import datetime from copy import deepcopy from django.core.exceptions import FieldError, MultipleObjectsReturned from django.db import models, transaction from django.test import TestCase from django.utils import six from django.utils.translation import ugettext_lazy from .models import ( Article, Category, Child, First, Parent, Record, Relation, Reporter, School, Student, Third, ToFieldChild, ) class ManyToOneTests(TestCase): def setUp(self): # Create a few Reporters. self.r = Reporter(first_name='John', last_name='Smith', email='john@example.com') self.r.save() self.r2 = Reporter(first_name='Paul', last_name='Jones', email='paul@example.com') self.r2.save() # Create an Article. self.a = Article(id=None, headline="This is a test", pub_date=datetime.date(2005, 7, 27), reporter=self.r) self.a.save() def test_get(self): # Article objects have access to their related Reporter objects. r = self.a.reporter self.assertEqual(r.id, self.r.id) # These are strings instead of unicode strings because that's what was used in # the creation of this reporter (and we haven't refreshed the data from the # database, which always returns unicode strings). self.assertEqual((r.first_name, self.r.last_name), ('John', 'Smith')) def test_create(self): # You can also instantiate an Article by passing the Reporter's ID # instead of a Reporter object. a3 = Article(id=None, headline="Third article", pub_date=datetime.date(2005, 7, 27), reporter_id=self.r.id) a3.save() self.assertEqual(a3.reporter.id, self.r.id) # Similarly, the reporter ID can be a string. a4 = Article(id=None, headline="Fourth article", pub_date=datetime.date(2005, 7, 27), reporter_id=str(self.r.id)) a4.save() self.assertEqual(repr(a4.reporter), "") def test_add(self): # Create an Article via the Reporter object. new_article = self.r.article_set.create(headline="John's second story", pub_date=datetime.date(2005, 7, 29)) self.assertEqual(repr(new_article), "") self.assertEqual(new_article.reporter.id, self.r.id) # Create a new article, and add it to the article set. new_article2 = Article(headline="Paul's story", pub_date=datetime.date(2006, 1, 17)) self.r.article_set.add(new_article2) self.assertEqual(new_article2.reporter.id, self.r.id) self.assertQuerysetEqual(self.r.article_set.all(), [ "", "", "", ]) # Add the same article to a different article set - check that it moves. self.r2.article_set.add(new_article2) self.assertEqual(new_article2.reporter.id, self.r2.id) self.assertQuerysetEqual(self.r2.article_set.all(), [""]) # Adding an object of the wrong type raises TypeError. with transaction.atomic(): with six.assertRaisesRegex(self, TypeError, "'Article' instance expected, got ", "", ]) def test_set(self): new_article = self.r.article_set.create(headline="John's second story", pub_date=datetime.date(2005, 7, 29)) new_article2 = self.r2.article_set.create(headline="Paul's story", pub_date=datetime.date(2006, 1, 17)) # Assign the article to the reporter. new_article2.reporter = self.r new_article2.save() self.assertEqual(repr(new_article2.reporter), "") self.assertEqual(new_article2.reporter.id, self.r.id) self.assertQuerysetEqual(self.r.article_set.all(), [ "", "", "", ]) self.assertQuerysetEqual(self.r2.article_set.all(), []) # Set the article back again. self.r2.article_set.set([new_article, new_article2]) self.assertQuerysetEqual(self.r.article_set.all(), [""]) self.assertQuerysetEqual(self.r2.article_set.all(), [ "", "", ]) # Funny case - because the ForeignKey cannot be null, # existing members of the set must remain. self.r.article_set.set([new_article]) self.assertQuerysetEqual(self.r.article_set.all(), [ "", "", ]) self.assertQuerysetEqual(self.r2.article_set.all(), [""]) def test_assign(self): new_article = self.r.article_set.create(headline="John's second story", pub_date=datetime.date(2005, 7, 29)) new_article2 = self.r2.article_set.create(headline="Paul's story", pub_date=datetime.date(2006, 1, 17)) # Assign the article to the reporter directly using the descriptor. new_article2.reporter = self.r new_article2.save() self.assertEqual(repr(new_article2.reporter), "") self.assertEqual(new_article2.reporter.id, self.r.id) self.assertQuerysetEqual(self.r.article_set.all(), [ "", "", "", ]) self.assertQuerysetEqual(self.r2.article_set.all(), []) # Set the article back again using set descriptor. self.r2.article_set = [new_article, new_article2] self.assertQuerysetEqual(self.r.article_set.all(), [""]) self.assertQuerysetEqual(self.r2.article_set.all(), [ "", "", ]) # Funny case - assignment notation can only go so far; because the # ForeignKey cannot be null, existing members of the set must remain. self.r.article_set = [new_article] self.assertQuerysetEqual(self.r.article_set.all(), [ "", "", ]) self.assertQuerysetEqual(self.r2.article_set.all(), [""]) # Reporter cannot be null - there should not be a clear or remove method self.assertFalse(hasattr(self.r2.article_set, 'remove')) self.assertFalse(hasattr(self.r2.article_set, 'clear')) def test_selects(self): self.r.article_set.create(headline="John's second story", pub_date=datetime.date(2005, 7, 29)) self.r2.article_set.create(headline="Paul's story", pub_date=datetime.date(2006, 1, 17)) # Reporter objects have access to their related Article objects. self.assertQuerysetEqual(self.r.article_set.all(), [ "", "", ]) self.assertQuerysetEqual(self.r.article_set.filter(headline__startswith='This'), [""]) self.assertEqual(self.r.article_set.count(), 2) self.assertEqual(self.r2.article_set.count(), 1) # Get articles by id self.assertQuerysetEqual(Article.objects.filter(id__exact=self.a.id), [""]) self.assertQuerysetEqual(Article.objects.filter(pk=self.a.id), [""]) # Query on an article property self.assertQuerysetEqual(Article.objects.filter(headline__startswith='This'), [""]) # The API automatically follows relationships as far as you need. # Use double underscores to separate relationships. # This works as many levels deep as you want. There's no limit. # Find all Articles for any Reporter whose first name is "John". self.assertQuerysetEqual(Article.objects.filter(reporter__first_name__exact='John'), [ "", "", ]) # Check that implied __exact also works self.assertQuerysetEqual(Article.objects.filter(reporter__first_name='John'), [ "", "", ]) # Query twice over the related field. self.assertQuerysetEqual( Article.objects.filter(reporter__first_name__exact='John', reporter__last_name__exact='Smith'), [ "", "", ]) # The underlying query only makes one join when a related table is referenced twice. queryset = Article.objects.filter(reporter__first_name__exact='John', reporter__last_name__exact='Smith') self.assertNumQueries(1, list, queryset) self.assertEqual(queryset.query.get_compiler(queryset.db).as_sql()[0].count('INNER JOIN'), 1) # The automatically joined table has a predictable name. self.assertQuerysetEqual( Article.objects.filter(reporter__first_name__exact='John').extra( where=["many_to_one_reporter.last_name='Smith'"]), [ "", "", ]) # ... and should work fine with the unicode that comes out of forms.Form.cleaned_data self.assertQuerysetEqual( (Article.objects .filter(reporter__first_name__exact='John') .extra(where=["many_to_one_reporter.last_name='%s'" % 'Smith'])), [ "", "", ]) # Find all Articles for a Reporter. # Use direct ID check, pk check, and object comparison self.assertQuerysetEqual( Article.objects.filter(reporter__id__exact=self.r.id), [ "", "", ]) self.assertQuerysetEqual( Article.objects.filter(reporter__pk=self.r.id), [ "", "", ]) self.assertQuerysetEqual( Article.objects.filter(reporter=self.r.id), [ "", "", ]) self.assertQuerysetEqual( Article.objects.filter(reporter=self.r), [ "", "", ]) self.assertQuerysetEqual( Article.objects.filter(reporter__in=[self.r.id, self.r2.id]).distinct(), [ "", "", "", ]) self.assertQuerysetEqual( Article.objects.filter(reporter__in=[self.r, self.r2]).distinct(), [ "", "", "", ]) # You can also use a queryset instead of a literal list of instances. # The queryset must be reduced to a list of values using values(), # then converted into a query self.assertQuerysetEqual( Article.objects.filter( reporter__in=Reporter.objects.filter(first_name='John').values('pk').query ).distinct(), [ "", "", ]) def test_reverse_selects(self): a3 = Article.objects.create(id=None, headline="Third article", pub_date=datetime.date(2005, 7, 27), reporter_id=self.r.id) Article.objects.create(id=None, headline="Fourth article", pub_date=datetime.date(2005, 7, 27), reporter_id=str(self.r.id)) # Reporters can be queried self.assertQuerysetEqual(Reporter.objects.filter(id__exact=self.r.id), [""]) self.assertQuerysetEqual(Reporter.objects.filter(pk=self.r.id), [""]) self.assertQuerysetEqual(Reporter.objects.filter(first_name__startswith='John'), [""]) # Reporters can query in opposite direction of ForeignKey definition self.assertQuerysetEqual(Reporter.objects.filter(article__id__exact=self.a.id), [""]) self.assertQuerysetEqual(Reporter.objects.filter(article__pk=self.a.id), [""]) self.assertQuerysetEqual(Reporter.objects.filter(article=self.a.id), [""]) self.assertQuerysetEqual(Reporter.objects.filter(article=self.a), [""]) self.assertQuerysetEqual( Reporter.objects.filter(article__in=[self.a.id, a3.id]).distinct(), [""]) self.assertQuerysetEqual( Reporter.objects.filter(article__in=[self.a.id, a3]).distinct(), [""]) self.assertQuerysetEqual( Reporter.objects.filter(article__in=[self.a, a3]).distinct(), [""]) self.assertQuerysetEqual( Reporter.objects.filter(article__headline__startswith='T'), ["", ""], ordered=False ) self.assertQuerysetEqual( Reporter.objects.filter(article__headline__startswith='T').distinct(), [""]) # Counting in the opposite direction works in conjunction with distinct() self.assertEqual( Reporter.objects.filter(article__headline__startswith='T').count(), 2) self.assertEqual( Reporter.objects.filter(article__headline__startswith='T').distinct().count(), 1) # Queries can go round in circles. self.assertQuerysetEqual( Reporter.objects.filter(article__reporter__first_name__startswith='John'), [ "", "", "", ], ordered=False ) self.assertQuerysetEqual( Reporter.objects.filter(article__reporter__first_name__startswith='John').distinct(), [""]) self.assertQuerysetEqual( Reporter.objects.filter(article__reporter__exact=self.r).distinct(), [""]) # Check that implied __exact also works. self.assertQuerysetEqual( Reporter.objects.filter(article__reporter=self.r).distinct(), [""]) # It's possible to use values() calls across many-to-one relations. # (Note, too, that we clear the ordering here so as not to drag the # 'headline' field into the columns being used to determine uniqueness) d = {'reporter__first_name': 'John', 'reporter__last_name': 'Smith'} self.assertEqual([d], list(Article.objects.filter(reporter=self.r).distinct().order_by() .values('reporter__first_name', 'reporter__last_name'))) def test_select_related(self): # Check that Article.objects.select_related().dates() works properly when # there are multiple Articles with the same date but different foreign-key # objects (Reporters). r1 = Reporter.objects.create(first_name='Mike', last_name='Royko', email='royko@suntimes.com') r2 = Reporter.objects.create(first_name='John', last_name='Kass', email='jkass@tribune.com') Article.objects.create(headline='First', pub_date=datetime.date(1980, 4, 23), reporter=r1) Article.objects.create(headline='Second', pub_date=datetime.date(1980, 4, 23), reporter=r2) self.assertEqual(list(Article.objects.select_related().dates('pub_date', 'day')), [ datetime.date(1980, 4, 23), datetime.date(2005, 7, 27), ]) self.assertEqual(list(Article.objects.select_related().dates('pub_date', 'month')), [ datetime.date(1980, 4, 1), datetime.date(2005, 7, 1), ]) self.assertEqual(list(Article.objects.select_related().dates('pub_date', 'year')), [ datetime.date(1980, 1, 1), datetime.date(2005, 1, 1), ]) def test_delete(self): self.r.article_set.create(headline="John's second story", pub_date=datetime.date(2005, 7, 29)) self.r2.article_set.create(headline="Paul's story", pub_date=datetime.date(2006, 1, 17)) Article.objects.create(id=None, headline="Third article", pub_date=datetime.date(2005, 7, 27), reporter_id=self.r.id) Article.objects.create(id=None, headline="Fourth article", pub_date=datetime.date(2005, 7, 27), reporter_id=str(self.r.id)) # If you delete a reporter, his articles will be deleted. self.assertQuerysetEqual(Article.objects.all(), [ "", "", "", "", "", ]) self.assertQuerysetEqual(Reporter.objects.order_by('first_name'), [ "", "", ]) self.r2.delete() self.assertQuerysetEqual(Article.objects.all(), [ "", "", "", "", ]) self.assertQuerysetEqual(Reporter.objects.order_by('first_name'), [""]) # You can delete using a JOIN in the query. Reporter.objects.filter(article__headline__startswith='This').delete() self.assertQuerysetEqual(Reporter.objects.all(), []) self.assertQuerysetEqual(Article.objects.all(), []) def test_explicit_fk(self): # Create a new Article with get_or_create using an explicit value # for a ForeignKey. a2, created = Article.objects.get_or_create(id=None, headline="John's second test", pub_date=datetime.date(2011, 5, 7), reporter_id=self.r.id) self.assertTrue(created) self.assertEqual(a2.reporter.id, self.r.id) # You can specify filters containing the explicit FK value. self.assertQuerysetEqual( Article.objects.filter(reporter_id__exact=self.r.id), [ "", "", ]) # Create an Article by Paul for the same date. a3 = Article.objects.create(id=None, headline="Paul's commentary", pub_date=datetime.date(2011, 5, 7), reporter_id=self.r2.id) self.assertEqual(a3.reporter.id, self.r2.id) # Get should respect explicit foreign keys as well. self.assertRaises(MultipleObjectsReturned, Article.objects.get, reporter_id=self.r.id) self.assertEqual(repr(a3), repr(Article.objects.get(reporter_id=self.r2.id, pub_date=datetime.date(2011, 5, 7)))) def test_deepcopy_and_circular_references(self): # Regression for #12876 -- Model methods that include queries that # recursive don't cause recursion depth problems under deepcopy. self.r.cached_query = Article.objects.filter(reporter=self.r) self.assertEqual(repr(deepcopy(self.r)), "") def test_manager_class_caching(self): r1 = Reporter.objects.create(first_name='Mike') r2 = Reporter.objects.create(first_name='John') # Same twice self.assertIs(r1.article_set.__class__, r1.article_set.__class__) # Same as each other self.assertIs(r1.article_set.__class__, r2.article_set.__class__) def test_create_relation_with_ugettext_lazy(self): reporter = Reporter.objects.create(first_name='John', last_name='Smith', email='john.smith@example.com') lazy = ugettext_lazy('test') reporter.article_set.create(headline=lazy, pub_date=datetime.date(2011, 6, 10)) notlazy = six.text_type(lazy) article = reporter.article_set.get() self.assertEqual(article.headline, notlazy) def test_values_list_exception(self): expected_message = "Cannot resolve keyword 'notafield' into field. Choices are: %s" self.assertRaisesMessage(FieldError, expected_message % ', '.join(sorted(f.name for f in Reporter._meta.get_fields())), Article.objects.values_list, 'reporter__notafield') self.assertRaisesMessage(FieldError, expected_message % ', '.join(['EXTRA'] + sorted(f.name for f in Article._meta.get_fields())), Article.objects.extra(select={'EXTRA': 'EXTRA_SELECT'}).values_list, 'notafield') def test_fk_assignment_and_related_object_cache(self): # Tests of ForeignKey assignment and the related-object cache (see #6886). p = Parent.objects.create(name="Parent") c = Child.objects.create(name="Child", parent=p) # Look up the object again so that we get a "fresh" object. c = Child.objects.get(name="Child") p = c.parent # Accessing the related object again returns the exactly same object. self.assertIs(c.parent, p) # But if we kill the cache, we get a new object. del c._parent_cache self.assertIsNot(c.parent, p) # Assigning a new object results in that object getting cached immediately. p2 = Parent.objects.create(name="Parent 2") c.parent = p2 self.assertIs(c.parent, p2) # Assigning None succeeds if field is null=True. p.bestchild = None self.assertIsNone(p.bestchild) # bestchild should still be None after saving. p.save() self.assertIsNone(p.bestchild) # bestchild should still be None after fetching the object again. p = Parent.objects.get(name="Parent") self.assertIsNone(p.bestchild) # Assigning None fails: Child.parent is null=False. self.assertRaises(ValueError, setattr, c, "parent", None) # You also can't assign an object of the wrong type here self.assertRaises(ValueError, setattr, c, "parent", First(id=1, second=1)) # Nor can you explicitly assign None to Child.parent during object # creation (regression for #9649). self.assertRaises(ValueError, Child, name='xyzzy', parent=None) self.assertRaises(ValueError, Child.objects.create, name='xyzzy', parent=None) # Creation using keyword argument should cache the related object. p = Parent.objects.get(name="Parent") c = Child(parent=p) self.assertIs(c.parent, p) # Creation using keyword argument and unsaved related instance (#8070). p = Parent() with self.assertRaisesMessage(ValueError, 'Cannot assign "%r": "%s" instance isn\'t saved in the database.' % (p, Child.parent.field.rel.to._meta.object_name)): Child(parent=p) with self.assertRaisesMessage(ValueError, 'Cannot assign "%r": "%s" instance isn\'t saved in the database.' % (p, Child.parent.field.rel.to._meta.object_name)): ToFieldChild(parent=p) # Creation using attname keyword argument and an id will cause the # related object to be fetched. p = Parent.objects.get(name="Parent") c = Child(parent_id=p.id) self.assertIsNot(c.parent, p) self.assertEqual(c.parent, p) def test_multiple_foreignkeys(self): # Test of multiple ForeignKeys to the same model (bug #7125). c1 = Category.objects.create(name='First') c2 = Category.objects.create(name='Second') c3 = Category.objects.create(name='Third') r1 = Record.objects.create(category=c1) r2 = Record.objects.create(category=c1) r3 = Record.objects.create(category=c2) r4 = Record.objects.create(category=c2) r5 = Record.objects.create(category=c3) Relation.objects.create(left=r1, right=r2) Relation.objects.create(left=r3, right=r4) Relation.objects.create(left=r1, right=r3) Relation.objects.create(left=r5, right=r2) Relation.objects.create(left=r3, right=r2) q1 = Relation.objects.filter(left__category__name__in=['First'], right__category__name__in=['Second']) self.assertQuerysetEqual(q1, [""]) q2 = Category.objects.filter(record__left_set__right__category__name='Second').order_by('name') self.assertQuerysetEqual(q2, ["", ""]) p = Parent.objects.create(name="Parent") c = Child.objects.create(name="Child", parent=p) self.assertRaises(ValueError, Child.objects.create, name="Grandchild", parent=c) def test_fk_instantiation_outside_model(self): # Regression for #12190 -- Should be able to instantiate a FK outside # of a model, and interrogate its related field. cat = models.ForeignKey(Category) self.assertEqual('id', cat.rel.get_related_field().name) def test_relation_unsaved(self): # Test that the _set manager does not join on Null value fields (#17541) Third.objects.create(name='Third 1') Third.objects.create(name='Third 2') th = Third(name="testing") # The object isn't saved an thus the relation field is null - we won't even # execute a query in this case. with self.assertNumQueries(0): self.assertEqual(th.child_set.count(), 0) th.save() # Now the model is saved, so we will need to execute an query. with self.assertNumQueries(1): self.assertEqual(th.child_set.count(), 0) def test_related_object(self): public_school = School.objects.create(is_public=True) public_student = Student.objects.create(school=public_school) private_school = School.objects.create(is_public=False) private_student = Student.objects.create(school=private_school) # Only one school is available via all() due to the custom default manager. self.assertQuerysetEqual( School.objects.all(), [""] ) self.assertEqual(public_student.school, public_school) # Make sure the base manager is used so that an student can still access # its related school even if the default manager doesn't normally # allow it. self.assertEqual(private_student.school, private_school) # If the manager is marked "use_for_related_fields", it'll get used instead # of the "bare" queryset. Usually you'd define this as a property on the class, # but this approximates that in a way that's easier in tests. School.objects.use_for_related_fields = True try: private_student = Student.objects.get(pk=private_student.pk) self.assertRaises(School.DoesNotExist, lambda: private_student.school) finally: School.objects.use_for_related_fields = False def test_hasattr_related_object(self): # The exception raised on attribute access when a related object # doesn't exist should be an instance of a subclass of `AttributeError` # refs #21563 self.assertFalse(hasattr(Article(), 'reporter'))