Avoid over-explaining in comments.

Co-authored-by: Adam Johnson <[email protected]>

Fix tests.

django/db/models/fields/files.py

@@ -91,14 +91,10 @@ def open(self, mode="rb"):
  def save(self, name, content, save=True):
  name = self.field.generate_filename(self.instance, name)
  self.name = self.storage.save(name, content, max_length=self.field.max_length)
-
- # Set the file-like content using the descriptors __set__ method.
  setattr(self.instance, self.field.attname, content)
-
- # Update the name in case generate_filename or the storage backend
- # changed the name. Avoids re-running the descriptor logic.
+ # Update the name in case generate_filename() or storage.save() changed
+ # it, but bypass the descriptor to avoid re-reading the file.
  self.instance.__dict__[self.field.attname] = self.name
-
  self._committed = True
 
  # Save the object because it has changed, unless save is False

tests/model_fields/storage.py

@@ -1,10 +1,6 @@
 from django.core.files.storage.filesystem import FileSystemStorage
 
 
-class NoReadException(Exception):
- pass
-
-
 class NoReadFileSystemStorage(FileSystemStorage):
  def open(self, *args, **kwargs):
- raise NoReadException("This storage class does not support reading.")
+ raise AssertionError("This storage class does not support reading.")

tests/model_fields/test_imagefield.py

@@ -474,10 +474,8 @@ def test_dimensions(self):
 
 @skipIf(Image is None, "Pillow is required to test ImageField")
 class NoReadTests(ImageFieldTestMixin, TestCase):
- PersonNoReadImage = PersonNoReadImage
-
  def test_width_height_correct_name_mangling_correct(self):
- instance1 = self.PersonNoReadImage()
+ instance1 = PersonNoReadImage()
 
  instance1.mugshot.save("mug", self.file1)
 
@@ -489,7 +487,7 @@ def test_width_height_correct_name_mangling_correct(self):
  self.assertEqual(instance1.mugshot_width, 4)
  self.assertEqual(instance1.mugshot_height, 8)
 
- instance2 = self.PersonNoReadImage()
+ instance2 = PersonNoReadImage()
  instance2.mugshot.save("mug", self.file1)
  instance2.save()