Ticket #12237: 12237-m2m-through-modeladmin-fieldsets.diff

django/contrib/admin/validation.py

@@ -222 +222 @@
             raise ImproperlyConfigured('There are duplicate field(s) in %s.fieldsets' % cls.__name__)
         for field in flattened_fieldsets:
             check_formfield(cls, model, opts, "fieldsets[%d][1]['fields']" % idx, field)
+            try:
+                f = opts.get_field(field)
+            except models.FieldDoesNotExist:
+                continue
+            if isinstance(f, models.ManyToManyField) and not f.rel.through._meta.auto_created:
+                raise ImproperlyConfigured("'%s.fieldsets' can't include the ManyToManyField field '%s' because '%s' manually specifies a 'through' model." % (cls.__name__, field, field))
 
     # form
     if hasattr(cls, 'form') and not issubclass(cls.form, BaseModelForm):

tests/regressiontests/admin_validation/models.py

@@ -108 +108 @@
 
 >>> validate_inline(TwoAlbumFKAndAnEInline, None, Album)
 
-# Regression test for #12203 - Fail more gracefully when a M2M field that
-# specifies the 'through' option is included in the 'fields' ModelAdmin option.
+# Regression test for #12203/#12237 - Fail more gracefully when a M2M field that
+# specifies the 'through' option is included in the 'fields'  or the 'fieldsets'
+# ModelAdmin options.
 
 >>> class BookAdmin(admin.ModelAdmin):
 ...     fields = ['authors']
@@ -118 +119 @@
 Traceback (most recent call last):
     ...
 ImproperlyConfigured: 'BookAdmin.fields' can't include the ManyToManyField field 'authors' because 'authors' manually specifies a 'through' model.
+
+>>> class FieldsetBookAdmin(admin.ModelAdmin):
+...     fieldsets = (
+...         ('Header 1', {'fields': ('name',)}),
+...         ('Header 2', {'fields': ('authors',)}),
+...     )
+
+>>> validate(FieldsetBookAdmin, Book)
+Traceback (most recent call last):
+   ...
+ImproperlyConfigured: 'FieldsetBookAdmin.fieldsets' can't include the ManyToManyField field 'authors' because 'authors' manually specifies a 'through' model.
 
 # Regression test for #12209 -- If the explicitly provided through model
 # is specified as a string, the admin should still be able use