django/tests/db_functions/math/test_power.py

45 lines
1.7 KiB
Python

from decimal import Decimal
from django.db.models.functions import Power
from django.test import TestCase
from ..models import DecimalModel, FloatModel, IntegerModel
class PowerTests(TestCase):
def test_null(self):
IntegerModel.objects.create(big=100)
obj = IntegerModel.objects.annotate(
null_power_small=Power('small', 'normal'),
null_power_normal=Power('normal', 'big'),
).first()
self.assertIsNone(obj.null_power_small)
self.assertIsNone(obj.null_power_normal)
def test_decimal(self):
DecimalModel.objects.create(n1=Decimal('1.0'), n2=Decimal('-0.6'))
obj = DecimalModel.objects.annotate(n_power=Power('n1', 'n2')).first()
self.assertIsInstance(obj.n_power, Decimal)
self.assertAlmostEqual(obj.n_power, Decimal(obj.n1 ** obj.n2))
def test_float(self):
FloatModel.objects.create(f1=2.3, f2=1.1)
obj = FloatModel.objects.annotate(f_power=Power('f1', 'f2')).first()
self.assertIsInstance(obj.f_power, float)
self.assertAlmostEqual(obj.f_power, obj.f1 ** obj.f2)
def test_integer(self):
IntegerModel.objects.create(small=-1, normal=20, big=3)
obj = IntegerModel.objects.annotate(
small_power=Power('small', 'normal'),
normal_power=Power('normal', 'big'),
big_power=Power('big', 'small'),
).first()
self.assertIsInstance(obj.small_power, float)
self.assertIsInstance(obj.normal_power, float)
self.assertIsInstance(obj.big_power, float)
self.assertAlmostEqual(obj.small_power, obj.small ** obj.normal)
self.assertAlmostEqual(obj.normal_power, obj.normal ** obj.big)
self.assertAlmostEqual(obj.big_power, obj.big ** obj.small)