From e07609a0d1cac573890380ee32b85d7743632650 Mon Sep 17 00:00:00 2001
From: Mariusz Felisiak <felisiak.mariusz@gmail.com>
Date: Tue, 22 Jun 2021 06:10:54 +0200
Subject: [PATCH] Refs #32858, Refs #32392 -- Restored using :: shortcut syntax
in Cast() on PostgreSQL.
This partly reverts commit fdfbc66331292def201c9344e3cd29fbcbcd076a
unnecessary since b69b0c3fe871167a0ca01bb439508e335143801f.
---
django/db/models/functions/comparison.py | 6 ++++++
tests/db_functions/comparison/test_cast.py | 17 +++++++++++++++++
tests/postgres_tests/test_indexes.py | 2 +-
3 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/django/db/models/functions/comparison.py b/django/db/models/functions/comparison.py
index 2976985db8..8a1c34430b 100644
--- a/django/db/models/functions/comparison.py
+++ b/django/db/models/functions/comparison.py
@@ -42,6 +42,12 @@ class Cast(Func):
template = "JSON_EXTRACT(%(expressions)s, '$')"
return self.as_sql(compiler, connection, template=template, **extra_context)
+ def as_postgresql(self, compiler, connection, **extra_context):
+ # CAST would be valid too, but the :: shortcut syntax is more readable.
+ # 'expressions' is wrapped in parentheses in case it's a complex
+ # expression.
+ return self.as_sql(compiler, connection, template='(%(expressions)s)::%(db_type)s', **extra_context)
+
def as_oracle(self, compiler, connection, **extra_context):
if self.output_field.get_internal_type() == 'JSONField':
# Oracle doesn't support explicit cast to JSON.
diff --git a/tests/db_functions/comparison/test_cast.py b/tests/db_functions/comparison/test_cast.py
index 687cf77656..ffba8af316 100644
--- a/tests/db_functions/comparison/test_cast.py
+++ b/tests/db_functions/comparison/test_cast.py
@@ -1,9 +1,11 @@
import datetime
import decimal
+import unittest
from django.db import connection, models
from django.db.models.functions import Cast
from django.test import TestCase, ignore_warnings, skipUnlessDBFeature
+from django.test.utils import CaptureQueriesContext
from ..models import Author, DTModel, Fan, FloatModel
@@ -125,5 +127,20 @@ class CastTests(TestCase):
self.assertIsInstance(cast_float, float)
self.assertEqual(cast_float, 0.125)
+ @unittest.skipUnless(connection.vendor == 'postgresql', 'PostgreSQL test')
+ def test_expression_wrapped_with_parentheses_on_postgresql(self):
+ """
+ The SQL for the Cast expression is wrapped with parentheses in case
+ it's a complex expression.
+ """
+ with CaptureQueriesContext(connection) as captured_queries:
+ list(Author.objects.annotate(
+ cast_float=Cast(models.Avg('age'), models.FloatField()),
+ ))
+ self.assertIn(
+ '(AVG("db_functions_author"."age"))::double precision',
+ captured_queries[0]['sql'],
+ )
+
def test_cast_to_text_field(self):
self.assertEqual(Author.objects.values_list(Cast('age', models.TextField()), flat=True).get(), '1')
diff --git a/tests/postgres_tests/test_indexes.py b/tests/postgres_tests/test_indexes.py
index 3578fb68f3..a212de2087 100644
--- a/tests/postgres_tests/test_indexes.py
+++ b/tests/postgres_tests/test_indexes.py
@@ -305,7 +305,7 @@ class SchemaTests(PostgreSQLTestCase):
self.assertIn(index_name, constraints)
self.assertIn(constraints[index_name]['type'], GinIndex.suffix)
self.assertIs(sql.references_column(table, 'field'), True)
- self.assertIn(' AS tsvector', str(sql))
+ self.assertIn('::tsvector', str(sql))
with connection.schema_editor() as editor:
editor.remove_index(TextFieldModel, index)
self.assertNotIn(index_name, self.get_constraints(table))