django/tests/expressions/tests.py

702 lines
27 KiB
Python

from __future__ import unicode_literals
from copy import deepcopy
import datetime
from django.core.exceptions import FieldError
from django.db import connection
from django.db.models import F
from django.db import transaction
from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature
from django.test.utils import Approximate
from django.utils import six
from .models import Company, Employee, Number, Experiment
class ExpressionsTests(TestCase):
def test_filter(self):
Company.objects.create(
name="Example Inc.", num_employees=2300, num_chairs=5,
ceo=Employee.objects.create(firstname="Joe", lastname="Smith")
)
Company.objects.create(
name="Foobar Ltd.", num_employees=3, num_chairs=4,
ceo=Employee.objects.create(firstname="Frank", lastname="Meyer")
)
Company.objects.create(
name="Test GmbH", num_employees=32, num_chairs=1,
ceo=Employee.objects.create(firstname="Max", lastname="Mustermann")
)
company_query = Company.objects.values(
"name", "num_employees", "num_chairs"
).order_by(
"name", "num_employees", "num_chairs"
)
# We can filter for companies where the number of employees is greater
# than the number of chairs.
self.assertQuerysetEqual(
company_query.filter(num_employees__gt=F("num_chairs")), [
{
"num_chairs": 5,
"name": "Example Inc.",
"num_employees": 2300,
},
{
"num_chairs": 1,
"name": "Test GmbH",
"num_employees": 32
},
],
lambda o: o
)
# We can set one field to have the value of another field
# Make sure we have enough chairs
company_query.update(num_chairs=F("num_employees"))
self.assertQuerysetEqual(
company_query, [
{
"num_chairs": 2300,
"name": "Example Inc.",
"num_employees": 2300
},
{
"num_chairs": 3,
"name": "Foobar Ltd.",
"num_employees": 3
},
{
"num_chairs": 32,
"name": "Test GmbH",
"num_employees": 32
}
],
lambda o: o
)
# We can perform arithmetic operations in expressions
# Make sure we have 2 spare chairs
company_query.update(num_chairs=F("num_employees") + 2)
self.assertQuerysetEqual(
company_query, [
{
'num_chairs': 2302,
'name': 'Example Inc.',
'num_employees': 2300
},
{
'num_chairs': 5,
'name': 'Foobar Ltd.',
'num_employees': 3
},
{
'num_chairs': 34,
'name': 'Test GmbH',
'num_employees': 32
}
],
lambda o: o,
)
# Law of order of operations is followed
company_query.update(
num_chairs=F('num_employees') + 2 * F('num_employees')
)
self.assertQuerysetEqual(
company_query, [
{
'num_chairs': 6900,
'name': 'Example Inc.',
'num_employees': 2300
},
{
'num_chairs': 9,
'name': 'Foobar Ltd.',
'num_employees': 3
},
{
'num_chairs': 96,
'name': 'Test GmbH',
'num_employees': 32
}
],
lambda o: o,
)
# Law of order of operations can be overridden by parentheses
company_query.update(
num_chairs=((F('num_employees') + 2) * F('num_employees'))
)
self.assertQuerysetEqual(
company_query, [
{
'num_chairs': 5294600,
'name': 'Example Inc.',
'num_employees': 2300
},
{
'num_chairs': 15,
'name': 'Foobar Ltd.',
'num_employees': 3
},
{
'num_chairs': 1088,
'name': 'Test GmbH',
'num_employees': 32
}
],
lambda o: o,
)
# The relation of a foreign key can become copied over to an other
# foreign key.
self.assertEqual(
Company.objects.update(point_of_contact=F('ceo')),
3
)
self.assertQuerysetEqual(
Company.objects.all(), [
"Joe Smith",
"Frank Meyer",
"Max Mustermann",
],
lambda c: six.text_type(c.point_of_contact),
ordered=False
)
c = Company.objects.all()[0]
c.point_of_contact = Employee.objects.create(firstname="Guido", lastname="van Rossum")
c.save()
# F Expressions can also span joins
self.assertQuerysetEqual(
Company.objects.filter(ceo__firstname=F("point_of_contact__firstname")), [
"Foobar Ltd.",
"Test GmbH",
],
lambda c: c.name,
ordered=False
)
Company.objects.exclude(
ceo__firstname=F("point_of_contact__firstname")
).update(name="foo")
self.assertEqual(
Company.objects.exclude(
ceo__firstname=F('point_of_contact__firstname')
).get().name,
"foo",
)
with transaction.atomic():
with self.assertRaises(FieldError):
Company.objects.exclude(
ceo__firstname=F('point_of_contact__firstname')
).update(name=F('point_of_contact__lastname'))
# F expressions can be used to update attributes on single objects
test_gmbh = Company.objects.get(name="Test GmbH")
self.assertEqual(test_gmbh.num_employees, 32)
test_gmbh.num_employees = F("num_employees") + 4
test_gmbh.save()
test_gmbh = Company.objects.get(pk=test_gmbh.pk)
self.assertEqual(test_gmbh.num_employees, 36)
# F expressions cannot be used to update attributes which are foreign
# keys, or attributes which involve joins.
test_gmbh.point_of_contact = None
test_gmbh.save()
self.assertIsNone(test_gmbh.point_of_contact)
def test():
test_gmbh.point_of_contact = F("ceo")
self.assertRaises(ValueError, test)
test_gmbh.point_of_contact = test_gmbh.ceo
test_gmbh.save()
test_gmbh.name = F("ceo__last_name")
self.assertRaises(FieldError, test_gmbh.save)
# F expressions cannot be used to update attributes on objects which do
# not yet exist in the database
acme = Company(
name="The Acme Widget Co.", num_employees=12, num_chairs=5,
ceo=test_gmbh.ceo
)
acme.num_employees = F("num_employees") + 16
self.assertRaises(TypeError, acme.save)
def test_ticket_11722_iexact_lookup(self):
Employee.objects.create(firstname="John", lastname="Doe")
Employee.objects.create(firstname="Test", lastname="test")
queryset = Employee.objects.filter(firstname__iexact=F('lastname'))
self.assertQuerysetEqual(queryset, ["<Employee: Test test>"])
@skipIfDBFeature('has_case_insensitive_like')
def test_ticket_16731_startswith_lookup(self):
Employee.objects.create(firstname="John", lastname="Doe")
e2 = Employee.objects.create(firstname="Jack", lastname="Jackson")
e3 = Employee.objects.create(firstname="Jack", lastname="jackson")
self.assertQuerysetEqual(
Employee.objects.filter(lastname__startswith=F('firstname')),
[e2], lambda x: x)
self.assertQuerysetEqual(
Employee.objects.filter(lastname__istartswith=F('firstname')).order_by('pk'),
[e2, e3], lambda x: x)
def test_ticket_18375_join_reuse(self):
# Test that reverse multijoin F() references and the lookup target
# the same join. Pre #18375 the F() join was generated first, and the
# lookup couldn't reuse that join.
qs = Employee.objects.filter(
company_ceo_set__num_chairs=F('company_ceo_set__num_employees'))
self.assertEqual(str(qs.query).count('JOIN'), 1)
def test_ticket_18375_kwarg_ordering(self):
# The next query was dict-randomization dependent - if the "gte=1"
# was seen first, then the F() will reuse the join generated by the
# gte lookup, if F() was seen first, then it generated a join the
# other lookups could not reuse.
qs = Employee.objects.filter(
company_ceo_set__num_chairs=F('company_ceo_set__num_employees'),
company_ceo_set__num_chairs__gte=1)
self.assertEqual(str(qs.query).count('JOIN'), 1)
def test_ticket_18375_kwarg_ordering_2(self):
# Another similar case for F() than above. Now we have the same join
# in two filter kwargs, one in the lhs lookup, one in F. Here pre
# #18375 the amount of joins generated was random if dict
# randomization was enabled, that is the generated query dependent
# on which clause was seen first.
qs = Employee.objects.filter(
company_ceo_set__num_employees=F('pk'),
pk=F('company_ceo_set__num_employees')
)
self.assertEqual(str(qs.query).count('JOIN'), 1)
def test_ticket_18375_chained_filters(self):
# Test that F() expressions do not reuse joins from previous filter.
qs = Employee.objects.filter(
company_ceo_set__num_employees=F('pk')
).filter(
company_ceo_set__num_employees=F('company_ceo_set__num_employees')
)
self.assertEqual(str(qs.query).count('JOIN'), 2)
def test_F_object_deepcopy(self):
"""
Make sure F objects can be deepcopied (#23492)
"""
f = F("foo")
g = deepcopy(f)
self.assertEqual(f.name, g.name)
class ExpressionsNumericTests(TestCase):
def setUp(self):
Number(integer=-1).save()
Number(integer=42).save()
Number(integer=1337).save()
self.assertEqual(Number.objects.update(float=F('integer')), 3)
def test_fill_with_value_from_same_object(self):
"""
We can fill a value in all objects with an other value of the
same object.
"""
self.assertQuerysetEqual(
Number.objects.all(),
[
'<Number: -1, -1.000>',
'<Number: 42, 42.000>',
'<Number: 1337, 1337.000>'
],
ordered=False
)
def test_increment_value(self):
"""
We can increment a value of all objects in a query set.
"""
self.assertEqual(
Number.objects.filter(integer__gt=0)
.update(integer=F('integer') + 1),
2)
self.assertQuerysetEqual(
Number.objects.all(),
[
'<Number: -1, -1.000>',
'<Number: 43, 42.000>',
'<Number: 1338, 1337.000>'
],
ordered=False
)
def test_filter_not_equals_other_field(self):
"""
We can filter for objects, where a value is not equals the value
of an other field.
"""
self.assertEqual(
Number.objects.filter(integer__gt=0)
.update(integer=F('integer') + 1),
2)
self.assertQuerysetEqual(
Number.objects.exclude(float=F('integer')),
[
'<Number: 43, 42.000>',
'<Number: 1338, 1337.000>'
],
ordered=False
)
def test_complex_expressions(self):
"""
Complex expressions of different connection types are possible.
"""
n = Number.objects.create(integer=10, float=123.45)
self.assertEqual(Number.objects.filter(pk=n.pk)
.update(float=F('integer') + F('float') * 2), 1)
self.assertEqual(Number.objects.get(pk=n.pk).integer, 10)
self.assertEqual(Number.objects.get(pk=n.pk).float, Approximate(256.900, places=3))
class ExpressionOperatorTests(TestCase):
def setUp(self):
self.n = Number.objects.create(integer=42, float=15.5)
def test_lefthand_addition(self):
# LH Addition of floats and integers
Number.objects.filter(pk=self.n.pk).update(
integer=F('integer') + 15,
float=F('float') + 42.7
)
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 57)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(58.200, places=3))
def test_lefthand_subtraction(self):
# LH Subtraction of floats and integers
Number.objects.filter(pk=self.n.pk).update(integer=F('integer') - 15,
float=F('float') - 42.7)
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 27)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(-27.200, places=3))
def test_lefthand_multiplication(self):
# Multiplication of floats and integers
Number.objects.filter(pk=self.n.pk).update(integer=F('integer') * 15,
float=F('float') * 42.7)
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 630)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(661.850, places=3))
def test_lefthand_division(self):
# LH Division of floats and integers
Number.objects.filter(pk=self.n.pk).update(integer=F('integer') / 2,
float=F('float') / 42.7)
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 21)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(0.363, places=3))
def test_lefthand_modulo(self):
# LH Modulo arithmetic on integers
Number.objects.filter(pk=self.n.pk).update(integer=F('integer') % 20)
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 2)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(15.500, places=3))
def test_lefthand_bitwise_and(self):
# LH Bitwise ands on integers
Number.objects.filter(pk=self.n.pk).update(integer=F('integer').bitand(56))
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 40)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(15.500, places=3))
@skipUnlessDBFeature('supports_bitwise_or')
def test_lefthand_bitwise_or(self):
# LH Bitwise or on integers
Number.objects.filter(pk=self.n.pk).update(integer=F('integer').bitor(48))
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'),
float=42.7 + F('float'))
# RH Addition of floats and integers
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 57)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(58.200, places=3))
def test_right_hand_subtraction(self):
Number.objects.filter(pk=self.n.pk).update(integer=15 - F('integer'),
float=42.7 - F('float'))
# RH Subtraction of floats and integers
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, -27)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(27.200, places=3))
def test_right_hand_multiplication(self):
# RH Multiplication of floats and integers
Number.objects.filter(pk=self.n.pk).update(integer=15 * F('integer'),
float=42.7 * F('float'))
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 630)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(661.850, places=3))
def test_right_hand_division(self):
# RH Division of floats and integers
Number.objects.filter(pk=self.n.pk).update(integer=640 / F('integer'),
float=42.7 / F('float'))
self.assertEqual(Number.objects.get(pk=self.n.pk).integer, 15)
self.assertEqual(Number.objects.get(pk=self.n.pk).float, Approximate(2.755, places=3))
def test_right_hand_modulo(self):
# RH Modulo arithmetic on integers
Number.objects.filter(pk=self.n.pk).update(integer=69 % F('integer'))
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):
def setUp(self):
sday = datetime.date(2010, 6, 25)
stime = datetime.datetime(2010, 6, 25, 12, 15, 30, 747000)
midnight = datetime.time(0)
delta0 = datetime.timedelta(0)
delta1 = datetime.timedelta(microseconds=253000)
delta2 = datetime.timedelta(seconds=44)
delta3 = datetime.timedelta(hours=21, minutes=8)
delta4 = datetime.timedelta(days=10)
# Test data is set so that deltas and delays will be
# strictly increasing.
self.deltas = []
self.delays = []
self.days_long = []
# e0: started same day as assigned, zero duration
end = stime + delta0
e0 = Experiment.objects.create(name='e0', assigned=sday, start=stime,
end=end, completed=end.date())
self.deltas.append(delta0)
self.delays.append(e0.start -
datetime.datetime.combine(e0.assigned, midnight))
self.days_long.append(e0.completed - e0.assigned)
# e1: started one day after assigned, tiny duration, data
# set so that end time has no fractional seconds, which
# tests an edge case on sqlite. This Experiment is only
# included in the test data when the DB supports microsecond
# precision.
if connection.features.supports_microsecond_precision:
delay = datetime.timedelta(1)
end = stime + delay + delta1
e1 = Experiment.objects.create(name='e1', assigned=sday,
start=stime + delay, end=end, completed=end.date())
self.deltas.append(delta1)
self.delays.append(e1.start -
datetime.datetime.combine(e1.assigned, midnight))
self.days_long.append(e1.completed - e1.assigned)
# e2: started three days after assigned, small duration
end = stime + delta2
e2 = Experiment.objects.create(name='e2',
assigned=sday - datetime.timedelta(3), start=stime, end=end,
completed=end.date())
self.deltas.append(delta2)
self.delays.append(e2.start -
datetime.datetime.combine(e2.assigned, midnight))
self.days_long.append(e2.completed - e2.assigned)
# e3: started four days after assigned, medium duration
delay = datetime.timedelta(4)
end = stime + delay + delta3
e3 = Experiment.objects.create(name='e3',
assigned=sday, start=stime + delay, end=end, completed=end.date())
self.deltas.append(delta3)
self.delays.append(e3.start -
datetime.datetime.combine(e3.assigned, midnight))
self.days_long.append(e3.completed - e3.assigned)
# e4: started 10 days after assignment, long duration
end = stime + delta4
e4 = Experiment.objects.create(name='e4',
assigned=sday - datetime.timedelta(10), start=stime, end=end,
completed=end.date())
self.deltas.append(delta4)
self.delays.append(e4.start -
datetime.datetime.combine(e4.assigned, midnight))
self.days_long.append(e4.completed - e4.assigned)
self.expnames = [e.name for e in Experiment.objects.all()]
def test_multiple_query_compilation(self):
# Ticket #21643
queryset = Experiment.objects.filter(end__lt=F('start') + datetime.timedelta(hours=1))
q1 = str(queryset.query)
q2 = str(queryset.query)
self.assertEqual(q1, q2)
def test_query_clone(self):
# Ticket #21643
qs = Experiment.objects.filter(end__lt=F('start') + datetime.timedelta(hours=1))
qs2 = qs.all()
list(qs)
list(qs2)
def test_delta_add(self):
for i in range(len(self.deltas)):
delta = self.deltas[i]
test_set = [e.name for e in
Experiment.objects.filter(end__lt=F('start') + delta)]
self.assertEqual(test_set, self.expnames[:i])
test_set = [e.name for e in
Experiment.objects.filter(end__lte=F('start') + delta)]
self.assertEqual(test_set, self.expnames[:i + 1])
def test_delta_subtract(self):
for i in range(len(self.deltas)):
delta = self.deltas[i]
test_set = [e.name for e in
Experiment.objects.filter(start__gt=F('end') - delta)]
self.assertEqual(test_set, self.expnames[:i])
test_set = [e.name for e in
Experiment.objects.filter(start__gte=F('end') - delta)]
self.assertEqual(test_set, self.expnames[:i + 1])
def test_exclude(self):
for i in range(len(self.deltas)):
delta = self.deltas[i]
test_set = [e.name for e in
Experiment.objects.exclude(end__lt=F('start') + delta)]
self.assertEqual(test_set, self.expnames[i:])
test_set = [e.name for e in
Experiment.objects.exclude(end__lte=F('start') + delta)]
self.assertEqual(test_set, self.expnames[i + 1:])
def test_date_comparison(self):
for i in range(len(self.days_long)):
days = self.days_long[i]
test_set = [e.name for e in
Experiment.objects.filter(completed__lt=F('assigned') + days)]
self.assertEqual(test_set, self.expnames[:i])
test_set = [e.name for e in
Experiment.objects.filter(completed__lte=F('assigned') + days)]
self.assertEqual(test_set, self.expnames[:i + 1])
@skipUnlessDBFeature("supports_mixed_date_datetime_comparisons")
def test_mixed_comparisons1(self):
for i in range(len(self.delays)):
delay = self.delays[i]
if not connection.features.supports_microsecond_precision:
delay = datetime.timedelta(delay.days, delay.seconds)
test_set = [e.name for e in
Experiment.objects.filter(assigned__gt=F('start') - delay)]
self.assertEqual(test_set, self.expnames[:i])
test_set = [e.name for e in
Experiment.objects.filter(assigned__gte=F('start') - delay)]
self.assertEqual(test_set, self.expnames[:i + 1])
def test_mixed_comparisons2(self):
delays = [datetime.timedelta(delay.days) for delay in self.delays]
for i in range(len(delays)):
delay = delays[i]
test_set = [e.name for e in
Experiment.objects.filter(start__lt=F('assigned') + delay)]
self.assertEqual(test_set, self.expnames[:i])
test_set = [e.name for e in
Experiment.objects.filter(start__lte=F('assigned') + delay +
datetime.timedelta(1))]
self.assertEqual(test_set, self.expnames[:i + 1])
def test_delta_update(self):
for i in range(len(self.deltas)):
delta = self.deltas[i]
exps = Experiment.objects.all()
expected_durations = [e.duration() for e in exps]
expected_starts = [e.start + delta for e in exps]
expected_ends = [e.end + delta for e in exps]
Experiment.objects.update(start=F('start') + delta, end=F('end') + delta)
exps = Experiment.objects.all()
new_starts = [e.start for e in exps]
new_ends = [e.end for e in exps]
new_durations = [e.duration() for e in exps]
self.assertEqual(expected_starts, new_starts)
self.assertEqual(expected_ends, new_ends)
self.assertEqual(expected_durations, new_durations)
def test_delta_invalid_op_mult(self):
raised = False
try:
repr(Experiment.objects.filter(end__lt=F('start') * self.deltas[0]))
except TypeError:
raised = True
self.assertTrue(raised, "TypeError not raised on attempt to multiply datetime by timedelta.")
def test_delta_invalid_op_div(self):
raised = False
try:
repr(Experiment.objects.filter(end__lt=F('start') / self.deltas[0]))
except TypeError:
raised = True
self.assertTrue(raised, "TypeError not raised on attempt to divide datetime by timedelta.")
def test_delta_invalid_op_mod(self):
raised = False
try:
repr(Experiment.objects.filter(end__lt=F('start') % self.deltas[0]))
except TypeError:
raised = True
self.assertTrue(raised, "TypeError not raised on attempt to modulo divide datetime by timedelta.")
def test_delta_invalid_op_and(self):
raised = False
try:
repr(Experiment.objects.filter(end__lt=F('start').bitand(self.deltas[0])))
except TypeError:
raised = True
self.assertTrue(raised, "TypeError not raised on attempt to binary and a datetime with a timedelta.")
def test_delta_invalid_op_or(self):
raised = False
try:
repr(Experiment.objects.filter(end__lt=F('start').bitor(self.deltas[0])))
except TypeError:
raised = True
self.assertTrue(raised, "TypeError not raised on attempt to binary or a datetime with a timedelta.")