, tagged_system_check])
     def test_invalid_tag(self):
-        self.assertRaises(CommandError, call_command, 'check', tags=['missingtag'])
+        with self.assertRaises(CommandError):
+            call_command('check', tags=['missingtag'])
 
     @override_system_checks([simple_system_check])
     def test_list_tags_empty(self):

tests/contenttypes_tests/test_models.py

@@ -208,7 +208,8 @@ class ContentTypesTests(TestCase):
         user_ct = ContentType.objects.get_for_model(FooWithoutUrl)
         obj = FooWithoutUrl.objects.create(name="john")
 
-        self.assertRaises(Http404, shortcut, request, user_ct.id, obj.id)
+        with self.assertRaises(Http404):
+            shortcut(request, user_ct.id, obj.id)
 
     def test_shortcut_view_with_broken_get_absolute_url(self):
         """
@@ -224,7 +225,8 @@ class ContentTypesTests(TestCase):
         user_ct = ContentType.objects.get_for_model(FooWithBrokenAbsoluteUrl)
         obj = FooWithBrokenAbsoluteUrl.objects.create(name="john")
 
-        self.assertRaises(AttributeError, shortcut, request, user_ct.id, obj.id)
+        with self.assertRaises(AttributeError):
+            shortcut(request, user_ct.id, obj.id)
 
     def test_missing_model(self):
         """

tests/custom_columns/tests.py

@@ -40,10 +40,8 @@ class CustomColumnsTests(TestCase):
         )
 
     def test_field_error(self):
-        self.assertRaises(
-            FieldError,
-            lambda: Author.objects.filter(firstname__exact="John")
-        )
+        with self.assertRaises(FieldError):
+            Author.objects.filter(firstname__exact="John")
 
     def test_attribute_error(self):
         with self.assertRaises(AttributeError):

tests/custom_managers/tests.py

@@ -115,7 +115,8 @@ class CustomManagerTests(TestCase):
         The default manager, "objects", doesn't exist, because a custom one
         was provided.
         """
-        self.assertRaises(AttributeError, lambda: Book.objects)
+        with self.assertRaises(AttributeError):
+            Book.objects
 
     def test_filtering(self):
         """

tests/custom_pk/tests.py

@@ -131,10 +131,8 @@ class BasicCustomPKTests(TestCase):
         self.assertEqual(Employee.objects.get(pk=123), self.dan)
         self.assertEqual(Employee.objects.get(pk=456), self.fran)
 
-        self.assertRaises(
-            Employee.DoesNotExist,
-            lambda: Employee.objects.get(pk=42)
-        )
+        with self.assertRaises(Employee.DoesNotExist):
+            Employee.objects.get(pk=42)
 
         # Use the name of the primary key, rather than pk.
         self.assertEqual(Employee.objects.get(employee_code=123), self.dan)
@@ -151,7 +149,8 @@ class BasicCustomPKTests(TestCase):
         # Or we can use the real attribute name for the primary key:
         self.assertEqual(e.employee_code, 123)
 
-        self.assertRaises(AttributeError, lambda: e.id)
+        with self.assertRaises(AttributeError):
+            e.id
 
     def test_in_bulk(self):
         """

tests/datatypes/tests.py

@@ -82,8 +82,9 @@ class DataTypesTestCase(TestCase):
         an error if given a timezone-aware datetime object."""
         dt = datetime.datetime(2008, 8, 31, 16, 20, tzinfo=utc)
         d = Donut(name='Bear claw', consumed_at=dt)
-        self.assertRaises(ValueError, d.save)
-        # ValueError: MySQL backend does not support timezone-aware datetimes.
+        # MySQL backend does not support timezone-aware datetimes.
+        with self.assertRaises(ValueError):
+            d.save()
 
     def test_datefield_auto_now_add(self):
         """Regression test for #10970, auto_now_add for DateField should store

tests/dates/tests.py

@@ -87,10 +87,8 @@ class DatesTests(TestCase):
         )
 
     def test_dates_fails_when_no_arguments_are_provided(self):
-        self.assertRaises(
-            TypeError,
-            Article.objects.dates,
-        )
+        with self.assertRaises(TypeError):
+            Article.objects.dates()
 
     def test_dates_fails_when_given_invalid_field_argument(self):
         six.assertRaisesRegex(

tests/delete/tests.py

@@ -63,7 +63,8 @@ class OnDeleteTests(TestCase):
 
     def test_protect(self):
         a = create_a('protect')
-        self.assertRaises(IntegrityError, a.protect.delete)
+        with self.assertRaises(IntegrityError):
+            a.protect.delete()
 
     def test_do_nothing(self):
         # Testing DO_NOTHING is a bit harder: It would raise IntegrityError for a normal model,

tests/expressions/tests.py

@@ -294,12 +294,14 @@ class BasicExpressionsTests(TestCase):
 
         def test():
             test_gmbh.point_of_contact = F("ceo")
-        self.assertRaises(ValueError, test)
+        with self.assertRaises(ValueError):
+            test()
 
         test_gmbh.point_of_contact = test_gmbh.ceo
         test_gmbh.save()
         test_gmbh.name = F("ceo__last_name")
-        self.assertRaises(FieldError, test_gmbh.save)
+        with self.assertRaises(FieldError):
+            test_gmbh.save()
 
     def test_object_update_unsaved_objects(self):
         # F expressions cannot be used to update attributes on objects which do

tests/file_storage/tests.py

@@ -52,8 +52,8 @@ class GetStorageClassTests(SimpleTestCase):
         """
         get_storage_class raises an error if the requested class don't exist.
         """
-        self.assertRaises(ImportError, get_storage_class,
-                          'django.core.files.storage.NonExistingStorage')
+        with self.assertRaises(ImportError):
+            get_storage_class('django.core.files.storage.NonExistingStorage')
 
     def test_get_nonexisting_storage_module(self):
         """
@@ -256,7 +256,8 @@ class FileStorageTests(SimpleTestCase):
             """/test_media_url/a/b/c.file""")
 
         self.storage.base_url = None
-        self.assertRaises(ValueError, self.storage.url, 'test.file')
+        with self.assertRaises(ValueError):
+            self.storage.url('test.file')
 
         # #22717: missing ending slash in base_url should be auto-corrected
         storage = self.storage_class(location=self.temp_dir,
@@ -292,8 +293,10 @@ class FileStorageTests(SimpleTestCase):
         File storage prevents directory traversal (files can only be accessed if
         they're below the storage location).
         """
-        self.assertRaises(SuspiciousOperation, self.storage.exists, '..')
-        self.assertRaises(SuspiciousOperation, self.storage.exists, '/etc/passwd')
+        with self.assertRaises(SuspiciousOperation):
+            self.storage.exists('..')
+        with self.assertRaises(SuspiciousOperation):
+            self.storage.exists('/etc/passwd')
 
     def test_file_storage_preserves_filename_case(self):
         """The storage backend should preserve case of filenames."""
@@ -342,8 +345,8 @@ class FileStorageTests(SimpleTestCase):
                 self.assertEqual(f.read(), b'saved with race')
 
             # Check that OSErrors aside from EEXIST are still raised.
-            self.assertRaises(OSError,
-                self.storage.save, 'error/test.file', ContentFile('not saved'))
+            with self.assertRaises(OSError):
+                self.storage.save('error/test.file', ContentFile('not saved'))
         finally:
             os.makedirs = real_makedirs
 
@@ -379,7 +382,8 @@ class FileStorageTests(SimpleTestCase):
 
             # Check that OSErrors aside from ENOENT are still raised.
             self.storage.save('error.file', ContentFile('delete with error'))
-            self.assertRaises(OSError, self.storage.delete, 'error.file')
+            with self.assertRaises(OSError):
+                self.storage.delete('error.file')
         finally:
             os.remove = real_remove
 
@@ -491,7 +495,8 @@ class FileFieldStorageTests(TestCase):
         # An object without a file has limited functionality.
         obj1 = Storage()
         self.assertEqual(obj1.normal.name, "")
-        self.assertRaises(ValueError, lambda: obj1.normal.size)
+        with self.assertRaises(ValueError):
+            obj1.normal.size
 
         # Saving a file enables full functionality.
         obj1.normal.save("django_test.txt", ContentFile("content"))

tests/file_uploads/tests.py

@@ -376,12 +376,8 @@ class FileUploadTests(TestCase):
             file.seek(0)
 
             # AttributeError: You cannot alter upload handlers after the upload has been processed.
-            self.assertRaises(
-                AttributeError,
-                self.client.post,
-                '/quota/broken/',
-                {'f': file}
-            )
+            with self.assertRaises(AttributeError):
+                self.client.post('/quota/broken/', {'f': file})
 
     def test_fileupload_getlist(self):
         file = tempfile.NamedTemporaryFile

tests/files/tests.py

@@ -287,7 +287,8 @@ class FileMoveSafeTests(unittest.TestCase):
         handle_b, self.file_b = tempfile.mkstemp()
 
         # file_move_safe should raise an IOError exception if destination file exists and allow_overwrite is False
-        self.assertRaises(IOError, lambda: file_move_safe(self.file_a, self.file_b, allow_overwrite=False))
+        with self.assertRaises(IOError):
+            file_move_safe(self.file_a, self.file_b, allow_overwrite=False)
 
         # should allow it and continue on if allow_overwrite is True
         self.assertIsNone(file_move_safe(self.file_a, self.file_b, allow_overwrite=True))

tests/flatpages_tests/test_templatetags.py

@@ -144,17 +144,17 @@ class FlatpageTemplateTagTests(TestCase):
         def render(t):
             return Template(t).render(Context())
 
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages %}")
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages as %}")
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages cheesecake flatpages %}")
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages as flatpages asdf %}")
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages cheesecake user as flatpages %}")
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages for user as flatpages asdf %}")
-        self.assertRaises(TemplateSyntaxError, render,
-                          "{% load flatpages %}{% get_flatpages prefix for user as flatpages asdf %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages as %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages cheesecake flatpages %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages as flatpages asdf %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages cheesecake user as flatpages %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages for user as flatpages asdf %}")
+        with self.assertRaises(TemplateSyntaxError):
+            render("{% load flatpages %}{% get_flatpages prefix for user as flatpages asdf %}")

tests/foreign_object/tests.py

@@ -57,7 +57,8 @@ class MultiColumnFKTests(TestCase):
         membership = Membership.objects.create(
             membership_country_id=self.usa.id, person_id=self.jane.id, group_id=self.cia.id)
 
-        self.assertRaises(Person.DoesNotExist, getattr, membership, 'person')
+        with self.assertRaises(Person.DoesNotExist):
+            getattr(membership, 'person')
 
     def test_reverse_query_returns_correct_result(self):
         # Creating a valid membership because it has the same country has the person

tests/forms_tests/tests/test_fields.py

@@ -149,9 +149,12 @@ class FieldsTests(SimpleTestCase):
         Ensure that setting min_length or max_length to something that is not a
         number returns an exception.
         """
-        self.assertRaises(ValueError, CharField, min_length='a')
-        self.assertRaises(ValueError, CharField, max_length='a')
-        self.assertRaises(ValueError, CharField, 'a')
+        with self.assertRaises(ValueError):
+            CharField(min_length='a')
+        with self.assertRaises(ValueError):
+            CharField(max_length='a')
+        with self.assertRaises(ValueError):
+            CharField('a')
 
     def test_charfield_widget_attrs(self):
         """
@@ -1654,8 +1657,10 @@ class FieldsTests(SimpleTestCase):
     # GenericIPAddressField #######################################################
 
     def test_generic_ipaddress_invalid_arguments(self):
-        self.assertRaises(ValueError, GenericIPAddressField, protocol="hamster")
-        self.assertRaises(ValueError, GenericIPAddressField, protocol="ipv4", unpack_ipv4=True)
+        with self.assertRaises(ValueError):
+            GenericIPAddressField(protocol='hamster')
+        with self.assertRaises(ValueError):
+            GenericIPAddressField(protocol='ipv4', unpack_ipv4=True)
 
     def test_generic_ipaddress_as_generic(self):
         # The edge cases of the IPv6 validation code are not deeply tested

tests/forms_tests/tests/test_forms.py

@@ -3227,7 +3227,8 @@ Good luck picking a username that doesn&#39;t already exist.</p>
         """
         p = Person({'first_name': 'John', 'last_name': 'Lennon', 'birthday': 'fakedate'})
         repr(p)
-        self.assertRaises(AttributeError, lambda: p.cleaned_data)
+        with self.assertRaises(AttributeError):
+            p.cleaned_data
         self.assertFalse(p.is_valid())
         self.assertEqual(p.cleaned_data, {'first_name': 'John', 'last_name': 'Lennon'})
 

tests/forms_tests/tests/test_input_formats.py

@@ -19,7 +19,8 @@ class LocalizedTimeTests(SimpleTestCase):
         "TimeFields can parse dates in the default format"
         f = forms.TimeField()
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13:30:05')
@@ -45,7 +46,8 @@ class LocalizedTimeTests(SimpleTestCase):
         "Localized TimeFields act as unlocalized widgets"
         f = forms.TimeField(localize=True)
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13:30:05')
@@ -67,8 +69,10 @@ class LocalizedTimeTests(SimpleTestCase):
         "TimeFields with manually specified input formats can accept those formats"
         f = forms.TimeField(input_formats=["%H.%M.%S", "%H.%M"])
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13.30.05')
@@ -90,8 +94,10 @@ class LocalizedTimeTests(SimpleTestCase):
         "Localized TimeFields with manually specified input formats can accept those formats"
         f = forms.TimeField(input_formats=["%H.%M.%S", "%H.%M"], localize=True)
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13.30.05')
@@ -116,7 +122,8 @@ class CustomTimeInputFormatsTests(SimpleTestCase):
         "TimeFields can parse dates in the default format"
         f = forms.TimeField()
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('1:30:05 PM')
@@ -138,7 +145,8 @@ class CustomTimeInputFormatsTests(SimpleTestCase):
         "Localized TimeFields act as unlocalized widgets"
         f = forms.TimeField(localize=True)
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('1:30:05 PM')
@@ -160,8 +168,10 @@ class CustomTimeInputFormatsTests(SimpleTestCase):
         "TimeFields with manually specified input formats can accept those formats"
         f = forms.TimeField(input_formats=["%H.%M.%S", "%H.%M"])
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13.30.05')
@@ -183,8 +193,10 @@ class CustomTimeInputFormatsTests(SimpleTestCase):
         "Localized TimeFields with manually specified input formats can accept those formats"
         f = forms.TimeField(input_formats=["%H.%M.%S", "%H.%M"], localize=True)
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13.30.05')
@@ -208,7 +220,8 @@ class SimpleTimeFormatTests(SimpleTestCase):
         "TimeFields can parse dates in the default format"
         f = forms.TimeField()
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13:30:05')
@@ -230,7 +243,8 @@ class SimpleTimeFormatTests(SimpleTestCase):
         "Localized TimeFields in a non-localized environment act as unlocalized widgets"
         f = forms.TimeField()
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('13:30:05')
@@ -252,7 +266,8 @@ class SimpleTimeFormatTests(SimpleTestCase):
         "TimeFields with manually specified input formats can accept those formats"
         f = forms.TimeField(input_formats=["%I:%M:%S %p", "%I:%M %p"])
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('1:30:05 PM')
@@ -274,7 +289,8 @@ class SimpleTimeFormatTests(SimpleTestCase):
         "Localized TimeFields with manually specified input formats can accept those formats"
         f = forms.TimeField(input_formats=["%I:%M:%S %p", "%I:%M %p"], localize=True)
         # Parse a time in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05')
 
         # Parse a time in a valid format, get a parsed result
         result = f.clean('1:30:05 PM')
@@ -305,7 +321,8 @@ class LocalizedDateTests(SimpleTestCase):
         "DateFields can parse dates in the default format"
         f = forms.DateField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21/12/2010')
 
         # ISO formats are accepted, even if not specified in formats.py
         self.assertEqual(f.clean('2010-12-21'), date(2010, 12, 21))
@@ -330,7 +347,8 @@ class LocalizedDateTests(SimpleTestCase):
         "Localized DateFields act as unlocalized widgets"
         f = forms.DateField(localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21/12/2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('21.12.2010')
@@ -352,9 +370,12 @@ class LocalizedDateTests(SimpleTestCase):
         "DateFields with manually specified input formats can accept those formats"
         f = forms.DateField(input_formats=["%m.%d.%Y", "%m-%d-%Y"])
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
-        self.assertRaises(forms.ValidationError, f.clean, '21/12/2010')
-        self.assertRaises(forms.ValidationError, f.clean, '21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('12.21.2010')
@@ -376,9 +397,12 @@ class LocalizedDateTests(SimpleTestCase):
         "Localized DateFields with manually specified input formats can accept those formats"
         f = forms.DateField(input_formats=["%m.%d.%Y", "%m-%d-%Y"], localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
-        self.assertRaises(forms.ValidationError, f.clean, '21/12/2010')
-        self.assertRaises(forms.ValidationError, f.clean, '21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('12.21.2010')
@@ -403,7 +427,8 @@ class CustomDateInputFormatsTests(SimpleTestCase):
         "DateFields can parse dates in the default format"
         f = forms.DateField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('21.12.2010')
@@ -425,7 +450,8 @@ class CustomDateInputFormatsTests(SimpleTestCase):
         "Localized DateFields act as unlocalized widgets"
         f = forms.DateField(localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('21.12.2010')
@@ -447,8 +473,10 @@ class CustomDateInputFormatsTests(SimpleTestCase):
         "DateFields with manually specified input formats can accept those formats"
         f = forms.DateField(input_formats=["%m.%d.%Y", "%m-%d-%Y"])
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '21.12.2010')
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('12.21.2010')
@@ -470,8 +498,10 @@ class CustomDateInputFormatsTests(SimpleTestCase):
         "Localized DateFields with manually specified input formats can accept those formats"
         f = forms.DateField(input_formats=["%m.%d.%Y", "%m-%d-%Y"], localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '21.12.2010')
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('12.21.2010')
@@ -495,7 +525,8 @@ class SimpleDateFormatTests(SimpleTestCase):
         "DateFields can parse dates in the default format"
         f = forms.DateField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('2010-12-21')
@@ -517,7 +548,8 @@ class SimpleDateFormatTests(SimpleTestCase):
         "Localized DateFields in a non-localized environment act as unlocalized widgets"
         f = forms.DateField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('2010-12-21')
@@ -539,7 +571,8 @@ class SimpleDateFormatTests(SimpleTestCase):
         "DateFields with manually specified input formats can accept those formats"
         f = forms.DateField(input_formats=["%d.%m.%Y", "%d-%m-%Y"])
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('21.12.2010')
@@ -561,7 +594,8 @@ class SimpleDateFormatTests(SimpleTestCase):
         "Localized DateFields with manually specified input formats can accept those formats"
         f = forms.DateField(input_formats=["%d.%m.%Y", "%d-%m-%Y"], localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('21.12.2010')
@@ -592,7 +626,8 @@ class LocalizedDateTimeTests(SimpleTestCase):
         "DateTimeFields can parse dates in the default format"
         f = forms.DateTimeField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM 21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM 21/12/2010')
 
         # ISO formats are accepted, even if not specified in formats.py
         self.assertEqual(f.clean('2010-12-21 13:30:05'), datetime(2010, 12, 21, 13, 30, 5))
@@ -617,7 +652,8 @@ class LocalizedDateTimeTests(SimpleTestCase):
         "Localized DateTimeFields act as unlocalized widgets"
         f = forms.DateTimeField(localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM 21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM 21/12/2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('21.12.2010 13:30:05')
@@ -639,9 +675,12 @@ class LocalizedDateTimeTests(SimpleTestCase):
         "DateTimeFields with manually specified input formats can accept those formats"
         f = forms.DateTimeField(input_formats=["%H.%M.%S %m.%d.%Y", "%H.%M %m-%d-%Y"])
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05 13:30:05')
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM 21/12/2010')
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05 21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM 21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05 21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('13.30.05 12.21.2010')
@@ -663,9 +702,12 @@ class LocalizedDateTimeTests(SimpleTestCase):
         "Localized DateTimeFields with manually specified input formats can accept those formats"
         f = forms.DateTimeField(input_formats=["%H.%M.%S %m.%d.%Y", "%H.%M %m-%d-%Y"], localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
-        self.assertRaises(forms.ValidationError, f.clean, '1:30:05 PM 21/12/2010')
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05 21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('1:30:05 PM 21/12/2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05 21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('13.30.05 12.21.2010')
@@ -690,7 +732,8 @@ class CustomDateTimeInputFormatsTests(SimpleTestCase):
         "DateTimeFields can parse dates in the default format"
         f = forms.DateTimeField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('1:30:05 PM 21/12/2010')
@@ -712,7 +755,8 @@ class CustomDateTimeInputFormatsTests(SimpleTestCase):
         "Localized DateTimeFields act as unlocalized widgets"
         f = forms.DateTimeField(localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('1:30:05 PM 21/12/2010')
@@ -734,8 +778,10 @@ class CustomDateTimeInputFormatsTests(SimpleTestCase):
         "DateTimeFields with manually specified input formats can accept those formats"
         f = forms.DateTimeField(input_formats=["%m.%d.%Y %H:%M:%S", "%m-%d-%Y %H:%M"])
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05 21.12.2010')
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05 21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('12.21.2010 13:30:05')
@@ -757,8 +803,10 @@ class CustomDateTimeInputFormatsTests(SimpleTestCase):
         "Localized DateTimeFields with manually specified input formats can accept those formats"
         f = forms.DateTimeField(input_formats=["%m.%d.%Y %H:%M:%S", "%m-%d-%Y %H:%M"], localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05 21.12.2010')
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05 21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('12.21.2010 13:30:05')
@@ -782,7 +830,8 @@ class SimpleDateTimeFormatTests(SimpleTestCase):
         "DateTimeFields can parse dates in the default format"
         f = forms.DateTimeField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05 21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05 21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('2010-12-21 13:30:05')
@@ -804,7 +853,8 @@ class SimpleDateTimeFormatTests(SimpleTestCase):
         "Localized DateTimeFields in a non-localized environment act as unlocalized widgets"
         f = forms.DateTimeField()
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '13:30:05 21.12.2010')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('13:30:05 21.12.2010')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('2010-12-21 13:30:05')
@@ -826,7 +876,8 @@ class SimpleDateTimeFormatTests(SimpleTestCase):
         "DateTimeFields with manually specified input formats can accept those formats"
         f = forms.DateTimeField(input_formats=["%I:%M:%S %p %d.%m.%Y", "%I:%M %p %d-%m-%Y"])
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('1:30:05 PM 21.12.2010')
@@ -848,7 +899,8 @@ class SimpleDateTimeFormatTests(SimpleTestCase):
         "Localized DateTimeFields with manually specified input formats can accept those formats"
         f = forms.DateTimeField(input_formats=["%I:%M:%S %p %d.%m.%Y", "%I:%M %p %d-%m-%Y"], localize=True)
         # Parse a date in an unaccepted format; get an error
-        self.assertRaises(forms.ValidationError, f.clean, '2010-12-21 13:30:05')
+        with self.assertRaises(forms.ValidationError):
+            f.clean('2010-12-21 13:30:05')
 
         # Parse a date in a valid format, get a parsed result
         result = f.clean('1:30:05 PM 21.12.2010')

tests/forms_tests/tests/test_validators.py

@@ -45,12 +45,9 @@ class TestFieldWithValidators(TestCase):
             'string': '2 is not correct',
             'ignore_case_string': "IgnORE Case strIng",
         })
-        self.assertRaises(ValidationError, form.fields['full_name'].clean, 'not int nor mail')
-
-        try:
+        with self.assertRaises(ValidationError) as e:
             form.fields['full_name'].clean('not int nor mail')
-        except ValidationError as e:
-            self.assertEqual(2, len(e.messages))
+        self.assertEqual(2, len(e.exception.messages))
 
         self.assertFalse(form.is_valid())
         self.assertEqual(form.errors['string'], ["Letters only."])

tests/forms_tests/tests/tests.py

@@ -251,7 +251,8 @@ class RelatedModelFormTests(SimpleTestCase):
             model = A
             fields = '__all__'
 
-        self.assertRaises(ValueError, ModelFormMetaclass, str('Form'), (ModelForm,), {'Meta': Meta})
+        with self.assertRaises(ValueError):
+            ModelFormMetaclass(str('Form'), (ModelForm,), {'Meta': Meta})
 
         class B(models.Model):
             pass

tests/generic_relations_regress/tests.py

@@ -111,7 +111,8 @@ class GenericRelationTests(TestCase):
         # Fails with another, ORM-level error
         dev1 = Developer(name='Joe')
         note = Note(note='Deserves promotion', content_object=dev1)
-        self.assertRaises(IntegrityError, note.save)
+        with self.assertRaises(IntegrityError):
+            note.save()
 
     def test_target_model_len_zero(self):
         """Test for #13085 -- __len__() returns 0"""

tests/generic_views/test_base.py

@@ -145,12 +145,14 @@ class ViewTest(unittest.TestCase):
         # Check each of the allowed method names
         for method in SimpleView.http_method_names:
             kwargs = dict(((method, "value"),))
-            self.assertRaises(TypeError, SimpleView.as_view, **kwargs)
+            with self.assertRaises(TypeError):
+                SimpleView.as_view(**kwargs)
 
         # Check the case view argument is ok if predefined on the class...
         CustomizableView.as_view(parameter="value")
         # ...but raises errors otherwise.
-        self.assertRaises(TypeError, CustomizableView.as_view, foobar="value")
+        with self.assertRaises(TypeError):
+            CustomizableView.as_view(foobar="value")
 
     def test_calling_more_than_once(self):
         """
@@ -280,7 +282,8 @@ class TemplateViewTest(SimpleTestCase):
         """
         A template view must provide a template name.
         """
-        self.assertRaises(ImproperlyConfigured, self.client.get, '/template/no_template/')
+        with self.assertRaises(ImproperlyConfigured):
+            self.client.get('/template/no_template/')
 
     @require_jinja2
     def test_template_engine(self):
@@ -527,4 +530,5 @@ class SingleObjectTemplateResponseMixinTest(unittest.TestCase):
         TemplateDoesNotExist.
         """
         view = views.TemplateResponseWithoutTemplate()
-        self.assertRaises(ImproperlyConfigured, view.get_template_names)
+        with self.assertRaises(ImproperlyConfigured):
+            view.get_template_names()

tests/generic_views/test_dates.py

@@ -82,7 +82,8 @@ class ArchiveIndexViewTests(TestDataMixin, TestCase):
         self.assertTemplateUsed(res, 'generic_views/book_detail.html')
 
     def test_archive_view_invalid(self):
-        self.assertRaises(ImproperlyConfigured, self.client.get, '/dates/books/invalid/')
+        with self.assertRaises(ImproperlyConfigured):
+            self.client.get('/dates/books/invalid/')
 
     def test_archive_view_by_month(self):
         res = self.client.get('/dates/books/by_month/')
@@ -664,7 +665,8 @@ class DateDetailViewTests(TestDataMixin, TestCase):
         self.assertTemplateUsed(res, 'generic_views/book_detail.html')
 
     def test_invalid_url(self):
-        self.assertRaises(AttributeError, self.client.get, "/dates/books/2008/oct/01/nopk/")
+        with self.assertRaises(AttributeError):
+            self.client.get("/dates/books/2008/oct/01/nopk/")
 
     def test_get_object_custom_queryset(self):
         """

tests/generic_views/test_detail.py

@@ -49,7 +49,8 @@ class DetailViewTest(TestCase):
         self.assertEqual(res.status_code, 404)
 
     def test_detail_object_does_not_exist(self):
-        self.assertRaises(ObjectDoesNotExist, self.client.get, '/detail/doesnotexist/1/')
+        with self.assertRaises(ObjectDoesNotExist):
+            self.client.get('/detail/doesnotexist/1/')
 
     def test_detail_by_custom_pk(self):
         res = self.client.get('/detail/author/bycustompk/%s/' % self.author1.pk)
@@ -173,10 +174,12 @@ class DetailViewTest(TestCase):
         self.assertEqual(form_context_data['author'], self.author1)
 
     def test_invalid_url(self):
-        self.assertRaises(AttributeError, self.client.get, '/detail/author/invalid/url/')
+        with self.assertRaises(AttributeError):
+            self.client.get('/detail/author/invalid/url/')
 
     def test_invalid_queryset(self):
-        self.assertRaises(ImproperlyConfigured, self.client.get, '/detail/author/invalid/qs/')
+        with self.assertRaises(ImproperlyConfigured):
+            self.client.get('/detail/author/invalid/qs/')
 
     def test_non_model_object_with_meta(self):
         res = self.client.get('/detail/nonmodel/1/')

tests/generic_views/test_list.py

@@ -204,7 +204,8 @@ class ListViewTests(TestCase):
         self.assertTemplateUsed(res, 'generic_views/author_list.html')
 
     def test_missing_items(self):
-        self.assertRaises(ImproperlyConfigured, self.client.get, '/list/authors/invalid/')
+        with self.assertRaises(ImproperlyConfigured):
+            self.client.get('/list/authors/invalid/')
 
     def test_paginated_list_view_does_not_load_entire_table(self):
         # Regression test for #17535

tests/get_earliest_or_latest/tests.py

@@ -17,7 +17,8 @@ class EarliestOrLatestTests(TestCase):
 
     def test_earliest(self):
         # Because no Articles exist yet, earliest() raises ArticleDoesNotExist.
-        self.assertRaises(Article.DoesNotExist, Article.objects.earliest)
+        with self.assertRaises(Article.DoesNotExist):
+            Article.objects.earliest()
 
         a1 = Article.objects.create(
             headline="Article 1", pub_date=datetime(2005, 7, 26),
@@ -66,7 +67,8 @@ class EarliestOrLatestTests(TestCase):
 
     def test_latest(self):
         # Because no Articles exist yet, latest() raises ArticleDoesNotExist.
-        self.assertRaises(Article.DoesNotExist, Article.objects.latest)
+        with self.assertRaises(Article.DoesNotExist):
+            Article.objects.latest()
 
         a1 = Article.objects.create(
             headline="Article 1", pub_date=datetime(2005, 7, 26),
@@ -119,7 +121,8 @@ class EarliestOrLatestTests(TestCase):
         # "get_latest_by" set -- just pass in the field name manually.
         Person.objects.create(name="Ralph", birthday=datetime(1950, 1, 1))
         p2 = Person.objects.create(name="Stephanie", birthday=datetime(1960, 2, 3))
-        self.assertRaises(AssertionError, Person.objects.latest)
+        with self.assertRaises(AssertionError):
+            Person.objects.latest()
         self.assertEqual(Person.objects.latest("birthday"), p2)
 
 
@@ -164,9 +167,12 @@ class TestFirstLast(TestCase):
         def check():
             # We know that we've broken the __iter__ method, so the queryset
             # should always raise an exception.
-            self.assertRaises(IndexError, lambda: IndexErrorArticle.objects.all()[0])
-            self.assertRaises(IndexError, IndexErrorArticle.objects.all().first)
-            self.assertRaises(IndexError, IndexErrorArticle.objects.all().last)
+            with self.assertRaises(IndexError):
+                IndexErrorArticle.objects.all()[0]
+            with self.assertRaises(IndexError):
+                IndexErrorArticle.objects.all().first()
+            with self.assertRaises(IndexError):
+                IndexErrorArticle.objects.all().last()
 
         check()
 

tests/get_object_or_404/tests.py

@@ -13,7 +13,8 @@ class GetObjectOr404Tests(TestCase):
         a2 = Author.objects.create(name="Patsy")
 
         # No Articles yet, so we should get a Http404 error.
-        self.assertRaises(Http404, get_object_or_404, Article, title="Foo")
+        with self.assertRaises(Http404):
+            get_object_or_404(Article, title="Foo")
 
         article = Article.objects.create(title="Run away!")
         article.authors.set([a1, a2])
@@ -30,10 +31,8 @@ class GetObjectOr404Tests(TestCase):
         )
 
         # No articles containing "Camelot".  This should raise a Http404 error.
-        self.assertRaises(
-            Http404,
-            get_object_or_404, a1.article_set, title__contains="Camelot"
-        )
+        with self.assertRaises(Http404):
+            get_object_or_404(a1.article_set, title__contains="Camelot")
 
         # Custom managers can be used too.
         self.assertEqual(
@@ -50,16 +49,12 @@ class GetObjectOr404Tests(TestCase):
         # Just as when using a get() lookup, you will get an error if more than
         # one object is returned.
 
-        self.assertRaises(
-            Author.MultipleObjectsReturned,
-            get_object_or_404, Author.objects.all()
-        )
+        with self.assertRaises(Author.MultipleObjectsReturned):
+            get_object_or_404(Author.objects.all())
 
         # Using an empty QuerySet raises a Http404 error.
-        self.assertRaises(
-            Http404,
-            get_object_or_404, Article.objects.none(), title__contains="Run"
-        )
+        with self.assertRaises(Http404):
+            get_object_or_404(Article.objects.none(), title__contains="Run")
 
         # get_list_or_404 can be used to get lists of objects
         self.assertEqual(
@@ -68,10 +63,8 @@ class GetObjectOr404Tests(TestCase):
         )
 
         # Http404 is returned if the list is empty.
-        self.assertRaises(
-            Http404,
-            get_list_or_404, a1.article_set, title__icontains="Shrubbery"
-        )
+        with self.assertRaises(Http404):
+            get_list_or_404(a1.article_set, title__icontains="Shrubbery")
 
         # Custom managers can be used too.
         self.assertEqual(

tests/get_or_create/tests.py

@@ -62,10 +62,8 @@ class GetOrCreateTests(TestCase):
         If you don't specify a value or default value for all required
         fields, you will get an error.
         """
-        self.assertRaises(
-            IntegrityError,
-            Person.objects.get_or_create, first_name="Tom", last_name="Smith"
-        )
+        with self.assertRaises(IntegrityError):
+            Person.objects.get_or_create(first_name="Tom", last_name="Smith")
 
     def test_get_or_create_on_related_manager(self):
         p = Publisher.objects.create(name="Acme Publishing")
@@ -159,10 +157,8 @@ class GetOrCreateTestsWithManualPKs(TestCase):
         If you specify an existing primary key, but different other fields,
         then you will get an error and data will not be updated.
         """
-        self.assertRaises(
-            IntegrityError,
-            ManualPrimaryKeyTest.objects.get_or_create, id=1, data="Different"
-        )
+        with self.assertRaises(IntegrityError):
+            ManualPrimaryKeyTest.objects.get_or_create(id=1, data="Different")
         self.assertEqual(ManualPrimaryKeyTest.objects.get(id=1).data, "Original")
 
     def test_get_or_create_raises_IntegrityError_plus_traceback(self):
@@ -246,7 +242,8 @@ class GetOrCreateThroughManyToMany(TestCase):
     def test_something(self):
         Tag.objects.create(text='foo')
         a_thing = Thing.objects.create(name='a')
-        self.assertRaises(IntegrityError, a_thing.tags.get_or_create, text='foo')
+        with self.assertRaises(IntegrityError):
+            a_thing.tags.get_or_create(text='foo')
 
 
 class UpdateOrCreateTests(TestCase):
@@ -292,8 +289,8 @@ class UpdateOrCreateTests(TestCase):
         If you don't specify a value or default value for all required
         fields, you will get an error.
         """
-        self.assertRaises(IntegrityError,
-            Person.objects.update_or_create, first_name="Tom", last_name="Smith")
+        with self.assertRaises(IntegrityError):
+            Person.objects.update_or_create(first_name="Tom", last_name="Smith")
 
     def test_manual_primary_key_test(self):
         """
@@ -301,10 +298,8 @@ class UpdateOrCreateTests(TestCase):
         then you will get an error and data will not be updated.
         """
         ManualPrimaryKeyTest.objects.create(id=1, data="Original")
-        self.assertRaises(
-            IntegrityError,
-            ManualPrimaryKeyTest.objects.update_or_create, id=1, data="Different"
-        )
+        with self.assertRaises(IntegrityError):
+            ManualPrimaryKeyTest.objects.update_or_create(id=1, data="Different")
         self.assertEqual(ManualPrimaryKeyTest.objects.get(id=1).data, "Original")
 
     def test_error_contains_full_traceback(self):

tests/gis_tests/distapp/tests.py

@@ -95,7 +95,8 @@ class DistanceTest(TestCase):
             if type_error:
                 # A ValueError should be raised on PostGIS when trying to pass
                 # Distance objects into a DWithin query using a geodetic field.
-                self.assertRaises(ValueError, AustraliaCity.objects.filter(point__dwithin=(self.au_pnt, dist)).count)
+                with self.assertRaises(ValueError):
+                    AustraliaCity.objects.filter(point__dwithin=(self.au_pnt, dist)).count()
             else:
                 self.assertListEqual(au_cities, self.get_names(qs.filter(point__dwithin=(self.au_pnt, dist))))
 
@@ -289,11 +290,12 @@ class DistanceTest(TestCase):
 
         # Too many params (4 in this case) should raise a ValueError.
         queryset = AustraliaCity.objects.filter(point__distance_lte=('POINT(5 23)', D(km=100), 'spheroid', '4'))
-        self.assertRaises(ValueError, len, queryset)
+        with self.assertRaises(ValueError):
+            len(queryset)
 
         # Not enough params should raise a ValueError.
-        self.assertRaises(ValueError, len,
-                          AustraliaCity.objects.filter(point__distance_lte=('POINT(5 23)',)))
+        with self.assertRaises(ValueError):
+            len(AustraliaCity.objects.filter(point__distance_lte=('POINT(5 23)',)))
 
         # Getting all cities w/in 550 miles of Hobart.
         hobart = AustraliaCity.objects.get(name='Hobart')
@@ -382,7 +384,8 @@ class DistanceTest(TestCase):
             self.assertAlmostEqual(len_m1, qs[0].length.m, tol)
         else:
             # Does not support geodetic coordinate systems.
-            self.assertRaises(ValueError, Interstate.objects.length)
+            with self.assertRaises(ValueError):
+                Interstate.objects.length()
 
         # Now doing length on a projected coordinate system.
         i10 = SouthTexasInterstate.objects.length().get(name='I-10')

tests/gis_tests/gdal_tests/test_driver.py

@@ -40,7 +40,8 @@ class DriverTest(unittest.TestCase):
     def test02_invalid_driver(self):
         "Testing invalid GDAL/OGR Data Source Drivers."
         for i in invalid_drivers:
-            self.assertRaises(GDALException, Driver, i)
+            with self.assertRaises(GDALException):
+                Driver(i)
 
     def test03_aliases(self):
         "Testing driver aliases."

tests/gis_tests/gdal_tests/test_ds.py

@@ -87,7 +87,8 @@ class DataSourceTest(unittest.TestCase):
     def test02_invalid_shp(self):
         "Testing invalid SHP files for the Data Source."
         for source in bad_ds:
-            self.assertRaises(GDALException, DataSource, source.ds)
+            with self.assertRaises(GDALException):
+                DataSource(source.ds)
 
     def test03a_layers(self):
         "Testing Data Source Layers."
@@ -122,8 +123,10 @@ class DataSourceTest(unittest.TestCase):
                     self.assertIn(f, source.fields)
 
                 # Negative FIDs are not allowed.
-                self.assertRaises(OGRIndexError, layer.__getitem__, -1)
-                self.assertRaises(OGRIndexError, layer.__getitem__, 50000)
+                with self.assertRaises(OGRIndexError):
+                    layer.__getitem__(-1)
+                with self.assertRaises(OGRIndexError):
+                    layer.__getitem__(50000)
 
                 if hasattr(source, 'field_values'):
                     fld_names = source.field_values.keys()
@@ -233,11 +236,13 @@ class DataSourceTest(unittest.TestCase):
         self.assertIsNone(lyr.spatial_filter)
 
         # Must be set a/an OGRGeometry or 4-tuple.
-        self.assertRaises(TypeError, lyr._set_spatial_filter, 'foo')
+        with self.assertRaises(TypeError):
+            lyr._set_spatial_filter('foo')
 
         # Setting the spatial filter with a tuple/list with the extent of
         # a buffer centering around Pueblo.
-        self.assertRaises(ValueError, lyr._set_spatial_filter, list(range(5)))
+        with self.assertRaises(ValueError):
+            lyr._set_spatial_filter(list(range(5)))
         filter_extent = (-105.609252, 37.255001, -103.609252, 39.255001)
         lyr.spatial_filter = (-105.609252, 37.255001, -103.609252, 39.255001)
         self.assertEqual(OGRGeometry.from_bbox(filter_extent), lyr.spatial_filter)

tests/gis_tests/gdal_tests/test_envelope.py

@@ -25,13 +25,20 @@ class EnvelopeTest(unittest.TestCase):
         Envelope(0, 0, 5, 5)
         Envelope(0, '0', '5', 5)  # Thanks to ww for this
         Envelope(e1._envelope)
-        self.assertRaises(GDALException, Envelope, (5, 5, 0, 0))
-        self.assertRaises(GDALException, Envelope, 5, 5, 0, 0)
-        self.assertRaises(GDALException, Envelope, (0, 0, 5, 5, 3))
-        self.assertRaises(GDALException, Envelope, ())
-        self.assertRaises(ValueError, Envelope, 0, 'a', 5, 5)
-        self.assertRaises(TypeError, Envelope, 'foo')
-        self.assertRaises(GDALException, Envelope, (1, 1, 0, 0))
+        with self.assertRaises(GDALException):
+            Envelope((5, 5, 0, 0))
+        with self.assertRaises(GDALException):
+            Envelope(5, 5, 0, 0)
+        with self.assertRaises(GDALException):
+            Envelope((0, 0, 5, 5, 3))
+        with self.assertRaises(GDALException):
+            Envelope(())
+        with self.assertRaises(ValueError):
+            Envelope(0, 'a', 5, 5)
+        with self.assertRaises(TypeError):
+            Envelope('foo')
+        with self.assertRaises(GDALException):
+            Envelope((1, 1, 0, 0))
         try:
             Envelope(0, 0, 0, 0)
         except GDALException:

tests/gis_tests/gdal_tests/test_geom.py

@@ -36,9 +36,12 @@ class OGRGeomTest(unittest.TestCase, TestDataMixin):
         OGRGeomType('Unknown')
 
         # Should throw TypeError on this input
-        self.assertRaises(GDALException, OGRGeomType, 23)
-        self.assertRaises(GDALException, OGRGeomType, 'fooD')
-        self.assertRaises(GDALException, OGRGeomType, 9)
+        with self.assertRaises(GDALException):
+            OGRGeomType(23)
+        with self.assertRaises(GDALException):
+            OGRGeomType('fooD')
+        with self.assertRaises(GDALException):
+            OGRGeomType(9)
 
         # Equivalence can take strings, ints, and other OGRGeomTypes
         self.assertEqual(OGRGeomType(1), OGRGeomType(1))
@@ -168,7 +171,8 @@ class OGRGeomTest(unittest.TestCase, TestDataMixin):
             self.assertEqual(ls.coords, linestr.tuple)
             self.assertEqual(linestr, OGRGeometry(ls.wkt))
             self.assertNotEqual(linestr, prev)
-            self.assertRaises(OGRIndexError, linestr.__getitem__, len(linestr))
+            with self.assertRaises(OGRIndexError):
+                linestr.__getitem__(len(linestr))
             prev = linestr
 
             # Testing the x, y properties.
@@ -192,7 +196,8 @@ class OGRGeomTest(unittest.TestCase, TestDataMixin):
             for ls in mlinestr:
                 self.assertEqual(2, ls.geom_type)
                 self.assertEqual('LINESTRING', ls.geom_name)
-            self.assertRaises(OGRIndexError, mlinestr.__getitem__, len(mlinestr))
+            with self.assertRaises(OGRIndexError):
+                mlinestr.__getitem__(len(mlinestr))
 
     def test_linearring(self):
         "Testing LinearRing objects."
@@ -263,7 +268,8 @@ class OGRGeomTest(unittest.TestCase, TestDataMixin):
             if mp.valid:
                 self.assertEqual(mp.n_p, mpoly.point_count)
                 self.assertEqual(mp.num_geom, len(mpoly))
-                self.assertRaises(OGRIndexError, mpoly.__getitem__, len(mpoly))
+                with self.assertRaises(OGRIndexError):
+                    mpoly.__getitem__(len(mpoly))
                 for p in mpoly:
                     self.assertEqual('POLYGON', p.geom_name)
                     self.assertEqual(3, p.geom_type)
@@ -415,7 +421,8 @@ class OGRGeomTest(unittest.TestCase, TestDataMixin):
         # Can't insert a Point into a MultiPolygon.
         mp = OGRGeometry('MultiPolygon')
         pnt = OGRGeometry('POINT(5 23)')
-        self.assertRaises(GDALException, mp.add, pnt)
+        with self.assertRaises(GDALException):
+            mp.add(pnt)
 
         # GeometryCollection.add may take an OGRGeometry (if another collection
         # of the same type all child geoms will be added individually) or WKT.

tests/gis_tests/gdal_tests/test_raster.py

@@ -350,7 +350,8 @@ class GDALBandTests(unittest.TestCase):
         band = rs.bands[0]
 
         # Setting attributes in write mode raises exception in the _flush method
-        self.assertRaises(GDALException, setattr, band, 'nodata_value', 10)
+        with self.assertRaises(GDALException):
+            setattr(band, 'nodata_value', 10)
 
     def test_band_data_setters(self):
         # Create in-memory raster and get band

tests/gis_tests/gdal_tests/test_srs.py

@@ -249,8 +249,10 @@ class SpatialRefTest(unittest.TestCase):
     def test13_attr_value(self):
         "Testing the attr_value() method."
         s1 = SpatialReference('WGS84')
-        self.assertRaises(TypeError, s1.__getitem__, 0)
-        self.assertRaises(TypeError, s1.__getitem__, ('GEOGCS', 'foo'))
+        with self.assertRaises(TypeError):
+            s1.__getitem__(0)
+        with self.assertRaises(TypeError):
+            s1.__getitem__(('GEOGCS', 'foo'))
         self.assertEqual('WGS 84', s1['GEOGCS'])
         self.assertEqual('WGS_1984', s1['DATUM'])
         self.assertEqual('EPSG', s1['AUTHORITY'])

tests/gis_tests/geo3d/tests.py

@@ -157,8 +157,8 @@ class Geo3DTest(Geo3DLoadingHelper, TestCase):
 
         # The city shapefile is 2D, and won't be able to fill the coordinates
         # in the 3D model -- thus, a LayerMapError is raised.
-        self.assertRaises(LayerMapError, LayerMapping,
-                          Point3D, city_file, point_mapping, transform=False)
+        with self.assertRaises(LayerMapError):
+            LayerMapping(Point3D, city_file, point_mapping, transform=False)
 
         # 3D model should take 3D data just fine.
         lm = LayerMapping(Point3D, vrt_file, point_mapping, transform=False)

tests/gis_tests/geoapp/test_feeds.py

@@ -86,5 +86,7 @@ class GeoFeedTest(TestCase):
             self.assertChildNodes(item, ['title', 'link', 'description', 'guid', 'geo:lat', 'geo:lon'])
 
         # Boxes and Polygons aren't allowed in W3C Geo feeds.
-        self.assertRaises(ValueError, self.client.get, '/feeds/w3cgeo2/')  # Box in <channel>
-        self.assertRaises(ValueError, self.client.get, '/feeds/w3cgeo3/')  # Polygons in <entry>
+        with self.assertRaises(ValueError):  # Box in <channel>
+            self.client.get('/feeds/w3cgeo2/')
+        with self.assertRaises(ValueError):  # Polygons in <entry>
+            self.client.get('/feeds/w3cgeo3/')

tests/gis_tests/geoapp/tests.py

@@ -408,13 +408,15 @@ class GeoLookupTest(TestCase):
 
         # Not passing in a geometry as first param should
         # raise a type error when initializing the GeoQuerySet
-        self.assertRaises(ValueError, Country.objects.filter, mpoly__relate=(23, 'foo'))
+        with self.assertRaises(ValueError):
+            Country.objects.filter(mpoly__relate=(23, 'foo'))
 
         # Making sure the right exception is raised for the given
         # bad arguments.
         for bad_args, e in [((pnt1, 0), ValueError), ((pnt2, 'T*T***FF*', 0), ValueError)]:
             qs = Country.objects.filter(mpoly__relate=bad_args)
-            self.assertRaises(e, qs.count)
+            with self.assertRaises(e):
+                qs.count()
 
         # Relate works differently for the different backends.
         if postgis or spatialite:
@@ -556,7 +558,8 @@ class GeoQuerySetTest(TestCase):
         "Testing GeoJSON output from the database using GeoQuerySet.geojson()."
         # Only PostGIS and SpatiaLite support GeoJSON.
         if not connection.ops.geojson:
-            self.assertRaises(NotImplementedError, Country.objects.all().geojson, field_name='mpoly')
+            with self.assertRaises(NotImplementedError):
+                Country.objects.all().geojson(field_name='mpoly')
             return
 
         pueblo_json = '{"type":"Point","coordinates":[-104.609252,38.255001]}'
@@ -579,7 +582,8 @@ class GeoQuerySetTest(TestCase):
             )
 
         # Precision argument should only be an integer
-        self.assertRaises(TypeError, City.objects.geojson, precision='foo')
+        with self.assertRaises(TypeError):
+            City.objects.geojson(precision='foo')
 
         # Reference queries and values.
         # SELECT ST_AsGeoJson("geoapp_city"."point", 8, 0)
@@ -610,7 +614,8 @@ class GeoQuerySetTest(TestCase):
         # Should throw a TypeError when trying to obtain GML from a
         # non-geometry field.
         qs = City.objects.all()
-        self.assertRaises(TypeError, qs.gml, field_name='name')
+        with self.assertRaises(TypeError):
+            qs.gml(field_name='name')
         ptown1 = City.objects.gml(field_name='point', precision=9).get(name='Pueblo')
         ptown2 = City.objects.gml(precision=9).get(name='Pueblo')
 
@@ -639,7 +644,8 @@ class GeoQuerySetTest(TestCase):
         # Should throw a TypeError when trying to obtain KML from a
         #  non-geometry field.
         qs = City.objects.all()
-        self.assertRaises(TypeError, qs.kml, 'name')
+        with self.assertRaises(TypeError):
+            qs.kml('name')
 
         # Ensuring the KML is as expected.
         ptown1 = City.objects.kml(field_name='point', precision=9).get(name='Pueblo')
@@ -652,10 +658,8 @@ class GeoQuerySetTest(TestCase):
         Testing the `MakeLine` aggregate.
         """
         if not connection.features.supports_make_line_aggr:
-            self.assertRaises(
-                NotImplementedError,
-                City.objects.all().aggregate, MakeLine('point')
-            )
+            with self.assertRaises(NotImplementedError):
+                City.objects.all().aggregate(MakeLine('point'))
             return
 
         # MakeLine on an inappropriate field returns simply None
@@ -734,7 +738,8 @@ class GeoQuerySetTest(TestCase):
         coords.reverse()
         self.assertEqual(tuple(coords), t.reverse_geom.coords)
         if oracle:
-            self.assertRaises(TypeError, State.objects.reverse_geom)
+            with self.assertRaises(TypeError):
+                State.objects.reverse_geom()
 
     @skipUnlessDBFeature("has_scale_method")
     def test_scale(self):
@@ -754,9 +759,11 @@ class GeoQuerySetTest(TestCase):
         "Testing GeoQuerySet.snap_to_grid()."
         # Let's try and break snap_to_grid() with bad combinations of arguments.
         for bad_args in ((), range(3), range(5)):
-            self.assertRaises(ValueError, Country.objects.snap_to_grid, *bad_args)
+            with self.assertRaises(ValueError):
+                Country.objects.snap_to_grid(*bad_args)
         for bad_args in (('1.0',), (1.0, None), tuple(map(six.text_type, range(4)))):
-            self.assertRaises(TypeError, Country.objects.snap_to_grid, *bad_args)
+            with self.assertRaises(TypeError):
+                Country.objects.snap_to_grid(*bad_args)
 
         # Boundary for San Marino, courtesy of Bjorn Sandvik of thematicmapping.org
         # from the world borders dataset he provides.
@@ -802,7 +809,8 @@ class GeoQuerySetTest(TestCase):
     def test_svg(self):
         "Testing SVG output using GeoQuerySet.svg()."
 
-        self.assertRaises(TypeError, City.objects.svg, precision='foo')
+        with self.assertRaises(TypeError):
+            City.objects.svg(precision='foo')
         # SELECT AsSVG(geoapp_city.point, 0, 8) FROM geoapp_city WHERE name = 'Pueblo';
         svg1 = 'cx="-104.609252" cy="-38.255001"'
         # Even though relative, only one point so it's practically the same except for
@@ -861,7 +869,8 @@ class GeoQuerySetTest(TestCase):
         union1 = fromstr('MULTIPOINT(-96.801611 32.782057,-95.363151 29.763374)')
         union2 = fromstr('MULTIPOINT(-95.363151 29.763374,-96.801611 32.782057)')
         qs = City.objects.filter(point__within=tx)
-        self.assertRaises(ValueError, qs.aggregate, Union('name'))
+        with self.assertRaises(ValueError):
+            qs.aggregate(Union('name'))
         # Using `field_name` keyword argument in one query and specifying an
         # order in the other (which should not be used because this is
         # an aggregate method on a spatial column)

tests/gis_tests/geogapp/tests.py

@@ -56,13 +56,16 @@ class GeographyTest(TestCase):
         # http://postgis.refractions.net/documentation/manual-1.5/ch08.html#PostGIS_GeographyFunctions
         z = Zipcode.objects.get(code='77002')
         # ST_Within not available.
-        self.assertRaises(ValueError, City.objects.filter(point__within=z.poly).count)
+        with self.assertRaises(ValueError):
+            City.objects.filter(point__within=z.poly).count()
         # `@` operator not available.
-        self.assertRaises(ValueError, City.objects.filter(point__contained=z.poly).count)
+        with self.assertRaises(ValueError):
+            City.objects.filter(point__contained=z.poly).count()
 
         # Regression test for #14060, `~=` was never really implemented for PostGIS.
         htown = City.objects.get(name='Houston')
-        self.assertRaises(ValueError, City.objects.get, point__exact=htown.point)
+        with self.assertRaises(ValueError):
+            City.objects.get(point__exact=htown.point)
 
     @skipUnless(HAS_GDAL, "GDAL is required.")
     def test05_geography_layermapping(self):

tests/gis_tests/geos_tests/test_geos.py

@@ -62,7 +62,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
         # a C method is given a NULL memory reference.
         for fg in (fg1, fg2):
             # Equivalent to `fg.ptr`
-            self.assertRaises(GEOSException, fg._get_ptr)
+            with self.assertRaises(GEOSException):
+                fg._get_ptr()
 
         # Anything that is either not None or the acceptable pointer type will
         # result in a TypeError when trying to assign it to the `ptr` property.
@@ -71,8 +72,10 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
         bad_ptrs = (5, ctypes.c_char_p(b'foobar'))
         for bad_ptr in bad_ptrs:
             # Equivalent to `fg.ptr = bad_ptr`
-            self.assertRaises(TypeError, fg1._set_ptr, bad_ptr)
-            self.assertRaises(TypeError, fg2._set_ptr, bad_ptr)
+            with self.assertRaises(TypeError):
+                fg1._set_ptr(bad_ptr)
+            with self.assertRaises(TypeError):
+                fg2._set_ptr(bad_ptr)
 
     def test_wkt(self):
         "Testing WKT output."
@@ -134,15 +137,18 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
                 fromstr(err.wkt)
 
         # Bad WKB
-        self.assertRaises(GEOSException, GEOSGeometry, six.memoryview(b'0'))
+        with self.assertRaises(GEOSException):
+            GEOSGeometry(six.memoryview(b'0'))
 
         class NotAGeometry(object):
             pass
 
         # Some other object
-        self.assertRaises(TypeError, GEOSGeometry, NotAGeometry())
+        with self.assertRaises(TypeError):
+            GEOSGeometry(NotAGeometry())
         # None
-        self.assertRaises(TypeError, GEOSGeometry, None)
+        with self.assertRaises(TypeError):
+            GEOSGeometry(None)
 
     def test_wkb(self):
         "Testing WKB output."
@@ -288,7 +294,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
             self.assertAlmostEqual(mp.centroid[0], mpnt.centroid.tuple[0], 9)
             self.assertAlmostEqual(mp.centroid[1], mpnt.centroid.tuple[1], 9)
 
-            self.assertRaises(IndexError, mpnt.__getitem__, len(mpnt))
+            with self.assertRaises(IndexError):
+                mpnt.__getitem__(len(mpnt))
             self.assertEqual(mp.centroid, mpnt.centroid.tuple)
             self.assertEqual(mp.coords, tuple(m.tuple for m in mpnt))
             for p in mpnt:
@@ -314,7 +321,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
 
             self.assertEqual(ls, fromstr(l.wkt))
             self.assertEqual(False, ls == prev)  # Use assertEqual to test __eq__
-            self.assertRaises(IndexError, ls.__getitem__, len(ls))
+            with self.assertRaises(IndexError):
+                ls.__getitem__(len(ls))
             prev = ls
 
             # Creating a LineString from a tuple, list, and numpy array
@@ -361,7 +369,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
                 self.assertEqual(ls.geom_typeid, 1)
                 self.assertEqual(ls.empty, False)
 
-            self.assertRaises(IndexError, ml.__getitem__, len(ml))
+            with self.assertRaises(IndexError):
+                ml.__getitem__(len(ml))
             self.assertEqual(ml.wkt, MultiLineString(*tuple(s.clone() for s in ml)).wkt)
             self.assertEqual(ml, MultiLineString(*tuple(LineString(s.tuple) for s in ml)))
 
@@ -442,9 +451,12 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
                 self.assertEqual(p.ext_ring_cs, poly[0].tuple)  # Testing __getitem__
 
             # Testing __getitem__ and __setitem__ on invalid indices
-            self.assertRaises(IndexError, poly.__getitem__, len(poly))
-            self.assertRaises(IndexError, poly.__setitem__, len(poly), False)
-            self.assertRaises(IndexError, poly.__getitem__, -1 * len(poly) - 1)
+            with self.assertRaises(IndexError):
+                poly.__getitem__(len(poly))
+            with self.assertRaises(IndexError):
+                poly.__setitem__(len(poly), False)
+            with self.assertRaises(IndexError):
+                poly.__getitem__(-1 * len(poly) - 1)
 
             # Testing __iter__
             for r in poly:
@@ -452,8 +464,10 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
                 self.assertEqual(r.geom_typeid, 2)
 
             # Testing polygon construction.
-            self.assertRaises(TypeError, Polygon, 0, [1, 2, 3])
-            self.assertRaises(TypeError, Polygon, 'foo')
+            with self.assertRaises(TypeError):
+                Polygon(0, [1, 2, 3])
+            with self.assertRaises(TypeError):
+                Polygon('foo')
 
             # Polygon(shell, (hole1, ... holeN))
             rings = tuple(r for r in poly)
@@ -500,7 +514,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
                 self.assertEqual(mp.num_geom, mpoly.num_geom)
                 self.assertEqual(mp.n_p, mpoly.num_coords)
                 self.assertEqual(mp.num_geom, len(mpoly))
-                self.assertRaises(IndexError, mpoly.__getitem__, len(mpoly))
+                with self.assertRaises(IndexError):
+                    mpoly.__getitem__(len(mpoly))
                 for p in mpoly:
                     self.assertEqual(p.geom_type, 'Polygon')
                     self.assertEqual(p.geom_typeid, 3)
@@ -563,7 +578,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
     def test_relate_pattern(self):
         "Testing relate() and relate_pattern()."
         g = fromstr('POINT (0 0)')
-        self.assertRaises(GEOSException, g.relate_pattern, 0, 'invalid pattern, yo')
+        with self.assertRaises(GEOSException):
+            g.relate_pattern(0, 'invalid pattern, yo')
         for rg in self.geometries.relate_geoms:
             a = fromstr(rg.wkt_a)
             b = fromstr(rg.wkt_b)
@@ -639,7 +655,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
             width = bg.width
 
             # Can't use a floating-point for the number of quadsegs.
-            self.assertRaises(ctypes.ArgumentError, g.buffer, width, float(quadsegs))
+            with self.assertRaises(ctypes.ArgumentError):
+                g.buffer(width, float(quadsegs))
 
             # Constructing our buffer
             buf = g.buffer(width, quadsegs)
@@ -743,7 +760,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
             poly = fromstr(p.wkt)
 
             # Should only be able to use __setitem__ with LinearRing geometries.
-            self.assertRaises(TypeError, poly.__setitem__, 0, LineString((1, 1), (2, 2)))
+            with self.assertRaises(TypeError):
+                poly.__setitem__(0, LineString((1, 1), (2, 2)))
 
             # Constructing the new shell by adding 500 to every point in the old shell.
             shell_tup = poly.shell.tuple
@@ -875,7 +893,8 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
         # Testing a 3D LineString
         ls = LineString((2., 3., 8.), (50., 250., -117.))
         self.assertEqual(((2., 3., 8.), (50., 250., -117.)), ls.tuple)
-        self.assertRaises(TypeError, ls.__setitem__, 0, (1., 2.))
+        with self.assertRaises(TypeError):
+            ls.__setitem__(0, (1., 2.))
         ls[0] = (1., 2., 3.)
         self.assertEqual((1., 2., 3.), ls[0])
 
@@ -961,9 +980,11 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
                 self.assertEqual('LINEARRING EMPTY', lr.wkt)
                 self.assertEqual(0, len(lr))
                 self.assertEqual(True, lr.empty)
-                self.assertRaises(IndexError, lr.__getitem__, 0)
+                with self.assertRaises(IndexError):
+                    lr.__getitem__(0)
             else:
-                self.assertRaises(IndexError, g.__getitem__, 0)
+                with self.assertRaises(IndexError):
+                    g.__getitem__(0)
 
     def test_collection_dims(self):
         gc = GeometryCollection([])
@@ -1089,25 +1110,31 @@ class GEOSTest(SimpleTestCase, TestDataMixin):
         """ Testing `transform` method (no SRID or negative SRID) """
 
         g = GEOSGeometry('POINT (-104.609 38.255)', srid=None)
-        self.assertRaises(GEOSException, g.transform, 2774)
+        with self.assertRaises(GEOSException):
+            g.transform(2774)
 
         g = GEOSGeometry('POINT (-104.609 38.255)', srid=None)
-        self.assertRaises(GEOSException, g.transform, 2774, clone=True)
+        with self.assertRaises(GEOSException):
+            g.transform(2774, clone=True)
 
         g = GEOSGeometry('POINT (-104.609 38.255)', srid=-1)
-        self.assertRaises(GEOSException, g.transform, 2774)
+        with self.assertRaises(GEOSException):
+            g.transform(2774)
 
         g = GEOSGeometry('POINT (-104.609 38.255)', srid=-1)
-        self.assertRaises(GEOSException, g.transform, 2774, clone=True)
+        with self.assertRaises(GEOSException):
+            g.transform(2774, clone=True)
 
     @mock.patch('django.contrib.gis.gdal.HAS_GDAL', False)
     def test_transform_nogdal(self):
         """ Testing `transform` method (GDAL not available) """
         g = GEOSGeometry('POINT (-104.609 38.255)', 4326)
-        self.assertRaises(GEOSException, g.transform, 2774)
+        with self.assertRaises(GEOSException):
+            g.transform(2774)
 
         g = GEOSGeometry('POINT (-104.609 38.255)', 4326)
-        self.assertRaises(GEOSException, g.transform, 2774, clone=True)
+        with self.assertRaises(GEOSException):
+            g.transform(2774, clone=True)
 
     def test_extent(self):
         "Testing `extent` method."

tests/gis_tests/geos_tests/test_geos_mutation.py

@@ -82,8 +82,10 @@ class GEOSMutationTest(unittest.TestCase):
         p = Point(1, 2)
         for i in range(-2, 2):
             p._checkindex(i)
-        self.assertRaises(IndexError, p._checkindex, 2)
-        self.assertRaises(IndexError, p._checkindex, -3)
+        with self.assertRaises(IndexError):
+            p._checkindex(2)
+        with self.assertRaises(IndexError):
+            p._checkindex(-3)
 
     def test01_PointMutations(self):
         'Testing Point mutations'
@@ -100,8 +102,10 @@ class GEOSMutationTest(unittest.TestCase):
 
     def test02_PointExceptions(self):
         'Testing Point exceptions'
-        self.assertRaises(TypeError, Point, range(1))
-        self.assertRaises(TypeError, Point, range(4))
+        with self.assertRaises(TypeError):
+            Point(range(1))
+        with self.assertRaises(TypeError):
+            Point(range(4))
 
     def test03_PointApi(self):
         'Testing Point API'

tests/gis_tests/geos_tests/test_io.py

@@ -27,13 +27,16 @@ class GEOSIOTest(SimpleTestCase):
             self.assertEqual(ref, geom)
 
         # Should only accept six.string_types objects.
-        self.assertRaises(TypeError, wkt_r.read, 1)
-        self.assertRaises(TypeError, wkt_r.read, memoryview(b'foo'))
+        with self.assertRaises(TypeError):
+            wkt_r.read(1)
+        with self.assertRaises(TypeError):
+            wkt_r.read(memoryview(b'foo'))
 
     def test02_wktwriter(self):
         # Creating a WKTWriter instance, testing its ptr property.
         wkt_w = WKTWriter()
-        self.assertRaises(TypeError, wkt_w._set_ptr, WKTReader.ptr_type())
+        with self.assertRaises(TypeError):
+            wkt_w._set_ptr(WKTReader.ptr_type())
 
         ref = GEOSGeometry('POINT (5 23)')
         ref_wkt = 'POINT (5.0000000000000000 23.0000000000000000)'
@@ -56,7 +59,8 @@ class GEOSIOTest(SimpleTestCase):
 
         bad_input = (1, 5.23, None, False)
         for bad_wkb in bad_input:
-            self.assertRaises(TypeError, wkb_r.read, bad_wkb)
+            with self.assertRaises(TypeError):
+                wkb_r.read(bad_wkb)
 
     def test04_wkbwriter(self):
         wkb_w = WKBWriter()
@@ -75,7 +79,8 @@ class GEOSIOTest(SimpleTestCase):
         # Ensuring bad byteorders are not accepted.
         for bad_byteorder in (-1, 2, 523, 'foo', None):
             # Equivalent of `wkb_w.byteorder = bad_byteorder`
-            self.assertRaises(ValueError, wkb_w._set_byteorder, bad_byteorder)
+            with self.assertRaises(ValueError):
+                wkb_w._set_byteorder(bad_byteorder)
 
         # Setting the byteorder to 0 (for Big Endian)
         wkb_w.byteorder = 0
@@ -97,7 +102,8 @@ class GEOSIOTest(SimpleTestCase):
         # Ensuring bad output dimensions are not accepted
         for bad_outdim in (-1, 0, 1, 4, 423, 'foo', None):
             # Equivalent of `wkb_w.outdim = bad_outdim`
-            self.assertRaises(ValueError, wkb_w._set_outdim, bad_outdim)
+            with self.assertRaises(ValueError):
+                wkb_w._set_outdim(bad_outdim)
 
         # Now setting the output dimensions to be 3
         wkb_w.outdim = 3

tests/gis_tests/geos_tests/test_mutable_list.py

@@ -128,9 +128,11 @@ class ListMixinTest(unittest.TestCase):
                         self.assertEqual(pl, ul[:], 'set slice [%d:%d:%d]' % (i, j, k))
 
                         sliceLen = len(ul[i:j:k])
-                        self.assertRaises(ValueError, setfcn, ul, i, j, k, sliceLen + 1)
+                        with self.assertRaises(ValueError):
+                            setfcn(ul, i, j, k, sliceLen + 1)
                         if sliceLen > 2:
-                            self.assertRaises(ValueError, setfcn, ul, i, j, k, sliceLen - 1)
+                            with self.assertRaises(ValueError):
+                                setfcn(ul, i, j, k, sliceLen - 1)
 
                 for k in self.step_range():
                     ssl = nextRange(len(ul[i::k]))
@@ -223,9 +225,12 @@ class ListMixinTest(unittest.TestCase):
             del x[i]
         pl, ul = self.lists_of_len()
         for i in (-1 - self.limit, self.limit):
-            self.assertRaises(IndexError, setfcn, ul, i)  # 'set index %d' % i)
-            self.assertRaises(IndexError, getfcn, ul, i)  # 'get index %d' % i)
-            self.assertRaises(IndexError, delfcn, ul, i)  # 'del index %d' % i)
+            with self.assertRaises(IndexError):  # 'set index %d' % i)
+                setfcn(ul, i)
+            with self.assertRaises(IndexError):  # 'get index %d' % i)
+                getfcn(ul, i)
+            with self.assertRaises(IndexError):  # 'del index %d' % i)
+                delfcn(ul, i)
 
     def test06_list_methods(self):
         'List methods'
@@ -261,8 +266,10 @@ class ListMixinTest(unittest.TestCase):
 
         def popfcn(x, i):
             x.pop(i)
-        self.assertRaises(IndexError, popfcn, ul, self.limit)
-        self.assertRaises(IndexError, popfcn, ul, -1 - self.limit)
+        with self.assertRaises(IndexError):
+            popfcn(ul, self.limit)
+        with self.assertRaises(IndexError):
+            popfcn(ul, -1 - self.limit)
 
         pl, ul = self.lists_of_len()
         for val in range(self.limit):
@@ -282,8 +289,10 @@ class ListMixinTest(unittest.TestCase):
 
         def removefcn(x, v):
             return x.remove(v)
-        self.assertRaises(ValueError, indexfcn, ul, 40)
-        self.assertRaises(ValueError, removefcn, ul, 40)
+        with self.assertRaises(ValueError):
+            indexfcn(ul, 40)
+        with self.assertRaises(ValueError):
+            removefcn(ul, 40)
 
     def test07_allowed_types(self):
         'Type-restricted list'
@@ -294,8 +303,10 @@ class ListMixinTest(unittest.TestCase):
 
         def setfcn(x, i, v):
             x[i] = v
-        self.assertRaises(TypeError, setfcn, ul, 2, 'hello')
-        self.assertRaises(TypeError, setfcn, ul, slice(0, 3, 2), ('hello', 'goodbye'))
+        with self.assertRaises(TypeError):
+            setfcn(ul, 2, 'hello')
+        with self.assertRaises(TypeError):
+            setfcn(ul, slice(0, 3, 2), ('hello', 'goodbye'))
 
     def test08_min_length(self):
         'Length limits'
@@ -308,14 +319,17 @@ class ListMixinTest(unittest.TestCase):
         def setfcn(x, i):
             x[:i] = []
         for i in range(len(ul) - ul._minlength + 1, len(ul)):
-            self.assertRaises(ValueError, delfcn, ul, i)
-            self.assertRaises(ValueError, setfcn, ul, i)
+            with self.assertRaises(ValueError):
+                delfcn(ul, i)
+            with self.assertRaises(ValueError):
+                setfcn(ul, i)
         del ul[:len(ul) - ul._minlength]
 
         ul._maxlength = 4
         for i in range(0, ul._maxlength - len(ul)):
             ul.append(i)
-        self.assertRaises(ValueError, ul.append, 10)
+        with self.assertRaises(ValueError):
+            ul.append(10)
 
     def test09_iterable_check(self):
         'Error on assigning non-iterable to slice'
@@ -323,7 +337,8 @@ class ListMixinTest(unittest.TestCase):
 
         def setfcn(x, i, v):
             x[i] = v
-        self.assertRaises(TypeError, setfcn, ul, slice(0, 3, 2), 2)
+        with self.assertRaises(TypeError):
+            setfcn(ul, slice(0, 3, 2), 2)
 
     def test10_checkindex(self):
         'Index check'
@@ -335,7 +350,8 @@ class ListMixinTest(unittest.TestCase):
                 self.assertEqual(ul._checkindex(i), i, '_checkindex(pos index)')
 
         for i in (-self.limit - 1, self.limit):
-            self.assertRaises(IndexError, ul._checkindex, i)
+            with self.assertRaises(IndexError):
+                ul._checkindex(i)
 
     def test_11_sorting(self):
         'Sorting'

tests/gis_tests/layermap/tests.py

@@ -156,11 +156,13 @@ class LayerMapTest(TestCase):
 
         # Testing invalid params for the `unique` keyword.
         for e, arg in ((TypeError, 5.0), (ValueError, 'foobar'), (ValueError, ('name', 'mpolygon'))):
-            self.assertRaises(e, LayerMapping, County, co_shp, co_mapping, transform=False, unique=arg)
+            with self.assertRaises(e):
+                LayerMapping(County, co_shp, co_mapping, transform=False, unique=arg)
 
         # No source reference system defined in the shapefile, should raise an error.
         if connection.features.supports_transform:
-            self.assertRaises(LayerMapError, LayerMapping, County, co_shp, co_mapping)
+            with self.assertRaises(LayerMapError):
+                LayerMapping(County, co_shp, co_mapping)
 
         # Passing in invalid ForeignKey mapping parameters -- must be a dictionary
         # mapping for the model the ForeignKey points to.
@@ -168,14 +170,17 @@ class LayerMapTest(TestCase):
         bad_fk_map1['state'] = 'name'
         bad_fk_map2 = copy(co_mapping)
         bad_fk_map2['state'] = {'nombre': 'State'}
-        self.assertRaises(TypeError, LayerMapping, County, co_shp, bad_fk_map1, transform=False)
-        self.assertRaises(LayerMapError, LayerMapping, County, co_shp, bad_fk_map2, transform=False)
+        with self.assertRaises(TypeError):
+            LayerMapping(County, co_shp, bad_fk_map1, transform=False)
+        with self.assertRaises(LayerMapError):
+            LayerMapping(County, co_shp, bad_fk_map2, transform=False)
 
         # There exist no State models for the ForeignKey mapping to work -- should raise
         # a MissingForeignKey exception (this error would be ignored if the `strict`
         # keyword is not set).
         lm = LayerMapping(County, co_shp, co_mapping, transform=False, unique='name')
-        self.assertRaises(MissingForeignKey, lm.save, silent=True, strict=True)
+        with self.assertRaises(MissingForeignKey):
+            lm.save(silent=True, strict=True)
 
         # Now creating the state models so the ForeignKey mapping may work.
         State.objects.bulk_create([
@@ -222,11 +227,13 @@ class LayerMapTest(TestCase):
         # Bad feature id ranges should raise a type error.
         bad_ranges = (5.0, 'foo', co_shp)
         for bad in bad_ranges:
-            self.assertRaises(TypeError, lm.save, fid_range=bad)
+            with self.assertRaises(TypeError):
+                lm.save(fid_range=bad)
 
         # Step keyword should not be allowed w/`fid_range`.
         fr = (3, 5)  # layer[3:5]
-        self.assertRaises(LayerMapError, lm.save, fid_range=fr, step=10)
+        with self.assertRaises(LayerMapError):
+            lm.save(fid_range=fr, step=10)
         lm.save(fid_range=fr)
 
         # Features IDs 3 & 4 are for Galveston County, Texas -- only

tests/gis_tests/test_geoforms.py

@@ -17,7 +17,8 @@ class GeometryFieldTest(SimpleTestCase):
         "Testing GeometryField initialization with defaults."
         fld = forms.GeometryField()
         for bad_default in ('blah', 3, 'FoO', None, 0):
-            self.assertRaises(ValidationError, fld.clean, bad_default)
+            with self.assertRaises(ValidationError):
+                fld.clean(bad_default)
 
     def test_srid(self):
         "Testing GeometryField with a SRID set."
@@ -59,7 +60,8 @@ class GeometryFieldTest(SimpleTestCase):
         # a WKT for any other geom_type will be properly transformed by `to_python`
         self.assertEqual(GEOSGeometry('LINESTRING(0 0, 1 1)'), pnt_fld.to_python('LINESTRING(0 0, 1 1)'))
         # but rejected by `clean`
-        self.assertRaises(forms.ValidationError, pnt_fld.clean, 'LINESTRING(0 0, 1 1)')
+        with self.assertRaises(forms.ValidationError):
+            pnt_fld.clean('LINESTRING(0 0, 1 1)')
 
     def test_to_python(self):
         """
@@ -72,7 +74,8 @@ class GeometryFieldTest(SimpleTestCase):
             self.assertEqual(GEOSGeometry(wkt), fld.to_python(wkt))
         # but raises a ValidationError for any other string
         for wkt in ('POINT(5)', 'MULTI   POLYGON(((0 0, 0 1, 1 1, 1 0, 0 0)))', 'BLAH(0 0, 1 1)'):
-            self.assertRaises(forms.ValidationError, fld.to_python, wkt)
+            with self.assertRaises(forms.ValidationError):
+                fld.to_python(wkt)
 
     def test_field_with_text_widget(self):
         class PointForm(forms.Form):

tests/gis_tests/test_geoip.py

@@ -66,23 +66,29 @@ class GeoIPTest(unittest.TestCase):
         # Improper parameters.
         bad_params = (23, 'foo', 15.23)
         for bad in bad_params:
-            self.assertRaises(GeoIPException, GeoIP, cache=bad)
+            with self.assertRaises(GeoIPException):
+                GeoIP(cache=bad)
             if isinstance(bad, six.string_types):
                 e = GeoIPException
             else:
                 e = TypeError
-            self.assertRaises(e, GeoIP, bad, 0)
+            with self.assertRaises(e):
+                GeoIP(bad, 0)
 
     def test02_bad_query(self):
         "Testing GeoIP query parameter checking."
         cntry_g = GeoIP(city='<foo>')
         # No city database available, these calls should fail.
-        self.assertRaises(GeoIPException, cntry_g.city, 'google.com')
-        self.assertRaises(GeoIPException, cntry_g.coords, 'yahoo.com')
+        with self.assertRaises(GeoIPException):
+            cntry_g.city('google.com')
+        with self.assertRaises(GeoIPException):
+            cntry_g.coords('yahoo.com')
 
         # Non-string query should raise TypeError
-        self.assertRaises(TypeError, cntry_g.country_code, 17)
-        self.assertRaises(TypeError, cntry_g.country_name, GeoIP)
+        with self.assertRaises(TypeError):
+            cntry_g.country_code(17)
+        with self.assertRaises(TypeError):
+            cntry_g.country_name(GeoIP)
 
     def test03_country(self):
         "Testing GeoIP country querying methods."

tests/gis_tests/test_geoip2.py

@@ -47,23 +47,29 @@ class GeoIPTest(unittest.TestCase):
         # Improper parameters.
         bad_params = (23, 'foo', 15.23)
         for bad in bad_params:
-            self.assertRaises(GeoIP2Exception, GeoIP2, cache=bad)
+            with self.assertRaises(GeoIP2Exception):
+                GeoIP2(cache=bad)
             if isinstance(bad, six.string_types):
                 e = GeoIP2Exception
             else:
                 e = TypeError
-            self.assertRaises(e, GeoIP2, bad, 0)
+            with self.assertRaises(e):
+                GeoIP2(bad, 0)
 
     def test02_bad_query(self):
         "GeoIP query parameter checking."
         cntry_g = GeoIP2(city='<foo>')
         # No city database available, these calls should fail.
-        self.assertRaises(GeoIP2Exception, cntry_g.city, 'tmc.edu')
-        self.assertRaises(GeoIP2Exception, cntry_g.coords, 'tmc.edu')
+        with self.assertRaises(GeoIP2Exception):
+            cntry_g.city('tmc.edu')
+        with self.assertRaises(GeoIP2Exception):
+            cntry_g.coords('tmc.edu')
 
         # Non-string query should raise TypeError
-        self.assertRaises(TypeError, cntry_g.country_code, 17)
-        self.assertRaises(TypeError, cntry_g.country_name, GeoIP2)
+        with self.assertRaises(TypeError):
+            cntry_g.country_code(17)
+        with self.assertRaises(TypeError):
+            cntry_g.country_name(GeoIP2)
 
     @mock.patch('socket.gethostbyname')
     def test03_country(self, gethostbyname):

tests/gis_tests/test_measure.py

@@ -34,7 +34,8 @@ class DistanceTest(unittest.TestCase):
 
     def testInitInvalid(self):
         "Testing initialization from invalid units"
-        self.assertRaises(AttributeError, D, banana=100)
+        with self.assertRaises(AttributeError):
+            D(banana=100)
 
     def testAccess(self):
         "Testing access in different units"
@@ -161,7 +162,8 @@ class AreaTest(unittest.TestCase):
 
     def testInitInvaliA(self):
         "Testing initialization from invalid units"
-        self.assertRaises(AttributeError, A, banana=100)
+        with self.assertRaises(AttributeError):
+            A(banana=100)
 
     def testAccess(self):
         "Testing access in different units"

tests/gis_tests/tests.py

@@ -87,8 +87,10 @@ class TestPostgisVersionCheck(unittest.TestCase):
 
         for version in versions:
             ops = FakePostGISOperations(version)
-            self.assertRaises(Exception, lambda: ops.spatial_version)
+            with self.assertRaises(Exception):
+                ops.spatial_version
 
     def test_no_version_number(self):
         ops = FakePostGISOperations()
-        self.assertRaises(ImproperlyConfigured, lambda: ops.spatial_version)
+        with self.assertRaises(ImproperlyConfigured):
+            ops.spatial_version

tests/httpwrappers/tests.py

@@ -31,17 +31,25 @@ class QueryDictTests(unittest.TestCase):
 
     def test_missing_key(self):
         q = QueryDict()
-        self.assertRaises(KeyError, q.__getitem__, 'foo')
+        with self.assertRaises(KeyError):
+            q.__getitem__('foo')
 
     def test_immutability(self):
         q = QueryDict()
-        self.assertRaises(AttributeError, q.__setitem__, 'something', 'bar')
-        self.assertRaises(AttributeError, q.setlist, 'foo', ['bar'])
-        self.assertRaises(AttributeError, q.appendlist, 'foo', ['bar'])
-        self.assertRaises(AttributeError, q.update, {'foo': 'bar'})
-        self.assertRaises(AttributeError, q.pop, 'foo')
-        self.assertRaises(AttributeError, q.popitem)
-        self.assertRaises(AttributeError, q.clear)
+        with self.assertRaises(AttributeError):
+            q.__setitem__('something', 'bar')
+        with self.assertRaises(AttributeError):
+            q.setlist('foo', ['bar'])
+        with self.assertRaises(AttributeError):
+            q.appendlist('foo', ['bar'])
+        with self.assertRaises(AttributeError):
+            q.update({'foo': 'bar'})
+        with self.assertRaises(AttributeError):
+            q.pop('foo')
+        with self.assertRaises(AttributeError):
+            q.popitem()
+        with self.assertRaises(AttributeError):
+            q.clear()
 
     def test_immutable_get_with_default(self):
         q = QueryDict()
@@ -65,16 +73,20 @@ class QueryDictTests(unittest.TestCase):
 
         q = QueryDict(str('foo=bar'))
         self.assertEqual(q['foo'], 'bar')
-        self.assertRaises(KeyError, q.__getitem__, 'bar')
-        self.assertRaises(AttributeError, q.__setitem__, 'something', 'bar')
+        with self.assertRaises(KeyError):
+            q.__getitem__('bar')
+        with self.assertRaises(AttributeError):
+            q.__setitem__('something', 'bar')
 
         self.assertEqual(q.get('foo', 'default'), 'bar')
         self.assertEqual(q.get('bar', 'default'), 'default')
         self.assertEqual(q.getlist('foo'), ['bar'])
         self.assertEqual(q.getlist('bar'), [])
 
-        self.assertRaises(AttributeError, q.setlist, 'foo', ['bar'])
-        self.assertRaises(AttributeError, q.appendlist, 'foo', ['bar'])
+        with self.assertRaises(AttributeError):
+            q.setlist('foo', ['bar'])
+        with self.assertRaises(AttributeError):
+            q.appendlist('foo', ['bar'])
 
         if six.PY2:
             self.assertTrue(q.has_key('foo'))
@@ -89,11 +101,16 @@ class QueryDictTests(unittest.TestCase):
         self.assertEqual(list(six.itervalues(q)), ['bar'])
         self.assertEqual(len(q), 1)
 
-        self.assertRaises(AttributeError, q.update, {'foo': 'bar'})
-        self.assertRaises(AttributeError, q.pop, 'foo')
-        self.assertRaises(AttributeError, q.popitem)
-        self.assertRaises(AttributeError, q.clear)
-        self.assertRaises(AttributeError, q.setdefault, 'foo', 'bar')
+        with self.assertRaises(AttributeError):
+            q.update({'foo': 'bar'})
+        with self.assertRaises(AttributeError):
+            q.pop('foo')
+        with self.assertRaises(AttributeError):
+            q.popitem()
+        with self.assertRaises(AttributeError):
+            q.clear()
+        with self.assertRaises(AttributeError):
+            q.setdefault('foo', 'bar')
 
         self.assertEqual(q.urlencode(), 'foo=bar')
 
@@ -110,7 +127,8 @@ class QueryDictTests(unittest.TestCase):
     def test_mutable_copy(self):
         """A copy of a QueryDict is mutable."""
         q = QueryDict().copy()
-        self.assertRaises(KeyError, q.__getitem__, "foo")
+        with self.assertRaises(KeyError):
+            q.__getitem__("foo")
         q['name'] = 'john'
         self.assertEqual(q['name'], 'john')
 
@@ -169,16 +187,20 @@ class QueryDictTests(unittest.TestCase):
         q = QueryDict(str('vote=yes&vote=no'))
 
         self.assertEqual(q['vote'], 'no')
-        self.assertRaises(AttributeError, q.__setitem__, 'something', 'bar')
+        with self.assertRaises(AttributeError):
+            q.__setitem__('something', 'bar')
 
         self.assertEqual(q.get('vote', 'default'), 'no')
         self.assertEqual(q.get('foo', 'default'), 'default')
         self.assertEqual(q.getlist('vote'), ['yes', 'no'])
         self.assertEqual(q.getlist('foo'), [])
 
-        self.assertRaises(AttributeError, q.setlist, 'foo', ['bar', 'baz'])
-        self.assertRaises(AttributeError, q.setlist, 'foo', ['bar', 'baz'])
-        self.assertRaises(AttributeError, q.appendlist, 'foo', ['bar'])
+        with self.assertRaises(AttributeError):
+            q.setlist('foo', ['bar', 'baz'])
+        with self.assertRaises(AttributeError):
+            q.setlist('foo', ['bar', 'baz'])
+        with self.assertRaises(AttributeError):
+            q.appendlist('foo', ['bar'])
 
         if six.PY2:
             self.assertEqual(q.has_key('vote'), True)
@@ -192,12 +214,18 @@ class QueryDictTests(unittest.TestCase):
         self.assertEqual(list(six.itervalues(q)), ['no'])
         self.assertEqual(len(q), 1)
 
-        self.assertRaises(AttributeError, q.update, {'foo': 'bar'})
-        self.assertRaises(AttributeError, q.pop, 'foo')
-        self.assertRaises(AttributeError, q.popitem)
-        self.assertRaises(AttributeError, q.clear)
-        self.assertRaises(AttributeError, q.setdefault, 'foo', 'bar')
-        self.assertRaises(AttributeError, q.__delitem__, 'vote')
+        with self.assertRaises(AttributeError):
+            q.update({'foo': 'bar'})
+        with self.assertRaises(AttributeError):
+            q.pop('foo')
+        with self.assertRaises(AttributeError):
+            q.popitem()
+        with self.assertRaises(AttributeError):
+            q.clear()
+        with self.assertRaises(AttributeError):
+            q.setdefault('foo', 'bar')
+        with self.assertRaises(AttributeError):
+            q.__delitem__('vote')
 
     if six.PY2:
         def test_invalid_input_encoding(self):
@@ -295,8 +323,10 @@ class HttpResponseTests(unittest.TestCase):
         self.assertIsInstance(l[0][0], str)
 
         r = HttpResponse()
-        self.assertRaises(UnicodeError, r.__setitem__, 'føø', 'bar')
-        self.assertRaises(UnicodeError, r.__setitem__, 'føø'.encode('utf-8'), 'bar')
+        with self.assertRaises(UnicodeError):
+            r.__setitem__('føø', 'bar')
+        with self.assertRaises(UnicodeError):
+            r.__setitem__('føø'.encode('utf-8'), 'bar')
 
     def test_long_line(self):
         # Bug #20889: long lines trigger newlines to be added to headers
@@ -312,8 +342,10 @@ class HttpResponseTests(unittest.TestCase):
     def test_newlines_in_headers(self):
         # Bug #10188: Do not allow newlines in headers (CR or LF)
         r = HttpResponse()
-        self.assertRaises(BadHeaderError, r.__setitem__, 'test\rstr', 'test')
-        self.assertRaises(BadHeaderError, r.__setitem__, 'test\nstr', 'test')
+        with self.assertRaises(BadHeaderError):
+            r.__setitem__('test\rstr', 'test')
+        with self.assertRaises(BadHeaderError):
+            r.__setitem__('test\nstr', 'test')
 
     def test_dict_behavior(self):
         """
@@ -418,10 +450,10 @@ class HttpResponseTests(unittest.TestCase):
             'file:///etc/passwd',
         ]
         for url in bad_urls:
-            self.assertRaises(SuspiciousOperation,
-                              HttpResponseRedirect, url)
-            self.assertRaises(SuspiciousOperation,
-                              HttpResponsePermanentRedirect, url)
+            with self.assertRaises(SuspiciousOperation):
+                HttpResponseRedirect(url)
+            with self.assertRaises(SuspiciousOperation):
+                HttpResponsePermanentRedirect(url)
 
 
 class HttpResponseSubclassesTests(SimpleTestCase):

tests/i18n/patterns/tests.py

@@ -77,7 +77,8 @@ class URLPrefixTests(URLTestCaseBase):
 
     @override_settings(ROOT_URLCONF='i18n.patterns.urls.wrong')
     def test_invalid_prefix_use(self):
-        self.assertRaises(ImproperlyConfigured, lambda: reverse('account:register'))
+        with self.assertRaises(ImproperlyConfigured):
+            reverse('account:register')
 
 
 @override_settings(ROOT_URLCONF='i18n.patterns.urls.disabled')

tests/i18n/tests.py

@@ -1852,7 +1852,8 @@ class TranslationFilesMissing(SimpleTestCase):
         '''
         self.patchGettextFind()
         trans_real._translations = {}
-        self.assertRaises(IOError, activate, 'en')
+        with self.assertRaises(IOError):
+            activate('en')
 
 
 class NonDjangoLanguageTests(SimpleTestCase):

tests/inline_formsets/tests.py

@@ -135,11 +135,9 @@ class InlineFormsetFactoryTest(TestCase):
         If we specify fk_name, but it isn't a ForeignKey from the child model
         to the parent model, we should get an exception.
         """
-        self.assertRaises(
-            Exception,
-            "fk_name 'school' is not a ForeignKey to <class 'inline_formsets.models.Parent'>",
-            inlineformset_factory, Parent, Child, fk_name='school'
-        )
+        msg = "fk_name 'school' is not a ForeignKey to 'inline_formsets.Parent'."
+        with self.assertRaisesMessage(ValueError, msg):
+            inlineformset_factory(Parent, Child, fk_name='school')
 
     def test_non_foreign_key_field(self):
         """

tests/lookup/tests.py

@@ -136,7 +136,8 @@ class LookupTests(TestCase):
         self.assertEqual(Article.objects.in_bulk([]), {})
         self.assertEqual(Article.objects.in_bulk(iter([self.a1.id])), {self.a1.id: self.a1})
         self.assertEqual(Article.objects.in_bulk(iter([])), {})
-        self.assertRaises(TypeError, Article.objects.in_bulk, headline__startswith='Blah')
+        with self.assertRaises(TypeError):
+            Article.objects.in_bulk(headline__startswith='Blah')
 
     def test_values(self):
         # values() returns a list of dictionaries instead of object instances --
@@ -260,9 +261,8 @@ class LookupTests(TestCase):
         # However, an exception FieldDoesNotExist will be thrown if you specify
         # a non-existent field name in values() (a field that is neither in the
         # model nor in extra(select)).
-        self.assertRaises(FieldError,
-            Article.objects.extra(select={'id_plus_one': 'id + 1'}).values,
-            'id', 'id_plus_two')
+        with self.assertRaises(FieldError):
+            Article.objects.extra(select={'id_plus_one': 'id + 1'}).values('id', 'id_plus_two')
         # If you don't specify field names to values(), all are returned.
         self.assertQuerysetEqual(Article.objects.filter(id=self.a5.id).values(),
             [{
@@ -344,7 +344,8 @@ class LookupTests(TestCase):
                 (self.au2.name, self.a6.headline, self.t3.name),
                 (self.au2.name, self.a7.headline, self.t3.name),
             ], transform=identity)
-        self.assertRaises(TypeError, Article.objects.values_list, 'id', 'headline', flat=True)
+        with self.assertRaises(TypeError):
+            Article.objects.values_list('id', 'headline', flat=True)
 
     def test_get_next_previous_by(self):
         # Every DateField and DateTimeField creates get_next_by_FOO() and
@@ -361,7 +362,8 @@ class LookupTests(TestCase):
                          '<Article: Article 7>')
         self.assertEqual(repr(self.a4.get_next_by_pub_date()),
                          '<Article: Article 6>')
-        self.assertRaises(Article.DoesNotExist, self.a5.get_next_by_pub_date)
+        with self.assertRaises(Article.DoesNotExist):
+            self.a5.get_next_by_pub_date()
         self.assertEqual(repr(self.a6.get_next_by_pub_date()),
                          '<Article: Article 5>')
         self.assertEqual(repr(self.a7.get_next_by_pub_date()),

tests/m2m_through_regress/tests.py

@@ -67,10 +67,12 @@ class M2MThroughTestCase(TestCase):
             self.roll.members.set([])
 
     def test_cannot_use_create_on_m2m_with_intermediary_model(self):
-        self.assertRaises(AttributeError, self.rock.members.create, name="Anne")
+        with self.assertRaises(AttributeError):
+            self.rock.members.create(name="Anne")
 
     def test_cannot_use_create_on_reverse_m2m_with_intermediary_model(self):
-        self.assertRaises(AttributeError, self.bob.group_set.create, name="Funk")
+        with self.assertRaises(AttributeError):
+            self.bob.group_set.create(name="Funk")
 
     def test_retrieve_reverse_m2m_items_via_custom_id_intermediary(self):
         self.assertQuerysetEqual(

tests/mail/tests.py

@@ -143,11 +143,13 @@ class MailTests(HeadersCheckMixin, SimpleTestCase):
 
     def test_header_injection(self):
         email = EmailMessage('Subject\nInjection Test', 'Content', 'from@example.com', ['to@example.com'])
-        self.assertRaises(BadHeaderError, email.message)
+        with self.assertRaises(BadHeaderError):
+            email.message()
         email = EmailMessage(
             ugettext_lazy('Subject\nInjection Test'), 'Content', 'from@example.com', ['to@example.com']
         )
-        self.assertRaises(BadHeaderError, email.message)
+        with self.assertRaises(BadHeaderError):
+            email.message()
 
     def test_space_continuation(self):
         """
@@ -1193,7 +1195,8 @@ class SMTPBackendTests(BaseEmailBackendTests, SMTPBackendTestsBase):
         backend = smtp.EmailBackend()
         self.assertTrue(backend.use_ssl)
         try:
-            self.assertRaises(SSLError, backend.open)
+            with self.assertRaises(SSLError):
+                backend.open()
         finally:
             backend.close()
 

tests/many_to_many/tests.py

@@ -33,7 +33,8 @@ class ManyToManyTests(TestCase):
         # Create an Article.
         a5 = Article(id=None, headline='Django lets you reate Web apps easily')
         # You can't associate it with a Publication until it's been saved.
-        self.assertRaises(ValueError, getattr, a5, 'publications')
+        with self.assertRaises(ValueError):
+            getattr(a5, 'publications')
         # Save it!
         a5.save()
         # Associate the Article with a Publication.

tests/many_to_one/tests.py

@@ -455,8 +455,8 @@ class ManyToOneTests(TestCase):
         self.assertEqual(a3.reporter.id, self.r2.id)
 
         # Get should respect explicit foreign keys as well.
-        self.assertRaises(MultipleObjectsReturned,
-                          Article.objects.get, reporter_id=self.r.id)
+        with self.assertRaises(MultipleObjectsReturned):
+            Article.objects.get(reporter_id=self.r.id)
         self.assertEqual(repr(a3),
                          repr(Article.objects.get(reporter_id=self.r2.id,
                                              pub_date=datetime.date(2011, 5, 7))))
@@ -537,15 +537,19 @@ class ManyToOneTests(TestCase):
         self.assertIsNone(p.bestchild)
 
         # Assigning None fails: Child.parent is null=False.
-        self.assertRaises(ValueError, setattr, c, "parent", None)
+        with self.assertRaises(ValueError):
+            setattr(c, "parent", None)
 
         # You also can't assign an object of the wrong type here
-        self.assertRaises(ValueError, setattr, c, "parent", First(id=1, second=1))
+        with self.assertRaises(ValueError):
+            setattr(c, "parent", First(id=1, second=1))
 
         # Nor can you explicitly assign None to Child.parent during object
         # creation (regression for #9649).
-        self.assertRaises(ValueError, Child, name='xyzzy', parent=None)
-        self.assertRaises(ValueError, Child.objects.create, name='xyzzy', parent=None)
+        with self.assertRaises(ValueError):
+            Child(name='xyzzy', parent=None)
+        with self.assertRaises(ValueError):
+            Child.objects.create(name='xyzzy', parent=None)
 
         # Creation using keyword argument should cache the related object.
         p = Parent.objects.get(name="Parent")
@@ -602,7 +606,8 @@ class ManyToOneTests(TestCase):
 
         p = Parent.objects.create(name="Parent")
         c = Child.objects.create(name="Child", parent=p)
-        self.assertRaises(ValueError, Child.objects.create, name="Grandchild", parent=c)
+        with self.assertRaises(ValueError):
+            Child.objects.create(name="Grandchild", parent=c)
 
     def test_fk_instantiation_outside_model(self):
         # Regression for #12190 -- Should be able to instantiate a FK outside
@@ -650,7 +655,8 @@ class ManyToOneTests(TestCase):
         School.objects.use_for_related_fields = True
         try:
             private_student = Student.objects.get(pk=private_student.pk)
-            self.assertRaises(School.DoesNotExist, lambda: private_student.school)
+            with self.assertRaises(School.DoesNotExist):
+                private_student.school
         finally:
             School.objects.use_for_related_fields = False
 

tests/many_to_one_null/tests.py

@@ -44,7 +44,8 @@ class ManyToOneNullTests(TestCase):
         self.assertEqual(self.a3.reporter, None)
         # Need to reget a3 to refresh the cache
         a3 = Article.objects.get(pk=self.a3.pk)
-        self.assertRaises(AttributeError, getattr, a3.reporter, 'id')
+        with self.assertRaises(AttributeError):
+            getattr(a3.reporter, 'id')
         # Accessing an article's 'reporter' attribute returns None
         # if the reporter is set to None.
         self.assertEqual(a3.reporter, None)
@@ -71,7 +72,8 @@ class ManyToOneNullTests(TestCase):
     def test_remove_from_wrong_set(self):
         self.assertQuerysetEqual(self.r2.article_set.all(), ['<Article: Fourth>'])
         # Try to remove a4 from a set it does not belong to
-        self.assertRaises(Reporter.DoesNotExist, self.r.article_set.remove, self.a4)
+        with self.assertRaises(Reporter.DoesNotExist):
+            self.r.article_set.remove(self.a4)
         self.assertQuerysetEqual(self.r2.article_set.all(), ['<Article: Fourth>'])
 
     def test_set(self):

tests/messages_tests/base.py

@@ -238,8 +238,8 @@ class BaseTests(object):
         reverse('show_message')
         for level in ('debug', 'info', 'success', 'warning', 'error'):
             add_url = reverse('add_message', args=(level,))
-            self.assertRaises(MessageFailure, self.client.post, add_url,
-                              data, follow=True)
+            with self.assertRaises(MessageFailure):
+                self.client.post(add_url, data, follow=True)
 
     @modify_settings(
         INSTALLED_APPS={'remove': 'django.contrib.messages'},

tests/middleware_exceptions/tests.py

@@ -862,7 +862,8 @@ class RootUrlconfTests(SimpleTestCase):
         # Removing ROOT_URLCONF is safe, as override_settings will restore
         # the previously defined settings.
         del settings.ROOT_URLCONF
-        self.assertRaises(AttributeError, self.client.get, "/middleware_exceptions/view/")
+        with self.assertRaises(AttributeError):
+            self.client.get("/middleware_exceptions/view/")
 
 
 class MyMiddleware(object):

tests/migrations/test_graph.py

@@ -145,10 +145,8 @@ class GraphTests(SimpleTestCase):
         graph.add_dependency("app_b.0002", ("app_b", "0002"), ("app_b", "0001"))
         graph.add_dependency("app_b.0001", ("app_b", "0001"), ("app_a", "0003"))
         # Test whole graph
-        self.assertRaises(
-            CircularDependencyError,
-            graph.forwards_plan, ("app_a", "0003"),
-        )
+        with self.assertRaises(CircularDependencyError):
+            graph.forwards_plan(("app_a", "0003"), )
 
     def test_circular_graph_2(self):
         graph = MigrationGraph()
@@ -159,10 +157,8 @@ class GraphTests(SimpleTestCase):
         graph.add_dependency('B.0001', ('B', '0001'), ('A', '0001'))
         graph.add_dependency('C.0001', ('C', '0001'), ('B', '0001'))
 
-        self.assertRaises(
-            CircularDependencyError,
-            graph.forwards_plan, ('C', '0001')
-        )
+        with self.assertRaises(CircularDependencyError):
+            graph.forwards_plan(('C', '0001'))
 
     def test_graph_recursive(self):
         graph = MigrationGraph()

tests/model_fields/test_imagefield.py

@@ -83,8 +83,10 @@ class ImageFieldTestMixin(SerializeMixin):
         field = getattr(instance, field_name)
         # Check height/width attributes of field.
         if width is None and height is None:
-            self.assertRaises(ValueError, getattr, field, 'width')
-            self.assertRaises(ValueError, getattr, field, 'height')
+            with self.assertRaises(ValueError):
+                getattr(field, 'width')
+            with self.assertRaises(ValueError):
+                getattr(field, 'height')
         else:
             self.assertEqual(field.width, width)
             self.assertEqual(field.height, height)

tests/model_fields/tests.py

@@ -129,7 +129,8 @@ class DecimalFieldTests(test.TestCase):
         f = models.DecimalField(max_digits=4, decimal_places=2)
         self.assertEqual(f.to_python(3), Decimal("3"))
         self.assertEqual(f.to_python("3.14"), Decimal("3.14"))
-        self.assertRaises(ValidationError, f.to_python, "abc")
+        with self.assertRaises(ValidationError):
+            f.to_python("abc")
 
     def test_default(self):
         f = models.DecimalField(default=Decimal("0.00"))
@@ -598,7 +599,8 @@ class SlugFieldTests(test.TestCase):
 class ValidationTest(test.SimpleTestCase):
     def test_charfield_raises_error_on_empty_string(self):
         f = models.CharField()
-        self.assertRaises(ValidationError, f.clean, "", None)
+        with self.assertRaises(ValidationError):
+            f.clean("", None)
 
     def test_charfield_cleans_empty_string_when_blank_true(self):
         f = models.CharField(blank=True)
@@ -610,7 +612,8 @@ class ValidationTest(test.SimpleTestCase):
 
     def test_integerfield_raises_error_on_invalid_intput(self):
         f = models.IntegerField()
-        self.assertRaises(ValidationError, f.clean, "a", None)
+        with self.assertRaises(ValidationError):
+            f.clean("a", None)
 
     def test_charfield_with_choices_cleans_valid_choice(self):
         f = models.CharField(max_length=1,
@@ -619,7 +622,8 @@ class ValidationTest(test.SimpleTestCase):
 
     def test_charfield_with_choices_raises_error_on_invalid_choice(self):
         f = models.CharField(choices=[('a', 'A'), ('b', 'B')])
-        self.assertRaises(ValidationError, f.clean, "not a", None)
+        with self.assertRaises(ValidationError):
+            f.clean("not a", None)
 
     def test_charfield_get_choices_with_blank_defined(self):
         f = models.CharField(choices=[('', '<><>'), ('a', 'A')])
@@ -639,7 +643,8 @@ class ValidationTest(test.SimpleTestCase):
 
     def test_nullable_integerfield_raises_error_with_blank_false(self):
         f = models.IntegerField(null=True, blank=False)
-        self.assertRaises(ValidationError, f.clean, None, None)
+        with self.assertRaises(ValidationError):
+            f.clean(None, None)
 
     def test_nullable_integerfield_cleans_none_on_null_and_blank_true(self):
         f = models.IntegerField(null=True, blank=True)
@@ -647,16 +652,20 @@ class ValidationTest(test.SimpleTestCase):
 
     def test_integerfield_raises_error_on_empty_input(self):
         f = models.IntegerField(null=False)
-        self.assertRaises(ValidationError, f.clean, None, None)
-        self.assertRaises(ValidationError, f.clean, '', None)
+        with self.assertRaises(ValidationError):
+            f.clean(None, None)
+        with self.assertRaises(ValidationError):
+            f.clean('', None)
 
     def test_integerfield_validates_zero_against_choices(self):
         f = models.IntegerField(choices=((1, 1),))
-        self.assertRaises(ValidationError, f.clean, '0', None)
+        with self.assertRaises(ValidationError):
+            f.clean('0', None)
 
     def test_charfield_raises_error_on_empty_input(self):
         f = models.CharField(null=False)
-        self.assertRaises(ValidationError, f.clean, None, None)
+        with self.assertRaises(ValidationError):
+            f.clean(None, None)
 
     def test_datefield_cleans_date(self):
         f = models.DateField()
@@ -664,7 +673,8 @@ class ValidationTest(test.SimpleTestCase):
 
     def test_boolean_field_doesnt_accept_empty_input(self):
         f = models.BooleanField()
-        self.assertRaises(ValidationError, f.clean, None, None)
+        with self.assertRaises(ValidationError):
+            f.clean(None, None)
 
 
 class IntegerFieldTests(test.TestCase):
@@ -864,7 +874,8 @@ class BinaryFieldTests(test.TestCase):
 
     def test_max_length(self):
         dm = DataModel(short_data=self.binary_data * 4)
-        self.assertRaises(ValidationError, dm.full_clean)
+        with self.assertRaises(ValidationError):
+            dm.full_clean()
 
 
 class GenericIPAddressFieldTests(test.TestCase):
@@ -875,10 +886,12 @@ class GenericIPAddressFieldTests(test.TestCase):
         """
         model_field = models.GenericIPAddressField(protocol='IPv4')
         form_field = model_field.formfield()
-        self.assertRaises(ValidationError, form_field.clean, '::1')
+        with self.assertRaises(ValidationError):
+            form_field.clean('::1')
         model_field = models.GenericIPAddressField(protocol='IPv6')
         form_field = model_field.formfield()
-        self.assertRaises(ValidationError, form_field.clean, '127.0.0.1')
+        with self.assertRaises(ValidationError):
+            form_field.clean('127.0.0.1')
 
     def test_null_value(self):
         """

tests/model_forms/tests.py

@@ -177,7 +177,8 @@ class ModelFormBaseTest(TestCase):
     def test_no_model_class(self):
         class NoModelModelForm(forms.ModelForm):
             pass
-        self.assertRaises(ValueError, NoModelModelForm)
+        with self.assertRaises(ValueError):
+            NoModelModelForm()
 
     def test_empty_fields_to_fields_for_model(self):
         """
@@ -282,8 +283,8 @@ class ModelFormBaseTest(TestCase):
             self.fail('Declarative field raised FieldError incorrectly')
 
     def test_extra_field_modelform_factory(self):
-        self.assertRaises(FieldError, modelform_factory,
-                          Person, fields=['no-field', 'name'])
+        with self.assertRaises(FieldError):
+            modelform_factory(Person, fields=['no-field', 'name'])
 
     def test_replace_field(self):
         class ReplaceField(forms.ModelForm):
@@ -1836,7 +1837,8 @@ class FileAndImageFieldTests(TestCase):
         """
         f = forms.FileField(required=True)
         self.assertEqual(f.clean(False, 'initial'), 'initial')
-        self.assertRaises(ValidationError, f.clean, False)
+        with self.assertRaises(ValidationError):
+            f.clean(False)
 
     def test_full_clear(self):
         """
@@ -2682,8 +2684,8 @@ class FormFieldCallbackTests(SimpleTestCase):
 
     def test_bad_callback(self):
         # A bad callback provided by user still gives an error
-        self.assertRaises(TypeError, modelform_factory, Person, fields="__all__",
-                          formfield_callback='not a function or callable')
+        with self.assertRaises(TypeError):
+            modelform_factory(Person, fields="__all__", formfield_callback='not a function or callable')
 
 
 class LocalizedModelFormTest(TestCase):

tests/model_inheritance/tests.py

@@ -48,14 +48,16 @@ class ModelInheritanceTests(TestCase):
 
         # However, the CommonInfo class cannot be used as a normal model (it
         # doesn't exist as a model).
-        self.assertRaises(AttributeError, lambda: CommonInfo.objects.all())
+        with self.assertRaises(AttributeError):
+            CommonInfo.objects.all()
 
     def test_reverse_relation_for_different_hierarchy_tree(self):
         # Even though p.supplier for a Place 'p' (a parent of a Supplier), a
         # Restaurant object cannot access that reverse relation, since it's not
         # part of the Place-Supplier Hierarchy.
         self.assertQuerysetEqual(Place.objects.filter(supplier__name="foo"), [])
-        self.assertRaises(FieldError, Restaurant.objects.filter, supplier__name="foo")
+        with self.assertRaises(FieldError):
+            Restaurant.objects.filter(supplier__name="foo")
 
     def test_model_with_distinct_accessors(self):
         # The Post model has distinct accessors for the Comment and Link models.
@@ -68,9 +70,8 @@ class ModelInheritanceTests(TestCase):
 
         # The Post model doesn't have an attribute called
         # 'attached_%(class)s_set'.
-        self.assertRaises(
-            AttributeError, getattr, post, "attached_%(class)s_set"
-        )
+        with self.assertRaises(AttributeError):
+            getattr(post, "attached_%(class)s_set")
 
     def test_model_with_distinct_related_query_name(self):
         self.assertQuerysetEqual(Post.objects.filter(attached_model_inheritance_comments__is_spam=True), [])
@@ -220,25 +221,19 @@ class ModelInheritanceDataTests(TestCase):
     def test_parent_child_one_to_one_link_on_nonrelated_objects(self):
         # This won't work because the Demon Dogs restaurant is not an Italian
         # restaurant.
-        self.assertRaises(
-            ItalianRestaurant.DoesNotExist,
-            lambda: Place.objects.get(name="Demon Dogs").restaurant.italianrestaurant
-        )
+        with self.assertRaises(ItalianRestaurant.DoesNotExist):
+            Place.objects.get(name="Demon Dogs").restaurant.italianrestaurant
 
     def test_inherited_does_not_exist_exception(self):
         # An ItalianRestaurant which does not exist is also a Place which does
         # not exist.
-        self.assertRaises(
-            Place.DoesNotExist,
-            ItalianRestaurant.objects.get, name="The Noodle Void"
-        )
+        with self.assertRaises(Place.DoesNotExist):
+            ItalianRestaurant.objects.get(name="The Noodle Void")
 
     def test_inherited_multiple_objects_returned_exception(self):
         # MultipleObjectsReturned is also inherited.
-        self.assertRaises(
-            Place.MultipleObjectsReturned,
-            Restaurant.objects.get, id__lt=12321
-        )
+        with self.assertRaises(Place.MultipleObjectsReturned):
+            Restaurant.objects.get(id__lt=12321)
 
     def test_related_objects_for_inherited_models(self):
         # Related objects work just as they normally do.
@@ -250,9 +245,8 @@ class ModelInheritanceDataTests(TestCase):
         # This won't work because the Place we select is not a Restaurant (it's
         # a Supplier).
         p = Place.objects.get(name="Joe's Chickens")
-        self.assertRaises(
-            Restaurant.DoesNotExist, lambda: p.restaurant
-        )
+        with self.assertRaises(Restaurant.DoesNotExist):
+            p.restaurant
 
         self.assertEqual(p.supplier, s1)
         self.assertQuerysetEqual(

tests/model_inheritance_regress/tests.py

@@ -171,14 +171,10 @@ class ModelInheritanceTest(TestCase):
         # the ItalianRestaurant.
         Restaurant.objects.all().delete()
 
-        self.assertRaises(
-            Place.DoesNotExist,
-            Place.objects.get,
-            pk=ident)
-        self.assertRaises(
-            ItalianRestaurant.DoesNotExist,
-            ItalianRestaurant.objects.get,
-            pk=ident)
+        with self.assertRaises(Place.DoesNotExist):
+            Place.objects.get(pk=ident)
+        with self.assertRaises(ItalianRestaurant.DoesNotExist):
+            ItalianRestaurant.objects.get(pk=ident)
 
     def test_issue_6755(self):
         """
@@ -241,14 +237,12 @@ class ModelInheritanceTest(TestCase):
 
         self.assertEqual(c1.get_next_by_pub_date(), c2)
         self.assertEqual(c2.get_next_by_pub_date(), c3)
-        self.assertRaises(
-            ArticleWithAuthor.DoesNotExist,
-            c3.get_next_by_pub_date)
+        with self.assertRaises(ArticleWithAuthor.DoesNotExist):
+            c3.get_next_by_pub_date()
         self.assertEqual(c3.get_previous_by_pub_date(), c2)
         self.assertEqual(c2.get_previous_by_pub_date(), c1)
-        self.assertRaises(
-            ArticleWithAuthor.DoesNotExist,
-            c1.get_previous_by_pub_date)
+        with self.assertRaises(ArticleWithAuthor.DoesNotExist):
+            c1.get_previous_by_pub_date()
 
     def test_inherited_fields(self):
         """

tests/model_regress/tests.py

@@ -225,7 +225,8 @@ class ModelValidationTest(TestCase):
     def test_pk_validation(self):
         NonAutoPK.objects.create(name="one")
         again = NonAutoPK(name="one")
-        self.assertRaises(ValidationError, again.validate_unique)
+        with self.assertRaises(ValidationError):
+            again.validate_unique()
 
 
 class EvaluateMethodTest(TestCase):

tests/multiple_database/tests.py

@@ -49,11 +49,8 @@ class QueryTestCase(TestCase):
         except Book.DoesNotExist:
             self.fail('"Pro Django" should exist on default database')
 
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.using('other').get,
-            title="Pro Django"
-        )
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('other').get(title="Pro Django")
 
         try:
             Book.objects.get(title="Dive into Python")
@@ -61,11 +58,8 @@ class QueryTestCase(TestCase):
         except Book.DoesNotExist:
             self.fail('"Dive into Python" should exist on default database')
 
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.using('other').get,
-            title="Dive into Python"
-        )
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('other').get(title="Dive into Python")
 
     def test_other_creation(self):
         "Objects created on another database don't leak onto the default database"
@@ -85,32 +79,20 @@ class QueryTestCase(TestCase):
         except Book.DoesNotExist:
             self.fail('"Pro Django" should exist on other database')
 
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.get,
-            title="Pro Django"
-        )
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.using('default').get,
-            title="Pro Django"
-        )
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.get(title="Pro Django")
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(title="Pro Django")
 
         try:
             Book.objects.using('other').get(title="Dive into Python")
         except Book.DoesNotExist:
             self.fail('"Dive into Python" should exist on other database')
 
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.get,
-            title="Dive into Python"
-        )
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.using('default').get,
-            title="Dive into Python"
-        )
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.get(title="Dive into Python")
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(title="Dive into Python")
 
     def test_refresh(self):
         dive = Book()
@@ -137,20 +119,24 @@ class QueryTestCase(TestCase):
 
         dive = Book.objects.using('other').get(published=datetime.date(2009, 5, 4))
         self.assertEqual(dive.title, "Dive into Python")
-        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, published=datetime.date(2009, 5, 4))
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(published=datetime.date(2009, 5, 4))
 
         dive = Book.objects.using('other').get(title__icontains="dive")
         self.assertEqual(dive.title, "Dive into Python")
-        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, title__icontains="dive")
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(title__icontains="dive")
 
         dive = Book.objects.using('other').get(title__iexact="dive INTO python")
         self.assertEqual(dive.title, "Dive into Python")
-        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, title__iexact="dive INTO python")
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(title__iexact="dive INTO python")
 
         dive = Book.objects.using('other').get(published__year=2009)
         self.assertEqual(dive.title, "Dive into Python")
         self.assertEqual(dive.published, datetime.date(2009, 5, 4))
-        self.assertRaises(Book.DoesNotExist, Book.objects.using('default').get, published__year=2009)
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(published__year=2009)
 
         years = Book.objects.using('other').dates('published', 'year')
         self.assertEqual([o.year for o in years], [2009])
@@ -965,7 +951,8 @@ class QueryTestCase(TestCase):
         # When you call __str__ on the query object, it doesn't know about using
         # so it falls back to the default. If the subquery explicitly uses a
         # different database, an error should be raised.
-        self.assertRaises(ValueError, str, qs.query)
+        with self.assertRaises(ValueError):
+            str(qs.query)
 
         # Evaluating the query shouldn't work, either
         with self.assertRaises(ValueError):
@@ -1605,7 +1592,8 @@ class AuthTestCase(TestCase):
         self.assertEqual(alice.username, 'alice')
         self.assertEqual(alice._state.db, 'other')
 
-        self.assertRaises(User.DoesNotExist, User.objects.using('default').get, username='alice')
+        with self.assertRaises(User.DoesNotExist):
+            User.objects.using('default').get(username='alice')
 
         # The second user only exists on the default database
         bob = User.objects.using('default').get(username='bob')
@@ -1613,7 +1601,8 @@ class AuthTestCase(TestCase):
         self.assertEqual(bob.username, 'bob')
         self.assertEqual(bob._state.db, 'default')
 
-        self.assertRaises(User.DoesNotExist, User.objects.using('other').get, username='bob')
+        with self.assertRaises(User.DoesNotExist):
+            User.objects.using('other').get(username='bob')
 
         # That is... there is one user on each database
         self.assertEqual(User.objects.using('default').count(), 1)
@@ -1663,11 +1652,8 @@ class FixtureTestCase(TestCase):
         except Book.DoesNotExist:
             self.fail('"Pro Django" should exist on default database')
 
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.using('other').get,
-            title="Pro Django"
-        )
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('other').get(title="Pro Django")
 
         # Check that "Dive into Python" exists on the default database, but not on other database
         try:
@@ -1675,16 +1661,10 @@ class FixtureTestCase(TestCase):
         except Book.DoesNotExist:
             self.fail('"Dive into Python" should exist on other database')
 
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.get,
-            title="Dive into Python"
-        )
-        self.assertRaises(
-            Book.DoesNotExist,
-            Book.objects.using('default').get,
-            title="Dive into Python"
-        )
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.get(title="Dive into Python")
+        with self.assertRaises(Book.DoesNotExist):
+            Book.objects.using('default').get(title="Dive into Python")
 
         # Check that "Definitive Guide" exists on the both databases
         try:
@@ -1846,7 +1826,8 @@ class RouterAttributeErrorTestCase(TestCase):
         b = Book.objects.create(title="Pro Django",
                                 published=datetime.date(2008, 12, 16))
         with self.override_router():
-            self.assertRaises(AttributeError, Book.objects.get, pk=b.pk)
+            with self.assertRaises(AttributeError):
+                Book.objects.get(pk=b.pk)
 
     def test_attribute_error_save(self):
         "Check that the AttributeError from AttributeErrorRouter bubbles up"
@@ -1854,7 +1835,8 @@ class RouterAttributeErrorTestCase(TestCase):
         dive.title = "Dive into Python"
         dive.published = datetime.date(2009, 5, 4)
         with self.override_router():
-            self.assertRaises(AttributeError, dive.save)
+            with self.assertRaises(AttributeError):
+                dive.save()
 
     def test_attribute_error_delete(self):
         "Check that the AttributeError from AttributeErrorRouter bubbles up"
@@ -1864,7 +1846,8 @@ class RouterAttributeErrorTestCase(TestCase):
         b.authors.set([p])
         b.editor = p
         with self.override_router():
-            self.assertRaises(AttributeError, b.delete)
+            with self.assertRaises(AttributeError):
+                b.delete()
 
     def test_attribute_error_m2m(self):
         "Check that the AttributeError from AttributeErrorRouter bubbles up"

tests/null_queries/tests.py

@@ -40,10 +40,12 @@ class NullQueriesTests(TestCase):
         )
 
         # Valid query, but fails because foo isn't a keyword
-        self.assertRaises(FieldError, Choice.objects.filter, foo__exact=None)
+        with self.assertRaises(FieldError):
+            Choice.objects.filter(foo__exact=None)
 
         # Can't use None on anything other than __exact and __iexact
-        self.assertRaises(ValueError, Choice.objects.filter, id__gt=None)
+        with self.assertRaises(ValueError):
+            Choice.objects.filter(id__gt=None)
 
         # Related managers use __exact=None implicitly if the object hasn't been saved.
         p2 = Poll(question="How?")

tests/one_to_one/tests.py

@@ -229,10 +229,12 @@ class OneToOneTests(TestCase):
         self.assertIsNone(ug_bar.place)
 
         # Assigning None fails: Place.restaurant is null=False
-        self.assertRaises(ValueError, setattr, p, 'restaurant', None)
+        with self.assertRaises(ValueError):
+            setattr(p, 'restaurant', None)
 
         # You also can't assign an object of the wrong type here
-        self.assertRaises(ValueError, setattr, p, 'restaurant', p)
+        with self.assertRaises(ValueError):
+            setattr(p, 'restaurant', p)
 
         # Creation using keyword argument should cache the related object.
         p = Place.objects.get(name="Demon Dogs")
@@ -459,14 +461,16 @@ class OneToOneTests(TestCase):
         School.objects.use_for_related_fields = True
         try:
             private_director = Director._base_manager.get(pk=private_director.pk)
-            self.assertRaises(School.DoesNotExist, lambda: private_director.school)
+            with self.assertRaises(School.DoesNotExist):
+                private_director.school
         finally:
             School.objects.use_for_related_fields = False
 
         Director.objects.use_for_related_fields = True
         try:
             private_school = School._base_manager.get(pk=private_school.pk)
-            self.assertRaises(Director.DoesNotExist, lambda: private_school.director)
+            with self.assertRaises(Director.DoesNotExist):
+                private_school.director
         finally:
             Director.objects.use_for_related_fields = False
 

tests/pagination/tests.py

@@ -114,9 +114,12 @@ class PaginationTests(unittest.TestCase):
         raised.
         """
         paginator = Paginator([1, 2, 3], 2)
-        self.assertRaises(InvalidPage, paginator.page, 3)
-        self.assertRaises(PageNotAnInteger, paginator.validate_number, None)
-        self.assertRaises(PageNotAnInteger, paginator.validate_number, 'x')
+        with self.assertRaises(InvalidPage):
+            paginator.page(3)
+        with self.assertRaises(PageNotAnInteger):
+            paginator.validate_number(None)
+        with self.assertRaises(PageNotAnInteger):
+            paginator.validate_number('x')
         # With no content and allow_empty_first_page=True, 1 is a valid page number
         paginator = Paginator([], 2)
         self.assertEqual(paginator.validate_number(1), 1)
@@ -203,9 +206,12 @@ class PaginationTests(unittest.TestCase):
             self.check_indexes(params, 'last', last)
 
         # When no items and no empty first page, we should get EmptyPage error.
-        self.assertRaises(EmptyPage, self.check_indexes, ([], 4, 0, False), 1, None)
-        self.assertRaises(EmptyPage, self.check_indexes, ([], 4, 1, False), 1, None)
-        self.assertRaises(EmptyPage, self.check_indexes, ([], 4, 2, False), 1, None)
+        with self.assertRaises(EmptyPage):
+            self.check_indexes(([], 4, 0, False), 1, None)
+        with self.assertRaises(EmptyPage):
+            self.check_indexes(([], 4, 1, False), 1, None)
+        with self.assertRaises(EmptyPage):
+            self.check_indexes(([], 4, 2, False), 1, None)
 
     def test_page_sequence(self):
         """
@@ -267,7 +273,8 @@ class ModelPaginationTests(TestCase):
         self.assertFalse(p.has_previous())
         self.assertTrue(p.has_other_pages())
         self.assertEqual(2, p.next_page_number())
-        self.assertRaises(InvalidPage, p.previous_page_number)
+        with self.assertRaises(InvalidPage):
+            p.previous_page_number()
         self.assertEqual(1, p.start_index())
         self.assertEqual(5, p.end_index())
 
@@ -286,7 +293,8 @@ class ModelPaginationTests(TestCase):
         self.assertFalse(p.has_next())
         self.assertTrue(p.has_previous())
         self.assertTrue(p.has_other_pages())
-        self.assertRaises(InvalidPage, p.next_page_number)
+        with self.assertRaises(InvalidPage):
+            p.next_page_number()
         self.assertEqual(1, p.previous_page_number())
         self.assertEqual(6, p.start_index())
         self.assertEqual(9, p.end_index())
@@ -302,7 +310,8 @@ class ModelPaginationTests(TestCase):
         # Make sure object_list queryset is not evaluated by an invalid __getitem__ call.
         # (this happens from the template engine when using eg: {% page_obj.has_previous %})
         self.assertIsNone(p.object_list._result_cache)
-        self.assertRaises(TypeError, lambda: p['has_previous'])
+        with self.assertRaises(TypeError):
+            p['has_previous']
         self.assertIsNone(p.object_list._result_cache)
         self.assertNotIsInstance(p.object_list, list)
 

tests/properties/tests.py

@@ -16,7 +16,8 @@ class PropertyTests(TestCase):
 
     def test_setter(self):
         # The "full_name" property hasn't provided a "set" method.
-        self.assertRaises(AttributeError, setattr, self.a, 'full_name', 'Paul McCartney')
+        with self.assertRaises(AttributeError):
+            setattr(self.a, 'full_name', 'Paul McCartney')
 
         # And cannot be used to initialize the class.
         with self.assertRaisesMessage(TypeError, "'full_name' is an invalid keyword argument"):

tests/proxy_models/tests.py

@@ -93,31 +93,19 @@ class ProxyModelTests(TestCase):
         LowerStatusPerson.objects.create(status="low", name="homer")
         max_id = Person.objects.aggregate(max_id=models.Max('id'))['max_id']
 
-        self.assertRaises(
-            Person.DoesNotExist,
-            MyPersonProxy.objects.get,
-            name='Zathras'
-        )
-        self.assertRaises(
-            Person.MultipleObjectsReturned,
-            MyPersonProxy.objects.get,
-            id__lt=max_id + 1
-        )
-        self.assertRaises(
-            Person.DoesNotExist,
-            StatusPerson.objects.get,
-            name='Zathras'
-        )
+        with self.assertRaises(Person.DoesNotExist):
+            MyPersonProxy.objects.get(name='Zathras')
+        with self.assertRaises(Person.MultipleObjectsReturned):
+            MyPersonProxy.objects.get(id__lt=max_id + 1)
+        with self.assertRaises(Person.DoesNotExist):
+            StatusPerson.objects.get(name='Zathras')
 
         StatusPerson.objects.create(name='Bazza Jr.')
         StatusPerson.objects.create(name='Foo Jr.')
         max_id = Person.objects.aggregate(max_id=models.Max('id'))['max_id']
 
-        self.assertRaises(
-            Person.MultipleObjectsReturned,
-            StatusPerson.objects.get,
-            id__lt=max_id + 1
-        )
+        with self.assertRaises(Person.MultipleObjectsReturned):
+            StatusPerson.objects.get(id__lt=max_id + 1)
 
     def test_abc(self):
         """
@@ -127,7 +115,8 @@ class ProxyModelTests(TestCase):
             class NoAbstract(Abstract):
                 class Meta:
                     proxy = True
-        self.assertRaises(TypeError, build_abc)
+        with self.assertRaises(TypeError):
+            build_abc()
 
     @isolate_apps('proxy_models')
     def test_no_cbc(self):
@@ -138,7 +127,8 @@ class ProxyModelTests(TestCase):
             class TooManyBases(Person, Abstract):
                 class Meta:
                     proxy = True
-        self.assertRaises(TypeError, build_no_cbc)
+        with self.assertRaises(TypeError):
+            build_no_cbc()
 
     @isolate_apps('proxy_models')
     def test_no_base_classes(self):
@@ -146,7 +136,8 @@ class ProxyModelTests(TestCase):
             class NoBaseClasses(models.Model):
                 class Meta:
                     proxy = True
-        self.assertRaises(TypeError, build_no_base_classes)
+        with self.assertRaises(TypeError):
+            build_no_base_classes()
 
     @isolate_apps('proxy_models')
     def test_new_fields(self):

tests/queries/tests.py

@@ -2930,7 +2930,8 @@ class WhereNodeTest(TestCase):
     def test_empty_full_handling_conjunction(self):
         compiler = WhereNodeTest.MockCompiler()
         w = WhereNode(children=[NothingNode()])
-        self.assertRaises(EmptyResultSet, w.as_sql, compiler, connection)
+        with self.assertRaises(EmptyResultSet):
+            w.as_sql(compiler, connection)
         w.negate()
         self.assertEqual(w.as_sql(compiler, connection), ('', []))
         w = WhereNode(children=[self.DummyNode(), self.DummyNode()])
@@ -2938,14 +2939,16 @@ class WhereNodeTest(TestCase):
         w.negate()
         self.assertEqual(w.as_sql(compiler, connection), ('NOT (dummy AND dummy)', []))
         w = WhereNode(children=[NothingNode(), self.DummyNode()])
-        self.assertRaises(EmptyResultSet, w.as_sql, compiler, connection)
+        with self.assertRaises(EmptyResultSet):
+            w.as_sql(compiler, connection)
         w.negate()
         self.assertEqual(w.as_sql(compiler, connection), ('', []))
 
     def test_empty_full_handling_disjunction(self):
         compiler = WhereNodeTest.MockCompiler()
         w = WhereNode(children=[NothingNode()], connector='OR')
-        self.assertRaises(EmptyResultSet, w.as_sql, compiler, connection)
+        with self.assertRaises(EmptyResultSet):
+            w.as_sql(compiler, connection)
         w.negate()
         self.assertEqual(w.as_sql(compiler, connection), ('', []))
         w = WhereNode(children=[self.DummyNode(), self.DummyNode()], connector='OR')
@@ -2987,8 +2990,10 @@ class IteratorExceptionsTest(TestCase):
         # Test for #19895 - second iteration over invalid queryset
         # raises errors.
         qs = Article.objects.order_by('invalid_column')
-        self.assertRaises(FieldError, list, qs)
-        self.assertRaises(FieldError, list, qs)
+        with self.assertRaises(FieldError):
+            list(qs)
+        with self.assertRaises(FieldError):
+            list(qs)
 
 
 class NullJoinPromotionOrTest(TestCase):

tests/raw_query/tests.py

@@ -275,7 +275,8 @@ class RawQueryTests(TestCase):
         first_two = Author.objects.raw(query)[0:2]
         self.assertEqual(len(first_two), 2)
 
-        self.assertRaises(TypeError, lambda: Author.objects.raw(query)['test'])
+        with self.assertRaises(TypeError):
+            Author.objects.raw(query)['test']
 
     def test_inheritance(self):
         # date is the end of the Cuban Missile Crisis, I have no idea when

tests/requests/tests.py

@@ -345,7 +345,8 @@ class RequestsTests(SimpleTestCase):
                                'CONTENT_LENGTH': len(payload),
                                'wsgi.input': payload})
         self.assertEqual(request.read(2), b'na')
-        self.assertRaises(RawPostDataException, lambda: request.body)
+        with self.assertRaises(RawPostDataException):
+            request.body
         self.assertEqual(request.POST, {})
 
     def test_non_ascii_POST(self):
@@ -390,7 +391,8 @@ class RequestsTests(SimpleTestCase):
                                'CONTENT_LENGTH': len(payload),
                                'wsgi.input': payload})
         self.assertEqual(request.POST, {'name': ['value']})
-        self.assertRaises(RawPostDataException, lambda: request.body)
+        with self.assertRaises(RawPostDataException):
+            request.body
 
     def test_body_after_POST_multipart_related(self):
         """

tests/responses/tests.py

@@ -127,7 +127,8 @@ class HttpResponseTests(SimpleTestCase):
         generator = ("{}".format(i) for i in range(10))
         response = HttpResponse(content=generator)
         self.assertEqual(response.content, b'0123456789')
-        self.assertRaises(StopIteration, next, generator)
+        with self.assertRaises(StopIteration):
+            next(generator)
 
         cache.set('my-response-key', response)
         response = cache.get('my-response-key')

tests/reverse_lookup/tests.py

@@ -48,5 +48,5 @@ class ReverseLookupTests(TestCase):
         """
         If a related_name is given you can't use the field name instead
         """
-        self.assertRaises(FieldError, Poll.objects.get,
-            choice__name__exact="This is the answer")
+        with self.assertRaises(FieldError):
+            Poll.objects.get(choice__name__exact="This is the answer")

tests/schema/tests.py

@@ -139,10 +139,8 @@ class SchemaTests(TransactionTestCase):
         with connection.schema_editor() as editor:
             editor.delete_model(Author)
         # Check that it's gone
-        self.assertRaises(
-            DatabaseError,
-            lambda: list(Author.objects.all()),
-        )
+        with self.assertRaises(DatabaseError):
+            list(Author.objects.all())
 
     @skipUnlessDBFeature('supports_foreign_keys')
     def test_fk(self):
@@ -1026,7 +1024,8 @@ class SchemaTests(TransactionTestCase):
         new_field = M2MFieldClass("schema.TagM2MTest", related_name="authors")
         new_field.contribute_to_class(LocalAuthorWithM2M, "tags")
         # Ensure there's no m2m table there
-        self.assertRaises(DatabaseError, self.column_classes, new_field.remote_field.through)
+        with self.assertRaises(DatabaseError):
+            self.column_classes(new_field.remote_field.through)
         # Add the field
         with connection.schema_editor() as editor:
             editor.add_field(LocalAuthorWithM2M, new_field)
@@ -1042,7 +1041,8 @@ class SchemaTests(TransactionTestCase):
         with connection.schema_editor() as editor:
             editor.remove_field(LocalAuthorWithM2M, new_field)
         # Ensure there's no m2m table there
-        self.assertRaises(DatabaseError, self.column_classes, new_field.remote_field.through)
+        with self.assertRaises(DatabaseError):
+            self.column_classes(new_field.remote_field.through)
 
         # Make sure the model state is coherent with the table one now that
         # we've removed the tags field.
@@ -1145,10 +1145,8 @@ class SchemaTests(TransactionTestCase):
         with connection.schema_editor() as editor:
             editor.alter_field(LocalBookWithM2M, old_field, new_field)
         # Ensure old M2M is gone
-        self.assertRaises(
-            DatabaseError,
-            self.column_classes, LocalBookWithM2M._meta.get_field("tags").remote_field.through
-        )
+        with self.assertRaises(DatabaseError):
+            self.column_classes(LocalBookWithM2M._meta.get_field("tags").remote_field.through)
 
         # This model looks like the new model and is used for teardown.
         opts = LocalBookWithM2M._meta
@@ -1217,7 +1215,8 @@ class SchemaTests(TransactionTestCase):
             editor.create_model(Tag)
         # Ensure the field is unique to begin with
         Tag.objects.create(title="foo", slug="foo")
-        self.assertRaises(IntegrityError, Tag.objects.create, title="bar", slug="foo")
+        with self.assertRaises(IntegrityError):
+            Tag.objects.create(title="bar", slug="foo")
         Tag.objects.all().delete()
         # Alter the slug field to be non-unique
         old_field = Tag._meta.get_field("slug")
@@ -1236,7 +1235,8 @@ class SchemaTests(TransactionTestCase):
             editor.alter_field(Tag, new_field, new_field2, strict=True)
         # Ensure the field is unique again
         Tag.objects.create(title="foo", slug="foo")
-        self.assertRaises(IntegrityError, Tag.objects.create, title="bar", slug="foo")
+        with self.assertRaises(IntegrityError):
+            Tag.objects.create(title="bar", slug="foo")
         Tag.objects.all().delete()
         # Rename the field
         new_field3 = SlugField(unique=True)
@@ -1245,7 +1245,8 @@ class SchemaTests(TransactionTestCase):
             editor.alter_field(Tag, new_field2, new_field3, strict=True)
         # Ensure the field is still unique
         TagUniqueRename.objects.create(title="foo", slug2="foo")
-        self.assertRaises(IntegrityError, TagUniqueRename.objects.create, title="bar", slug2="foo")
+        with self.assertRaises(IntegrityError):
+            TagUniqueRename.objects.create(title="bar", slug2="foo")
         Tag.objects.all().delete()
 
     def test_unique_together(self):
@@ -1259,7 +1260,8 @@ class SchemaTests(TransactionTestCase):
         UniqueTest.objects.create(year=2012, slug="foo")
         UniqueTest.objects.create(year=2011, slug="foo")
         UniqueTest.objects.create(year=2011, slug="bar")
-        self.assertRaises(IntegrityError, UniqueTest.objects.create, year=2012, slug="foo")
+        with self.assertRaises(IntegrityError):
+            UniqueTest.objects.create(year=2012, slug="foo")
         UniqueTest.objects.all().delete()
         # Alter the model to its non-unique-together companion
         with connection.schema_editor() as editor:
@@ -1275,7 +1277,8 @@ class SchemaTests(TransactionTestCase):
             editor.alter_unique_together(UniqueTest, [], UniqueTest._meta.unique_together)
         # Ensure the fields are unique again
         UniqueTest.objects.create(year=2012, slug="foo")
-        self.assertRaises(IntegrityError, UniqueTest.objects.create, year=2012, slug="foo")
+        with self.assertRaises(IntegrityError):
+            UniqueTest.objects.create(year=2012, slug="foo")
         UniqueTest.objects.all().delete()
 
     def test_unique_together_with_fk(self):
@@ -1576,10 +1579,8 @@ class SchemaTests(TransactionTestCase):
         with connection.schema_editor() as editor:
             editor.delete_model(Thing)
         # Check that it's gone
-        self.assertRaises(
-            DatabaseError,
-            lambda: list(Thing.objects.all()),
-        )
+        with self.assertRaises(DatabaseError):
+            list(Thing.objects.all())
 
     @skipUnlessDBFeature('supports_foreign_keys')
     def test_remove_constraints_capital_letters(self):

tests/select_for_update/tests.py

@@ -110,11 +110,8 @@ class SelectForUpdateTests(TransactionTestCase):
         that supports FOR UPDATE but not NOWAIT, then we should find
         that a DatabaseError is raised.
         """
-        self.assertRaises(
-            DatabaseError,
-            list,
-            Person.objects.all().select_for_update(nowait=True)
-        )
+        with self.assertRaises(DatabaseError):
+            list(Person.objects.all().select_for_update(nowait=True))
 
     @skipUnlessDBFeature('has_select_for_update')
     def test_for_update_requires_transaction(self):

tests/select_related/tests.py

@@ -142,11 +142,8 @@ class SelectRelatedTests(TestCase):
             self.assertEqual(s, 'Diptera')
 
     def test_depth_fields_fails(self):
-        self.assertRaises(
-            TypeError,
-            Species.objects.select_related,
-            'genus__family__order', depth=4
-        )
+        with self.assertRaises(TypeError):
+            Species.objects.select_related('genus__family__order', depth=4)
 
     def test_none_clears_list(self):
         queryset = Species.objects.select_related('genus').select_related(None)

tests/serializers/test_yaml.py

@@ -72,11 +72,13 @@ class NoYamlSerializerTestCase(SimpleTestCase):
     def test_serializer_pyyaml_error_message(self):
         """Using yaml serializer without pyyaml raises ImportError"""
         jane = Author(name="Jane")
-        self.assertRaises(ImportError, serializers.serialize, "yaml", [jane])
+        with self.assertRaises(ImportError):
+            serializers.serialize("yaml", [jane])
 
     def test_deserializer_pyyaml_error_message(self):
         """Using yaml deserializer without pyyaml raises ImportError"""
-        self.assertRaises(ImportError, serializers.deserialize, "yaml", "")
+        with self.assertRaises(ImportError):
+            serializers.deserialize("yaml", "")
 
     def test_dumpdata_pyyaml_error_message(self):
         """Calling dumpdata produces an error when yaml package missing"""

tests/sessions_tests/tests.py

@@ -223,7 +223,8 @@ class SessionTestsMixin(object):
     def test_session_key_is_read_only(self):
         def set_session_key(session):
             session.session_key = session._get_new_session_key()
-        self.assertRaises(AttributeError, set_session_key, self.session)
+        with self.assertRaises(AttributeError):
+            set_session_key(self.session)
 
     # Custom session expiry
     def test_default_expiry(self):
@@ -474,7 +475,8 @@ class CacheDBSessionTests(SessionTestsMixin, TestCase):
     @override_settings(SESSION_CACHE_ALIAS='sessions')
     def test_non_default_cache(self):
         # 21000 - CacheDB backend should respect SESSION_CACHE_ALIAS.
-        self.assertRaises(InvalidCacheBackendError, self.backend)
+        with self.assertRaises(InvalidCacheBackendError):
+            self.backend()
 
 
 @override_settings(USE_TZ=True)
@@ -506,20 +508,21 @@ class FileSessionTests(SessionTestsMixin, unittest.TestCase):
     def test_configuration_check(self):
         del self.backend._storage_path
         # Make sure the file backend checks for a good storage dir
-        self.assertRaises(ImproperlyConfigured, self.backend)
+        with self.assertRaises(ImproperlyConfigured):
+            self.backend()
 
     def test_invalid_key_backslash(self):
         # Ensure we don't allow directory-traversal.
         # This is tested directly on _key_to_file, as load() will swallow
         # a SuspiciousOperation in the same way as an IOError - by creating
         # a new session, making it unclear whether the slashes were detected.
-        self.assertRaises(InvalidSessionKey,
-                          self.backend()._key_to_file, "a\\b\\c")
+        with self.assertRaises(InvalidSessionKey):
+            self.backend()._key_to_file("a\\b\\c")
 
     def test_invalid_key_forwardslash(self):
         # Ensure we don't allow directory-traversal
-        self.assertRaises(InvalidSessionKey,
-                          self.backend()._key_to_file, "a/b/c")
+        with self.assertRaises(InvalidSessionKey):
+            self.backend()._key_to_file("a/b/c")
 
     @override_settings(
         SESSION_ENGINE="django.contrib.sessions.backends.file",

tests/settings_tests/tests.py

@@ -179,24 +179,29 @@ class SettingsTests(SimpleTestCase):
         del settings.TEST
 
     def test_override_doesnt_leak(self):
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
         with self.settings(TEST='override'):
             self.assertEqual('override', settings.TEST)
             settings.TEST = 'test'
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
 
     @override_settings(TEST='override')
     def test_decorator(self):
         self.assertEqual('override', settings.TEST)
 
     def test_context_manager(self):
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
         override = override_settings(TEST='override')
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
         override.enable()
         self.assertEqual('override', settings.TEST)
         override.disable()
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
 
     def test_class_decorator(self):
         # SimpleTestCase can be decorated by override_settings, but not ut.TestCase
@@ -215,7 +220,8 @@ class SettingsTests(SimpleTestCase):
             decorated = override_settings(TEST='override')(UnittestTestCaseSubclass)
 
     def test_signal_callback_context_manager(self):
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
         with self.settings(TEST='override'):
             self.assertEqual(self.testvalue, 'override')
         self.assertEqual(self.testvalue, None)
@@ -232,10 +238,12 @@ class SettingsTests(SimpleTestCase):
         settings.TEST = 'test'
         self.assertEqual('test', settings.TEST)
         del settings.TEST
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
 
     def test_settings_delete_wrapped(self):
-        self.assertRaises(TypeError, delattr, settings, '_wrapped')
+        with self.assertRaises(TypeError):
+            delattr(settings, '_wrapped')
 
     def test_override_settings_delete(self):
         """
@@ -245,10 +253,12 @@ class SettingsTests(SimpleTestCase):
         previous_l10n = settings.USE_L10N
         with self.settings(USE_I18N=False):
             del settings.USE_I18N
-            self.assertRaises(AttributeError, getattr, settings, 'USE_I18N')
+            with self.assertRaises(AttributeError):
+                getattr(settings, 'USE_I18N')
             # Should also work for a non-overridden setting
             del settings.USE_L10N
-            self.assertRaises(AttributeError, getattr, settings, 'USE_L10N')
+            with self.assertRaises(AttributeError):
+                getattr(settings, 'USE_L10N')
         self.assertEqual(settings.USE_I18N, previous_i18n)
         self.assertEqual(settings.USE_L10N, previous_l10n)
 
@@ -258,8 +268,10 @@ class SettingsTests(SimpleTestCase):
         runtime, not when it was instantiated.
         """
 
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
-        self.assertRaises(AttributeError, getattr, settings, 'TEST2')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST2')
 
         inner = override_settings(TEST2='override')
         with override_settings(TEST='override'):
@@ -270,10 +282,13 @@ class SettingsTests(SimpleTestCase):
             # inner's __exit__ should have restored the settings of the outer
             # context manager, not those when the class was instantiated
             self.assertEqual('override', settings.TEST)
-            self.assertRaises(AttributeError, getattr, settings, 'TEST2')
+            with self.assertRaises(AttributeError):
+                getattr(settings, 'TEST2')
 
-        self.assertRaises(AttributeError, getattr, settings, 'TEST')
-        self.assertRaises(AttributeError, getattr, settings, 'TEST2')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST')
+        with self.assertRaises(AttributeError):
+            getattr(settings, 'TEST2')
 
 
 class TestComplexSettingOverride(SimpleTestCase):

tests/signed_cookies_tests/tests.py

@@ -25,16 +25,16 @@ class SignedCookieTest(SimpleTestCase):
         request.COOKIES['a'] = response.cookies['a'].value
         value = request.get_signed_cookie('a', salt='one')
         self.assertEqual(value, 'hello')
-        self.assertRaises(signing.BadSignature,
-            request.get_signed_cookie, 'a', salt='two')
+        with self.assertRaises(signing.BadSignature):
+            request.get_signed_cookie('a', salt='two')
 
     def test_detects_tampering(self):
         response = HttpResponse()
         response.set_signed_cookie('c', 'hello')
         request = HttpRequest()
         request.COOKIES['c'] = response.cookies['c'].value[:-2] + '$$'
-        self.assertRaises(signing.BadSignature,
-            request.get_signed_cookie, 'c')
+        with self.assertRaises(signing.BadSignature):
+            request.get_signed_cookie('c')
 
     def test_default_argument_suppresses_exceptions(self):
         response = HttpResponse()
@@ -55,8 +55,8 @@ class SignedCookieTest(SimpleTestCase):
         with freeze_time(123456800):
             self.assertEqual(request.get_signed_cookie('c', max_age=12), value)
             self.assertEqual(request.get_signed_cookie('c', max_age=11), value)
-            self.assertRaises(signing.SignatureExpired,
-                request.get_signed_cookie, 'c', max_age=10)
+            with self.assertRaises(signing.SignatureExpired):
+                request.get_signed_cookie('c', max_age=10)
 
     @override_settings(SECRET_KEY=b'\xe7')
     def test_signed_cookies_with_binary_key(self):

tests/signing/tests.py

@@ -70,8 +70,8 @@ class TestSigner(SimpleTestCase):
         )
         self.assertEqual(value, signer.unsign(signed_value))
         for transform in transforms:
-            self.assertRaises(
-                signing.BadSignature, signer.unsign, transform(signed_value))
+            with self.assertRaises(signing.BadSignature):
+                signer.unsign(transform(signed_value))
 
     def test_dumps_loads(self):
         "dumps and loads be reversible for any JSON serializable object"
@@ -103,8 +103,8 @@ class TestSigner(SimpleTestCase):
         encoded = signing.dumps(value)
         self.assertEqual(value, signing.loads(encoded))
         for transform in transforms:
-            self.assertRaises(
-                signing.BadSignature, signing.loads, transform(encoded))
+            with self.assertRaises(signing.BadSignature):
+                signing.loads(transform(encoded))
 
     def test_works_with_non_ascii_keys(self):
         binary_key = b'\xe7'  # Set some binary (non-ASCII key)
@@ -142,4 +142,5 @@ class TestTimestampSigner(SimpleTestCase):
             self.assertEqual(signer.unsign(ts, max_age=12), value)
             # max_age parameter can also accept a datetime.timedelta object
             self.assertEqual(signer.unsign(ts, max_age=datetime.timedelta(seconds=11)), value)
-            self.assertRaises(signing.SignatureExpired, signer.unsign, ts, max_age=10)
+            with self.assertRaises(signing.SignatureExpired):
+                signer.unsign(ts, max_age=10)

tests/sitemaps_tests/test_http.py

@@ -176,7 +176,8 @@ class HTTPSitemapTests(SitemapTestsBase):
         Sitemap.get_urls and no Site objects exist
         """
         Site.objects.all().delete()
-        self.assertRaises(ImproperlyConfigured, Sitemap().get_urls)
+        with self.assertRaises(ImproperlyConfigured):
+            Sitemap().get_urls()
 
     @modify_settings(INSTALLED_APPS={'remove': 'django.contrib.sites'})
     def test_sitemap_get_urls_no_site_2(self):
@@ -185,7 +186,8 @@ class HTTPSitemapTests(SitemapTestsBase):
         Sitemap.get_urls if Site objects exists, but the sites framework is not
         actually installed.
         """
-        self.assertRaises(ImproperlyConfigured, Sitemap().get_urls)
+        with self.assertRaises(ImproperlyConfigured):
+            Sitemap().get_urls()
 
     def test_sitemap_item(self):
         """

tests/sites_tests/tests.py

@@ -35,7 +35,8 @@ class SitesFrameworkTests(TestCase):
         s = Site.objects.get_current()
         self.assertIsInstance(s, Site)
         s.delete()
-        self.assertRaises(ObjectDoesNotExist, Site.objects.get_current)
+        with self.assertRaises(ObjectDoesNotExist):
+            Site.objects.get_current()
 
     def test_site_cache(self):
         # After updating a Site object (e.g. via the admin), we shouldn't return a
@@ -53,7 +54,8 @@ class SitesFrameworkTests(TestCase):
         # be cleared and get_current() should raise a DoesNotExist.
         self.assertIsInstance(Site.objects.get_current(), Site)
         Site.objects.all().delete()
-        self.assertRaises(Site.DoesNotExist, Site.objects.get_current)
+        with self.assertRaises(Site.DoesNotExist):
+            Site.objects.get_current()
 
     @override_settings(ALLOWED_HOSTS=['example.com'])
     def test_get_current_site(self):
@@ -70,7 +72,8 @@ class SitesFrameworkTests(TestCase):
         # Test that an exception is raised if the sites framework is installed
         # but there is no matching Site
         site.delete()
-        self.assertRaises(ObjectDoesNotExist, get_current_site, request)
+        with self.assertRaises(ObjectDoesNotExist):
+            get_current_site(request)
 
         # A RequestSite is returned if the sites framework is not installed
         with self.modify_settings(INSTALLED_APPS={'remove': 'django.contrib.sites'}):
@@ -112,7 +115,8 @@ class SitesFrameworkTests(TestCase):
 
         # Host header with non-matching domain
         request.META = {'HTTP_HOST': 'example.net'}
-        self.assertRaises(ObjectDoesNotExist, get_current_site, request)
+        with self.assertRaises(ObjectDoesNotExist):
+            get_current_site(request)
 
         # Ensure domain for RequestSite always matches host header
         with self.modify_settings(INSTALLED_APPS={'remove': 'django.contrib.sites'}):
@@ -128,11 +132,14 @@ class SitesFrameworkTests(TestCase):
         # Regression for #17320
         # Domain names are not allowed contain whitespace characters
         site = Site(name="test name", domain="test test")
-        self.assertRaises(ValidationError, site.full_clean)
+        with self.assertRaises(ValidationError):
+            site.full_clean()
         site.domain = "test\ttest"
-        self.assertRaises(ValidationError, site.full_clean)
+        with self.assertRaises(ValidationError):
+            site.full_clean()
         site.domain = "test\ntest"
-        self.assertRaises(ValidationError, site.full_clean)
+        with self.assertRaises(ValidationError):
+            site.full_clean()
 
     def test_clear_site_cache(self):
         request = HttpRequest()