Testing applications Django with py.test (Django Stockholm meetup)

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.VMUJQMFUFTUpMFT # Typical contents of app/tests/__init__.py: from .test_foo import *
from .test_bar import * from .test_spam import *

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QZUFTUUFTUTUZMF def greeter(name): return 'Hello %s!' %
name def test_greeter(): assert greeter('Andreas') == 'Hello Andreas'

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)PXUPSVOUFTUT # run all tests $ py.test # run a
specific file $ py.test tests/app/test_views.py # run test which matches tests named *test_foo* $ py.test tests/app/test_views.py -‐k test_foo # run all non database tests (more on this later) $ py.test tests/app -‐m 'not django_db'

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%BUBCBTFVTBHF w 8JUIQZUFTUEKBOHP ZPVNVTUCFFYQMJDJUBCPVU EBUBCBTFBDDFTT w %BUBCBTFBDDFTTJTSFRVFTUFEXJUIUIF pytest.mark.django_dbNBSLFS

%BUBCBTFVTBHF import pytest def test_without_db_access(): # any
db accesses will raise an error pass @pytest.mark.django_db def test_with_db_access(): # test db is available pass

%BUBCBTFVTBHF import pytest # Allow all tests in this module
database access pytestmark = pytest.mark.django_db def test_with_db_access_1(): pass def test_with_db_access_2(): pass def test_with_db_access_3(): pass

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%KBOHPUFTUpYUVSFT [ { "model": "myapp.person", "pk": 1, "fields": { "first_name":
"John", "last_name": "Lennon" } }, { "model": "myapp.person", "pk": 2, "fields": { "first_name": "Paul", "last_name": "McCartney" } } ]

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GBDUPSZ@CPZFYBNQMF # models.py from django.db import models class Group(models.Model):
name = models.TextField() class Person(models.Model): first_name = models.TextField() last_name = models.TextField() group = models.ForeignKey(Group) def group_letter(self): return self.group.name[0].upper() def full_name(self): return '%s %s' % (self.first_name, self.last_name) # factories.py import factory from app.models import Person, Group class GroupFactory(factory.Factory): FACTORY_FOR = Group name = 'Developers' class PersonFactory(factory.Factory): FACTORY_FOR = Person first_name = 'John' last_name = 'Doe' group = factory.SubFactory(GroupFactory)

GBDUPSZ@CPZFYBNQMF from factories import PersonFactory def test_full_name():
person = PersonFactory.build(first_name='Andreas', last_name='Pelme') assert person.full_name() == 'Andreas Pelme' def test_group_letter(): person = PersonFactory.build(group__name='admins') assert person.group_letter() == 'A'

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QZUFTUpYUVSFT import pytest from my_module import MyClass @pytest.fixture def my_object():
return MyClass() def test_foo(my_object): assert my_object.foo() == 'foo' def test_bar(my_object): assert my_object.bar() == 'bar'

QZUFTUEKBOHPpYUVSFT def test_changing_settings(settings): settings.DATE_FORMAT = 'Y-‐m-‐d'
# call code that uses settings.DATE_FORMAT ... # the settings will be automatically reset after this test def test_with_testclient(client): # client is an instance of Django's TestClient, just like # self.client in a Django TestCase response = client.get('/foo/bar') assert response.status_code == 200

'BDUPSZ pYUVSFT import pytest from factories import PersonFactory @pytest.fixture def
person(): return PersonFactory.build() def test_with_person(person): # Test something on the Person object pass

'BDUPSZ pYUVSFT import pytest from factories import UserFactory @pytest.fixture def
user_in_db(db): # The db argument makes database access allowed return UserFactory.create() @pytest.mark.django_db def test_with_saved_user(user_in_db): # user_in_db is a saved user pass

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Testing applications Django with py.test (Django Stockholm meetup)

Testing applications Django with py.test (Django Stockholm meetup)

Andreas Pelme

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.VMUJQMFUFTUpMFT # Typical contents of app/tests/init.py: from .test_foo import *

QZUFTU w (FOFSBMQVSQPTF1ZUIPOUFTUJOHUPPM w 6TFECZ1Z1Z .P[JMMB TJY 4FOUSZ w

QZUFTUUFTUTUZMF def greeter(name): return 'Hello %s!' %

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QZUFTUEKBOHPTFUVQ w pip install pytest-‐django w 3FRVJSFTZPVSDPEFUPCFPO1ZUIPOQBUI w add2virtualenv

8IFSFUPQVUUFTUT w #ZEFGBVMUBOZpMFUIBUNBUDIFTtest_.py w 5FTUEJTDPWFSZJTDPOpHVSBCMF w 4FUpython_files = .pyJOQZUFTUJOJ w

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)PXUPSVOUFTUT # run all tests $ py.test # run a

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%BUBCBTFVTBHF w 8JUIQZUFTUEKBOHP ZPVNVTUCFFYQMJDJUBCPVU EBUBCBTFBDDFTT w %BUBCBTFBDDFTTJTSFRVFTUFEXJUIUIF pytest.mark.django_dbNBSLFS

%BUBCBTFVTBHF import pytest def test_without_db_access(): # any

%BUBCBTFVTBHF import pytest # Allow all tests in this module

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%KBOHPUFTUpYUVSFT [ { "model": "myapp.person", "pk": 1, "fields": { "first_name":

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GBDUPSZ@CPZFYBNQMF # models.py from django.db import models class Group(models.Model):

GBDUPSZ@CPZFYBNQMF from factories import PersonFactory def test_full_name():

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QZUFTUpYUVSFT import pytest from my_module import MyClass @pytest.fixture def my_object():

QZUFTUEKBOHPpYUVSFT def test_changing_settings(settings): settings.DATE_FORMAT = 'Y-‐m-‐d'

'BDUPSZ pYUVSFT import pytest from factories import PersonFactory @pytest.fixture def

'BDUPSZ pYUVSFT import pytest from factories import UserFactory @pytest.fixture def

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