[1.11.x] Fixed #28702 -- Made query lookups for CIText fields use citext.

Backport of f0a68c25118786d47041d0a435b2afa953be3c86 from master

2 files changed, 7 insertions, 1 deletions

diff --git a/django/contrib/postgres/fields/citext.py b/django/contrib/postgres/fields/citext.py
index 42660001ae..f5ef86c586 100644
--- a/django/contrib/postgres/fields/citext.py
+++ b/django/contrib/postgres/fields/citext.py
@@ -3,7 +3,11 @@ from django.db.models import CharField, EmailField, TextField
 __all__ = ['CICharField', 'CIEmailField', 'CIText', 'CITextField']
 
 
-class CIText:
+class CIText(object):
+
+    def get_internal_type(self):
+        return 'CI' + super(CIText, self).get_internal_type()
+
     def db_type(self, connection):
         return 'citext'
 
diff --git a/django/db/backends/postgresql/operations.py b/django/db/backends/postgresql/operations.py
index a66cb0c563..f220639725 100644
--- a/django/db/backends/postgresql/operations.py
+++ b/django/db/backends/postgresql/operations.py
@@ -83,6 +83,8 @@ class DatabaseOperations(BaseDatabaseOperations):
                            'istartswith', 'endswith', 'iendswith', 'regex', 'iregex'):
             if internal_type in ('IPAddressField', 'GenericIPAddressField'):
                 lookup = "HOST(%s)"
+            elif internal_type in ('CICharField', 'CIEmailField', 'CITextField'):
+                lookup = '%s::citext'
             else:
                 lookup = "%s::text"