Reorganized backends tests.

tests/backends/postgresql/test_creation.py

@@ -0,0 +1,95 @@
+import unittest
+from contextlib import contextmanager
+from io import StringIO
+from unittest import mock
+
+from django.db import connection
+from django.db.backends.base.creation import BaseDatabaseCreation
+from django.db.utils import DatabaseError
+from django.test import SimpleTestCase
+
+try:
+    import psycopg2  # NOQA
+except ImportError:
+    pass
+else:
+    from psycopg2 import errorcodes
+    from django.db.backends.postgresql.creation import DatabaseCreation
+
+
+@unittest.skipUnless(connection.vendor == 'postgresql', 'PostgreSQL tests')
+class DatabaseCreationTests(SimpleTestCase):
+
+    @contextmanager
+    def changed_test_settings(self, **kwargs):
+        settings = connection.settings_dict['TEST']
+        saved_values = {}
+        for name in kwargs:
+            if name in settings:
+                saved_values[name] = settings[name]
+
+        for name, value in kwargs.items():
+            settings[name] = value
+        try:
+            yield
+        finally:
+            for name, value in kwargs.items():
+                if name in saved_values:
+                    settings[name] = saved_values[name]
+                else:
+                    del settings[name]
+
+    def check_sql_table_creation_suffix(self, settings, expected):
+        with self.changed_test_settings(**settings):
+            creation = DatabaseCreation(connection)
+            suffix = creation.sql_table_creation_suffix()
+            self.assertEqual(suffix, expected)
+
+    def test_sql_table_creation_suffix_with_none_settings(self):
+        settings = {'CHARSET': None, 'TEMPLATE': None}
+        self.check_sql_table_creation_suffix(settings, "")
+
+    def test_sql_table_creation_suffix_with_encoding(self):
+        settings = {'CHARSET': 'UTF8'}
+        self.check_sql_table_creation_suffix(settings, "WITH ENCODING 'UTF8'")
+
+    def test_sql_table_creation_suffix_with_template(self):
+        settings = {'TEMPLATE': 'template0'}
+        self.check_sql_table_creation_suffix(settings, 'WITH TEMPLATE "template0"')
+
+    def test_sql_table_creation_suffix_with_encoding_and_template(self):
+        settings = {'CHARSET': 'UTF8', 'TEMPLATE': 'template0'}
+        self.check_sql_table_creation_suffix(settings, '''WITH ENCODING 'UTF8' TEMPLATE "template0"''')
+
+    def _execute_raise_database_already_exists(self, cursor, parameters, keepdb=False):
+        error = DatabaseError('database %s already exists' % parameters['dbname'])
+        error.pgcode = errorcodes.DUPLICATE_DATABASE
+        raise DatabaseError() from error
+
+    def _execute_raise_permission_denied(self, cursor, parameters, keepdb=False):
+        error = DatabaseError('permission denied to create database')
+        error.pgcode = errorcodes.INSUFFICIENT_PRIVILEGE
+        raise DatabaseError() from error
+
+    def patch_test_db_creation(self, execute_create_test_db):
+        return mock.patch.object(BaseDatabaseCreation, '_execute_create_test_db', execute_create_test_db)
+
+    @mock.patch('sys.stdout', new_callable=StringIO)
+    @mock.patch('sys.stderr', new_callable=StringIO)
+    def test_create_test_db(self, *mocked_objects):
+        creation = DatabaseCreation(connection)
+        # Simulate test database creation raising "database already exists"
+        with self.patch_test_db_creation(self._execute_raise_database_already_exists):
+            with mock.patch('builtins.input', return_value='no'):
+                with self.assertRaises(SystemExit):
+                    # SystemExit is raised if the user answers "no" to the
+                    # prompt asking if it's okay to delete the test database.
+                    creation._create_test_db(verbosity=0, autoclobber=False, keepdb=False)
+            # "Database already exists" error is ignored when keepdb is on
+            creation._create_test_db(verbosity=0, autoclobber=False, keepdb=True)
+        # Simulate test database creation raising unexpected error
+        with self.patch_test_db_creation(self._execute_raise_permission_denied):
+            with self.assertRaises(SystemExit):
+                creation._create_test_db(verbosity=0, autoclobber=False, keepdb=False)
+            with self.assertRaises(SystemExit):
+                creation._create_test_db(verbosity=0, autoclobber=False, keepdb=True)