/tests/modeltests/transactions/tests_25.py

  1from __future__ import with_statement
  2
  3from django.db import connection, transaction, IntegrityError
  4from django.test import TransactionTestCase, skipUnlessDBFeature
  5
  6from models import Reporter
  7
  8
  9class TransactionContextManagerTests(TransactionTestCase):
 10    def create_reporter_and_fail(self):
 11        Reporter.objects.create(first_name="Bob", last_name="Holtzman")
 12        raise Exception
 13
 14    @skipUnlessDBFeature('supports_transactions')
 15    def test_autocommit(self):
 16        """
 17        The default behavior is to autocommit after each save() action.
 18        """
 19        with self.assertRaises(Exception):
 20            self.create_reporter_and_fail()
 21        # The object created before the exception still exists
 22        self.assertEqual(Reporter.objects.count(), 1)
 23
 24    @skipUnlessDBFeature('supports_transactions')
 25    def test_autocommit_context_manager(self):
 26        """
 27        The autocommit context manager works exactly the same as the default
 28        behavior.
 29        """
 30        with self.assertRaises(Exception):
 31            with transaction.autocommit():
 32                self.create_reporter_and_fail()
 33
 34        self.assertEqual(Reporter.objects.count(), 1)
 35
 36    @skipUnlessDBFeature('supports_transactions')
 37    def test_autocommit_context_manager_with_using(self):
 38        """
 39        The autocommit context manager also works with a using argument.
 40        """
 41        with self.assertRaises(Exception):
 42            with transaction.autocommit(using="default"):
 43                self.create_reporter_and_fail()
 44
 45        self.assertEqual(Reporter.objects.count(), 1)
 46
 47    @skipUnlessDBFeature('supports_transactions')
 48    def test_commit_on_success(self):
 49        """
 50        With the commit_on_success context manager, the transaction is only
 51        committed if the block doesn't throw an exception.
 52        """
 53        with self.assertRaises(Exception):
 54            with transaction.commit_on_success():
 55                self.create_reporter_and_fail()
 56
 57        self.assertEqual(Reporter.objects.count(), 0)
 58
 59    @skipUnlessDBFeature('supports_transactions')
 60    def test_commit_on_success_with_using(self):
 61        """
 62        The commit_on_success context manager also works with a using argument.
 63        """
 64        with self.assertRaises(Exception):
 65            with transaction.commit_on_success(using="default"):
 66                self.create_reporter_and_fail()
 67
 68        self.assertEqual(Reporter.objects.count(), 0)
 69
 70    @skipUnlessDBFeature('supports_transactions')
 71    def test_commit_on_success_succeed(self):
 72        """
 73        If there aren't any exceptions, the data will get saved.
 74        """
 75        Reporter.objects.create(first_name="Alice", last_name="Smith")
 76        with transaction.commit_on_success():
 77            Reporter.objects.filter(first_name="Alice").delete()
 78
 79        self.assertQuerysetEqual(Reporter.objects.all(), [])
 80
 81    @skipUnlessDBFeature('supports_transactions')
 82    def test_commit_on_success_exit(self):
 83        with transaction.autocommit():
 84            with transaction.commit_on_success():
 85                Reporter.objects.create(first_name="Bobby", last_name="Tables")
 86
 87            # Much more formal
 88            r = Reporter.objects.get()
 89            r.first_name = "Robert"
 90            r.save()
 91
 92        r = Reporter.objects.get()
 93        self.assertEqual(r.first_name, "Robert")
 94
 95    @skipUnlessDBFeature('supports_transactions')
 96    def test_manually_managed(self):
 97        """
 98        You can manually manage transactions if you really want to, but you
 99        have to remember to commit/rollback.
100        """
101        with transaction.commit_manually():
102            Reporter.objects.create(first_name="Libby", last_name="Holtzman")
103            transaction.commit()
104        self.assertEqual(Reporter.objects.count(), 1)
105
106    @skipUnlessDBFeature('supports_transactions')
107    def test_manually_managed_mistake(self):
108        """
109        If you forget, you'll get bad errors.
110        """
111        with self.assertRaises(transaction.TransactionManagementError):
112            with transaction.commit_manually():
113                Reporter.objects.create(first_name="Scott", last_name="Browning")
114
115    @skipUnlessDBFeature('supports_transactions')
116    def test_manually_managed_with_using(self):
117        """
118        The commit_manually function also works with a using argument.
119        """
120        with self.assertRaises(transaction.TransactionManagementError):
121            with transaction.commit_manually(using="default"):
122                Reporter.objects.create(first_name="Walter", last_name="Cronkite")
123
124    @skipUnlessDBFeature('requires_rollback_on_dirty_transaction')
125    def test_bad_sql(self):
126        """
127        Regression for #11900: If a block wrapped by commit_on_success
128        writes a transaction that can't be committed, that transaction should
129        be rolled back. The bug is only visible using the psycopg2 backend,
130        though the fix is generally a good idea.
131        """
132        with self.assertRaises(IntegrityError):
133            with transaction.commit_on_success():
134                cursor = connection.cursor()
135                cursor.execute("INSERT INTO transactions_reporter (first_name, last_name) VALUES ('Douglas', 'Adams');")
136                transaction.set_dirty()
137        transaction.rollback()