Fixed #6302. FileField no longer requires a value if one already exists. Thanks Brian Rosner and Øyvind Saltvik.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@7021 bcc190cf-cafb-0310-a4f2-bffc1f526a37

3 files changed, 17 insertions, 7 deletions

diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index 139a096b68..f78c81ae39 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -797,13 +797,17 @@ class FileField(Field):
         return os.path.normpath(f)
 
     def save_form_data(self, instance, data):
-        if data:
+        from django.newforms.fields import UploadedFile
+        if data and isinstance(data, UploadedFile):
             getattr(instance, "save_%s_file" % self.name)(data.filename, data.content, save=False)
 
     def formfield(self, **kwargs):
         defaults = {'form_class': forms.FileField}
         # If a file has been provided previously, then the form doesn't require
         # that a new file is provided this time.
+        # The code to mark the form field as not required is used by
+        # form_for_instance, but can probably be removed once form_for_instance
+        # is gone. ModelForm uses a different method to check for an existing file.
         if 'initial' in kwargs:
             defaults['required'] = False
         defaults.update(kwargs)
diff --git a/django/newforms/fields.py b/django/newforms/fields.py
index 3b8f4195b0..0761b8f2af 100644
--- a/django/newforms/fields.py
+++ b/django/newforms/fields.py
@@ -437,10 +437,12 @@ class FileField(Field):
     def __init__(self, *args, **kwargs):
         super(FileField, self).__init__(*args, **kwargs)
 
-    def clean(self, data):
-        super(FileField, self).clean(data)
+    def clean(self, data, initial=None):
+        super(FileField, self).clean(initial or data)
         if not self.required and data in EMPTY_VALUES:
             return None
+        elif not data and initial:
+            return initial
         try:
             f = UploadedFile(data['filename'], data['content'])
         except TypeError:
@@ -456,12 +458,12 @@ class ImageField(FileField):
         'invalid_image': _(u"Upload a valid image. The file you uploaded was either not an image or a corrupted image."),
     }
 
-    def clean(self, data):
+    def clean(self, data, initial=None):
         """
         Checks that the file-upload field data contains a valid image (GIF, JPG,
         PNG, possibly others -- whatever the Python Imaging Library supports).
         """
-        f = super(ImageField, self).clean(data)
+        f = super(ImageField, self).clean(data, initial)
         if f is None:
             return None
         from PIL import Image
diff --git a/django/newforms/forms.py b/django/newforms/forms.py
index 556c00a777..04bf62e445 100644
--- a/django/newforms/forms.py
+++ b/django/newforms/forms.py
@@ -9,7 +9,7 @@ from django.utils.html import escape
 from django.utils.encoding import StrAndUnicode, smart_unicode, force_unicode
 from django.utils.safestring import mark_safe
 
-from fields import Field
+from fields import Field, FileField
 from widgets import TextInput, Textarea
 from util import flatatt, ErrorDict, ErrorList, ValidationError
 
@@ -182,7 +182,11 @@ class BaseForm(StrAndUnicode):
             # widgets split data over several HTML fields.
             value = field.widget.value_from_datadict(self.data, self.files, self.add_prefix(name))
             try:
-                value = field.clean(value)
+                if isinstance(field, FileField):
+                    initial = self.initial.get(name, field.initial)
+                    value = field.clean(value, initial)
+                else:
+                    value = field.clean(value)
                 self.cleaned_data[name] = value
                 if hasattr(self, 'clean_%s' % name):
                     value = getattr(self, 'clean_%s' % name)()