5 files changed, 61 insertions, 10 deletions
diff --git a/tests/postgres_tests/fields.py b/tests/postgres_tests/fields.py
index c02bc2faf4..14283ccd61 100644
--- a/tests/postgres_tests/fields.py
+++ b/tests/postgres_tests/fields.py
@@ -6,8 +6,9 @@ from django.db import models
 
 try:
     from django.contrib.postgres.fields import (
-        ArrayField, BigIntegerRangeField, DateRangeField, DateTimeRangeField,
-        FloatRangeField, HStoreField, IntegerRangeField, JSONField,
+        ArrayField, BigIntegerRangeField, CITextField, DateRangeField,
+        DateTimeRangeField, FloatRangeField, HStoreField, IntegerRangeField,
+        JSONField,
     )
     from django.contrib.postgres.search import SearchVectorField
 except ImportError:
@@ -29,6 +30,7 @@ except ImportError:
 
     ArrayField = DummyArrayField
     BigIntegerRangeField = models.Field
+    CITextField = models.Field
     DateRangeField = models.Field
     DateTimeRangeField = models.Field
     FloatRangeField = models.Field
diff --git a/tests/postgres_tests/migrations/0001_setup_extensions.py b/tests/postgres_tests/migrations/0001_setup_extensions.py
index a32319b911..41628030b7 100644
--- a/tests/postgres_tests/migrations/0001_setup_extensions.py
+++ b/tests/postgres_tests/migrations/0001_setup_extensions.py
@@ -5,8 +5,8 @@ from django.db import migrations
 
 try:
     from django.contrib.postgres.operations import (
-        BtreeGinExtension, CreateExtension, HStoreExtension, TrigramExtension,
-        UnaccentExtension,
+        BtreeGinExtension, CITextExtension, CreateExtension, HStoreExtension,
+        TrigramExtension, UnaccentExtension,
     )
 except ImportError:
     from django.test import mock
@@ -15,6 +15,7 @@ except ImportError:
     HStoreExtension = mock.Mock()
     TrigramExtension = mock.Mock()
     UnaccentExtension = mock.Mock()
+    CITextExtension = mock.Mock()
 
 
 class Migration(migrations.Migration):
@@ -27,4 +28,5 @@ class Migration(migrations.Migration):
         HStoreExtension(),
         TrigramExtension(),
         UnaccentExtension(),
+        CITextExtension(),
     ]
diff --git a/tests/postgres_tests/migrations/0002_create_test_models.py b/tests/postgres_tests/migrations/0002_create_test_models.py
index 161f883d3f..8f72183f5c 100644
--- a/tests/postgres_tests/migrations/0002_create_test_models.py
+++ b/tests/postgres_tests/migrations/0002_create_test_models.py
@@ -5,9 +5,9 @@ from django.core.serializers.json import DjangoJSONEncoder
 from django.db import migrations, models
 
 from ..fields import (
-    ArrayField, BigIntegerRangeField, DateRangeField, DateTimeRangeField,
-    FloatRangeField, HStoreField, IntegerRangeField, JSONField,
-    SearchVectorField,
+    ArrayField, BigIntegerRangeField, CITextField, DateRangeField,
+    DateTimeRangeField, FloatRangeField, HStoreField, IntegerRangeField,
+    JSONField, SearchVectorField,
 )
 from ..models import TagField
 
@@ -139,6 +139,16 @@ class Migration(migrations.Migration):
             bases=None,
         ),
         migrations.CreateModel(
+            name='CITextTestModel',
+            fields=[
+                ('name', CITextField(primary_key=True, max_length=255)),
+            ],
+            options={
+                'required_db_vendor': 'postgresql',
+            },
+            bases=None,
+        ),
+        migrations.CreateModel(
             name='Line',
             fields=[
                 ('id', models.AutoField(verbose_name='ID', serialize=False, auto_created=True, primary_key=True)),
diff --git a/tests/postgres_tests/models.py b/tests/postgres_tests/models.py
index 8913e60869..9687a874c0 100644
--- a/tests/postgres_tests/models.py
+++ b/tests/postgres_tests/models.py
@@ -2,9 +2,9 @@ from django.core.serializers.json import DjangoJSONEncoder
 from django.db import models
 
 from .fields import (
-    ArrayField, BigIntegerRangeField, DateRangeField, DateTimeRangeField,
-    FloatRangeField, HStoreField, IntegerRangeField, JSONField,
-    SearchVectorField,
+    ArrayField, BigIntegerRangeField, CITextField, DateRangeField,
+    DateTimeRangeField, FloatRangeField, HStoreField, IntegerRangeField,
+    JSONField, SearchVectorField,
 )
 
 
@@ -101,6 +101,13 @@ class Character(models.Model):
         return self.name
 
 
+class CITextTestModel(PostgreSQLModel):
+    name = CITextField(primary_key=True, max_length=255)
+
+    def __str__(self):
+        return self.name
+
+
 class Line(PostgreSQLModel):
     scene = models.ForeignKey('Scene', models.CASCADE)
     character = models.ForeignKey('Character', models.CASCADE)
diff --git a/tests/postgres_tests/test_citext.py b/tests/postgres_tests/test_citext.py
new file mode 100644
index 0000000000..7f86f6a205
--- /dev/null
+++ b/tests/postgres_tests/test_citext.py
@@ -0,0 +1,30 @@
+"""
+The citext PostgreSQL extension supports indexing of case-insensitive text
+strings and thus eliminates the need for operations such as iexact and other
+modifiers to enforce use of an index.
+"""
+from django.db import IntegrityError
+
+from . import PostgreSQLTestCase
+from .models import CITextTestModel
+
+
+class CITextTestCase(PostgreSQLTestCase):
+
+    @classmethod
+    def setUpTestData(cls):
+        CITextTestModel.objects.create(name='JoHn')
+
+    def test_equal_lowercase(self):
+        """
+        citext removes the need for iexact as the index is case-insensitive.
+        """
+        self.assertEqual(CITextTestModel.objects.filter(name='john').count(), 1)
+
+    def test_fail_case(self):
+        """
+        Creating an entry for a citext-field which clashes with an existing
+        value isn't allowed.
+        """
+        with self.assertRaises(IntegrityError):
+            CITextTestModel.objects.create(name='John')