[1.11.x] Fixed #28387 -- Fixed has_changed() for disabled form fields that subclass it.

Backport of 5debbdfcc84266703191e084914998e38f5f52eb from master

2 files changed, 12 insertions, 0 deletions

diff --git a/django/forms/fields.py b/django/forms/fields.py
index 33ed2882a3..f2b5b77185 100644
--- a/django/forms/fields.py
+++ b/django/forms/fields.py
@@ -604,6 +604,8 @@ class FileField(Field):
         return data
 
     def has_changed(self, initial, data):
+        if self.disabled:
+            return False
         if data is None:
             return False
         return True
@@ -724,6 +726,8 @@ class BooleanField(Field):
             raise ValidationError(self.error_messages['required'], code='required')
 
     def has_changed(self, initial, data):
+        if self.disabled:
+            return False
         # Sometimes data or initial may be a string equivalent of a boolean
         # so we should run it through to_python first to get a boolean value
         return self.to_python(initial) != self.to_python(data)
@@ -891,6 +895,8 @@ class MultipleChoiceField(ChoiceField):
                 )
 
     def has_changed(self, initial, data):
+        if self.disabled:
+            return False
         if initial is None:
             initial = []
         if data is None:
@@ -1069,6 +1075,8 @@ class MultiValueField(Field):
         raise NotImplementedError('Subclasses must implement this method.')
 
     def has_changed(self, initial, data):
+        if self.disabled:
+            return False
         if initial is None:
             initial = ['' for x in range(0, len(data))]
         else:
diff --git a/django/forms/models.py b/django/forms/models.py
index 132e4255bb..db710a2ed2 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -1244,6 +1244,8 @@ class ModelChoiceField(ChoiceField):
         return Field.validate(self, value)
 
     def has_changed(self, initial, data):
+        if self.disabled:
+            return False
         initial_value = initial if initial is not None else ''
         data_value = data if data is not None else ''
         return force_text(self.prepare_value(initial_value)) != force_text(data_value)
@@ -1331,6 +1333,8 @@ class ModelMultipleChoiceField(ModelChoiceField):
         return super(ModelMultipleChoiceField, self).prepare_value(value)
 
     def has_changed(self, initial, data):
+        if self.disabled:
+            return False
         if initial is None:
             initial = []
         if data is None: