Fixed #17027 -- Added support for the power operator in F expressions.

Thanks dan at dlo.me for the initial patch.

- Added __pow__ and __rpow__ to ExpressionNode
- Added oracle and mysql specific power expressions
- Added used-defined power function for sqlite

2 files changed, 15 insertions, 1 deletions

diff --git a/tests/expressions_regress/models.py b/tests/expressions_regress/models.py
index 4679dcd567..bd3e52f54d 100644
--- a/tests/expressions_regress/models.py
+++ b/tests/expressions_regress/models.py
@@ -8,7 +8,7 @@ from django.db import models
 
 @python_2_unicode_compatible
 class Number(models.Model):
-    integer = models.IntegerField(db_column='the_integer')
+    integer = models.BigIntegerField(db_column='the_integer')
     float = models.FloatField(null=True, db_column='the_float')
 
     def __str__(self):
diff --git a/tests/expressions_regress/tests.py b/tests/expressions_regress/tests.py
index 6d96e0cd7e..470ab7c8e5 100644
--- a/tests/expressions_regress/tests.py
+++ b/tests/expressions_regress/tests.py
@@ -145,6 +145,13 @@ class ExpressionOperatorTests(TestCase):
         self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 58)
         self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(15.500, places=3))
 
+    def test_lefthand_power(self):
+        # LH Powert arithmetic operation on floats and integers
+        Number.objects.filter(pk=self.n.pk).update(integer=F('integer') ** 2,
+                                                float=F('float') ** 1.5)
+        self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 1764)
+        self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(61.02, places=2))
+
     def test_right_hand_addition(self):
         # Right hand operators
         Number.objects.filter(pk=self.n.pk).update(integer=15 + F('integer'),
@@ -185,6 +192,13 @@ class ExpressionOperatorTests(TestCase):
         self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 27)
         self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(15.500, places=3))
 
+    def test_righthand_power(self):
+        # RH Powert arithmetic operation on floats and integers
+        Number.objects.filter(pk=self.n.pk).update(integer=2 ** F('integer'),
+                                                float=1.5 ** F('float'))
+        self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 4398046511104)
+        self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(536.308, places=3))
+
 
 class FTimeDeltaTests(TestCase):