1 files changed, 54 insertions, 0 deletions
diff --git a/tests/postgres_tests/test_json_deprecation.py b/tests/postgres_tests/test_json_deprecation.py
new file mode 100644
index 0000000000..80deb0cb15
--- /dev/null
+++ b/tests/postgres_tests/test_json_deprecation.py
@@ -0,0 +1,54 @@
+try:
+    from django.contrib.postgres.fields import JSONField
+    from django.contrib.postgres.fields.jsonb import KeyTransform, KeyTextTransform
+    from django.contrib.postgres import forms
+except ImportError:
+    pass
+
+from django.core.checks import Warning as DjangoWarning
+from django.utils.deprecation import RemovedInDjango40Warning
+
+from . import PostgreSQLSimpleTestCase
+from .models import PostgreSQLModel
+
+
+class DeprecationTests(PostgreSQLSimpleTestCase):
+    def test_model_field_deprecation_message(self):
+        class PostgreSQLJSONModel(PostgreSQLModel):
+            field = JSONField()
+
+        self.assertEqual(PostgreSQLJSONModel().check(), [
+            DjangoWarning(
+                'django.contrib.postgres.fields.JSONField is deprecated. '
+                'Support for it (except in historical migrations) will be '
+                'removed in Django 4.0.',
+                hint='Use django.db.models.JSONField instead.',
+                obj=PostgreSQLJSONModel._meta.get_field('field'),
+                id='fields.W904',
+            ),
+        ])
+
+    def test_form_field_deprecation_message(self):
+        msg = (
+            'django.contrib.postgres.forms.JSONField is deprecated in favor '
+            'of django.forms.JSONField.'
+        )
+        with self.assertWarnsMessage(RemovedInDjango40Warning, msg):
+            forms.JSONField()
+
+    def test_key_transform_deprecation_message(self):
+        msg = (
+            'django.contrib.postgres.fields.jsonb.KeyTransform is deprecated '
+            'in favor of django.db.models.fields.json.KeyTransform.'
+        )
+        with self.assertWarnsMessage(RemovedInDjango40Warning, msg):
+            KeyTransform('foo', 'bar')
+
+    def test_key_text_transform_deprecation_message(self):
+        msg = (
+            'django.contrib.postgres.fields.jsonb.KeyTextTransform is '
+            'deprecated in favor of '
+            'django.db.models.fields.json.KeyTextTransform.'
+        )
+        with self.assertWarnsMessage(RemovedInDjango40Warning, msg):
+            KeyTextTransform('foo', 'bar')