Fixed #7885 -- Prevent duplicates in fields and fieldsets declarations. Thanks julien and wamberg for the patches.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@8173 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/admin/validation.py

@@ -1,3 +1,7 @@
+try:
+    set
+except NameError:
+    from sets import Set as set   # Python 2.3 fallback
 
 from django.core.exceptions import ImproperlyConfigured
 from django.db import models
@@ -165,6 +169,8 @@ def _validate_base(cls, model):
             _check_form_field_existsw('fields', field)
         if cls.fieldsets:
             raise ImproperlyConfigured('Both fieldsets and fields are specified in %s.' % cls.__name__)
+        if len(cls.fields) > len(set(cls.fields)):
+            raise ImproperlyConfigured('There are duplicate field(s) in %s.fields' % cls.__name__)
 
     # fieldsets
     if cls.fieldsets: # default value is None
@@ -179,7 +185,10 @@ def _validate_base(cls, model):
                 raise ImproperlyConfigured("`fields` key is required in "
                         "%s.fieldsets[%d][1] field options dict."
                         % (cls.__name__, idx))
-        for field in flatten_fieldsets(cls.fieldsets):
+        flattened_fieldsets = flatten_fieldsets(cls.fieldsets)
+        if len(flattened_fieldsets) > len(set(flattened_fieldsets)):
+            raise ImproperlyConfigured('There are duplicate field(s) in %s.fieldsets' % cls.__name__)
+        for field in flattened_fieldsets:
             _check_form_field_existsw("fieldsets[%d][1]['fields']" % idx, field)
 
     # form

tests/regressiontests/modeladmin/models.py

@@ -346,6 +346,20 @@ Traceback (most recent call last):
 ...
 ImproperlyConfigured: Both fieldsets and fields are specified in ValidationTestModelAdmin.
 
+>>> class ValidationTestModelAdmin(ModelAdmin): 
+...     fieldsets = [(None, {'fields': ['name', 'name']})] 
+>>> validate(ValidationTestModelAdmin, ValidationTestModel) 
+Traceback (most recent call last): 
+... 
+ImproperlyConfigured: There are duplicate field(s) in ValidationTestModelAdmin.fieldsets
+
+>>> class ValidationTestModelAdmin(ModelAdmin):
+...     fields = ["name", "name"]
+>>> validate(ValidationTestModelAdmin, ValidationTestModel)
+Traceback (most recent call last):
+...
+ImproperlyConfigured: There are duplicate field(s) in ValidationTestModelAdmin.fields
+
 # form
 
 >>> class FakeForm(object):