Fixed #21332, #26538 -- Fixed inconsistent and duplicate form fields on inline formsets.

1 files changed, 7 insertions, 7 deletions

diff --git a/django/forms/models.py b/django/forms/models.py
index 4ed8b746d9..7ba98e1e26 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -889,6 +889,13 @@ class BaseInlineFormSet(BaseModelFormSet):
         super(BaseInlineFormSet, self).__init__(data, files, prefix=prefix,
                                                 queryset=qs, **kwargs)
 
+        # Add the generated field to form._meta.fields if it's defined to make
+        # sure validation isn't skipped on that field.
+        if self.form._meta.fields and self.fk.name not in self.form._meta.fields:
+            if isinstance(self.form._meta.fields, tuple):
+                self.form._meta.fields = list(self.form._meta.fields)
+            self.form._meta.fields.append(self.fk.name)
+
     def initial_form_count(self):
         if self.save_as_new:
             return 0
@@ -960,13 +967,6 @@ class BaseInlineFormSet(BaseModelFormSet):
 
         form.fields[name] = InlineForeignKeyField(self.instance, **kwargs)
 
-        # Add the generated field to form._meta.fields if it's defined to make
-        # sure validation isn't skipped on that field.
-        if form._meta.fields:
-            if isinstance(form._meta.fields, tuple):
-                form._meta.fields = list(form._meta.fields)
-            form._meta.fields.append(self.fk.name)
-
     def get_unique_error_message(self, unique_check):
         unique_check = [field for field in unique_check if field != self.fk.name]
         return super(BaseInlineFormSet, self).get_unique_error_message(unique_check)