[fix]validation list field with multi choice values

mongoengine/base/document.py

@@ -1080,5 +1080,9 @@ class BaseDocument(object):
         """Return the display value for a choice field"""
         value = getattr(self, field.name)
         if field.choices and isinstance(field.choices[0], (list, tuple)):
-            return dict(field.choices).get(value, value)
+            sep = getattr(field, 'display_sep', u' ')
+            values = value if field.__name__ == 'ListField' else [value]
+            return sep.join([
+                dict(field.choices).get(val, val)
+                for val in values])
         return value

mongoengine/base/fields.py

@@ -213,7 +213,9 @@ class BaseField(object):
                     )
                 )
         # Choices which are types other than Documents
-        elif value not in choice_list:
+        else:
+            values = value if isinstance(value, (list, tuple)) else [value]
+            if len(set(values) - set(choice_list)):
                 self.error('Value must be one of %s' % six.text_type(choice_list))
 
     def _validate(self, value, **kwargs):

tests/fields/fields.py

@@ -920,6 +920,12 @@ class FieldTest(MongoDBTestCase):
 
     def test_list_validation(self):
         """Ensure that a list field only accepts lists with valid elements."""
+        AccessLevelChoices = (
+            ('a', u'Administrator'),
+            ('b', u'Manager'),
+            ('c', u'Staff'),
+        )
+
         class User(Document):
             pass
 
@@ -932,6 +938,7 @@ class FieldTest(MongoDBTestCase):
             tags = ListField(StringField())
             authors = ListField(ReferenceField(User))
             generic = ListField(GenericReferenceField())
+            access_list = ListField(required=False, default=[], choices=AccessLevelChoices, display_sep=u',')
 
         User.drop_collection()
         BlogPost.drop_collection()
@@ -949,6 +956,17 @@ class FieldTest(MongoDBTestCase):
         post.tags = ('fun', 'leisure')
         post.validate()
 
+        post.access_list = 'a,b'
+        self.assertRaises(ValidationError, post.validate())
+
+        post.access_list = ['c', 'd']
+        self.assertRaises(ValidationError, post.validate())
+
+        post.access_list = ['a', 'b']
+        post.validate()
+
+        self.assertEqual(post.get_access_list_display(), u'Administrator,Manager')
+
         post.comments = ['a']
         self.assertRaises(ValidationError, post.validate)
         post.comments = 'yay'