Inject base class in favor of separate new metho

Author: codingjoe

s3file/apps.py

@@ -11,7 +11,8 @@ def ready(self):
 
         if isinstance(default_storage, S3Boto3Storage):
             from django import forms
-            from .forms import S3FileInput
+            from .forms import S3FileInputMixin
 
-            forms.ClearableFileInput.__new__ = \
-                lambda cls, *args, **kwargs: object.__new__(S3FileInput)
+            if S3FileInputMixin not in forms.ClearableFileInput.__bases__:
+                forms.ClearableFileInput.__bases__ = \
+                    (S3FileInputMixin,) + forms.ClearableFileInput.__bases__

s3file/forms.py

@@ -10,7 +10,7 @@
 logger = logging.getLogger('s3file')
 
 
-class S3FileInput(ClearableFileInput):
+class S3FileInputMixin:
     """FileInput that uses JavaScript to directly upload to Amazon S3."""
 
     needs_multipart_form = False
@@ -26,7 +26,7 @@ def client(self):
         return default_storage.connection.meta.client
 
     def build_attrs(self, *args, **kwargs):
-        attrs = super(S3FileInput, self).build_attrs(*args, **kwargs)
+        attrs = super().build_attrs(*args, **kwargs)
 
         mime_type = attrs.get('accept', None)
         response = self.client.generate_presigned_post(
@@ -75,5 +75,4 @@ def upload_folder(self):
     class Media:
         js = (
             's3file/js/s3file.js',
-
         )

setup.py

@@ -3,7 +3,7 @@
 
 setup(
     name='django-s3file',
-    version='3.0.0',
+    version='3.0.1',
     description='A lightweight file uploader input for Django and Amazon S3',
     author='codingjoe',
     url='https://github.com/codingjoe/django-s3file',

tests/test_apps.py

@@ -3,14 +3,14 @@
 from django import forms
 
 from s3file.apps import S3FileConfig
-from s3file.forms import S3FileInput
+from s3file.forms import S3FileInputMixin
 
 
 class TestS3FileConfig:
     def test_ready(self, settings):
         app = S3FileConfig('s3file', importlib.import_module('tests.testapp'))
         app.ready()
-        assert not isinstance(forms.ClearableFileInput(), S3FileInput)
+        assert not isinstance(forms.ClearableFileInput(), S3FileInputMixin)
         settings.DEFAULT_FILE_STORAGE = 'storages.backends.s3boto3.S3Boto3Storage'
         app.ready()
-        assert isinstance(forms.ClearableFileInput(), S3FileInput)
+        assert isinstance(forms.ClearableFileInput(), S3FileInputMixin)

tests/test_forms.py

@@ -7,7 +7,7 @@
 from selenium.webdriver.support.expected_conditions import staleness_of
 from selenium.webdriver.support.wait import WebDriverWait
 
-from s3file.forms import S3FileInput
+from s3file.forms import S3FileInputMixin
 from tests.testapp.forms import UploadForm
 
 try:
@@ -33,13 +33,15 @@ def url(self):
 
     @pytest.fixture(autouse=True)
     def patch(self):
-        ClearableFileInput.__new__ = \
-            lambda cls, *args, **kwargs: object.__new__(S3FileInput)
+        if S3FileInputMixin not in ClearableFileInput.__bases__:
+            ClearableFileInput.__bases__ = \
+                (S3FileInputMixin,) + ClearableFileInput.__bases__
+        pass
 
     @pytest.fixture
     def freeze(self, monkeypatch):
         """Freeze datetime and UUID."""
-        monkeypatch.setattr('s3file.forms.S3FileInput.upload_folder', 'tmp')
+        monkeypatch.setattr('s3file.forms.S3FileInputMixin.upload_folder', 'tmp')
 
     def test_value_from_datadict(self, client, upload_file):
         with open(upload_file) as f:
@@ -78,7 +80,7 @@ def test_clear(self, filemodel):
         assert not form.cleaned_data['file']
 
     def test_build_attr(self):
-        assert set(S3FileInput().build_attrs({}).keys()) == {
+        assert set(ClearableFileInput().build_attrs({}).keys()) == {
             'class',
             'data-url',
             'data-fields-x-amz-algorithm',
@@ -88,11 +90,12 @@ def test_build_attr(self):
             'data-fields-policy',
             'data-fields-key',
         }
-        assert S3FileInput().build_attrs({})['class'] == 's3file'
-        assert S3FileInput().build_attrs({'class': 'my-class'})['class'] == 'my-class s3file'
+        assert ClearableFileInput().build_attrs({})['class'] == 's3file'
+        assert ClearableFileInput().build_attrs(
+            {'class': 'my-class'})['class'] == 'my-class s3file'
 
     def test_get_conditions(self, freeze):
-        conditions = S3FileInput().get_conditions(None)
+        conditions = ClearableFileInput().get_conditions(None)
         assert all(condition in conditions for condition in [
             {"bucket": 'test-bucket'},
             {"success_action_status": "201"},
@@ -101,15 +104,15 @@ def test_get_conditions(self, freeze):
         ]), conditions
 
     def test_accept(self):
-        widget = S3FileInput()
+        widget = ClearableFileInput()
         assert 'accept' not in widget.render(name='file', value='test.jpg')
         assert ["starts-with", "$Content-Type", ""] in widget.get_conditions(None)
 
-        widget = S3FileInput(attrs={'accept': 'image/*'})
+        widget = ClearableFileInput(attrs={'accept': 'image/*'})
         assert 'accept="image/*"' in widget.render(name='file', value='test.jpg')
         assert ["starts-with", "$Content-Type", "image/"] in widget.get_conditions('image/*')
 
-        widget = S3FileInput(attrs={'accept': 'image/jpeg'})
+        widget = ClearableFileInput(attrs={'accept': 'image/jpeg'})
         assert 'accept="image/jpeg"' in widget.render(name='file', value='test.jpg')
         assert {"Content-Type": 'image/jpeg'} in widget.get_conditions('image/jpeg')