Merge pull request #2144 from 0a69911a/master

Implement collation for queryset

mongoengine/queryset/base.py

@@ -81,6 +81,7 @@ class BaseQuerySet(object):
         self._limit = None
         self._skip = None
         self._hint = -1  # Using -1 as None is a valid value for hint
+        self._collation = None
         self._batch_size = None
         self.only_fields = []
         self._max_time_ms = None
@@ -782,6 +783,7 @@ class BaseQuerySet(object):
             "_limit",
             "_skip",
             "_hint",
+            "_collation",
             "_auto_dereference",
             "_search_text",
             "only_fields",
@@ -864,6 +866,32 @@ class BaseQuerySet(object):
 
         return queryset
 
+    def collation(self, collation=None):
+        """
+        Collation allows users to specify language-specific rules for string
+        comparison, such as rules for lettercase and accent marks.
+        :param collation: `~pymongo.collation.Collation` or dict with
+        following fields:
+            {
+                locale: str,
+                caseLevel: bool,
+                caseFirst: str,
+                strength: int,
+                numericOrdering: bool,
+                alternate: str,
+                maxVariable: str,
+                backwards: str
+            }
+        Collation should be added to indexes like in test example
+        """
+        queryset = self.clone()
+        queryset._collation = collation
+
+        if queryset._cursor_obj:
+            queryset._cursor_obj.collation(collation)
+
+        return queryset
+
     def batch_size(self, size):
         """Limit the number of documents returned in a single batch (each
         batch requires a round trip to the server).
@@ -1640,6 +1668,9 @@ class BaseQuerySet(object):
         if self._hint != -1:
             self._cursor_obj.hint(self._hint)
 
+        if self._collation is not None:
+            self._cursor_obj.collation(self._collation)
+
         if self._batch_size is not None:
             self._cursor_obj.batch_size(self._batch_size)
 

tests/document/test_indexes.py

@@ -3,6 +3,7 @@ import unittest
 from datetime import datetime
 
 from nose.plugins.skip import SkipTest
+from pymongo.collation import Collation
 from pymongo.errors import OperationFailure
 from six import iteritems
 
@@ -536,6 +537,42 @@ class TestIndexes(unittest.TestCase):
         with self.assertRaises(ValueError):
             BlogPost.objects.hint(("tags", 1)).count()
 
+    def test_collation(self):
+        base = {"locale": "en", "strength": 2}
+
+        class BlogPost(Document):
+            name = StringField()
+            meta = {
+                "indexes": [
+                    {"fields": ["name"], "name": "name_index", "collation": base}
+                ]
+            }
+
+        BlogPost.drop_collection()
+
+        names = ["tag1", "Tag2", "tag3", "Tag4", "tag5"]
+        for name in names:
+            BlogPost(name=name).save()
+
+        query_result = BlogPost.objects.collation(base).order_by("name")
+        self.assertEqual(
+            [x.name for x in query_result], sorted(names, key=lambda x: x.lower())
+        )
+        self.assertEqual(5, query_result.count())
+
+        query_result = BlogPost.objects.collation(Collation(**base)).order_by("name")
+        self.assertEqual(
+            [x.name for x in query_result], sorted(names, key=lambda x: x.lower())
+        )
+        self.assertEqual(5, query_result.count())
+
+        incorrect_collation = {"arndom": "wrdo"}
+        with self.assertRaises(OperationFailure):
+            BlogPost.objects.collation(incorrect_collation).count()
+
+        query_result = BlogPost.objects.collation({}).order_by("name")
+        self.assertEqual([x.name for x in query_result], sorted(names))
+
     def test_unique(self):
         """Ensure that uniqueness constraints are applied to fields.
         """