text: import os
  
  from admin_scripts.tests import AdminScriptTestCase
  
  from django.apps import apps
  from django.core import management
  from django.core.management import BaseCommand, CommandError, find_commands
  from django.core.management.utils import find_command, popen_wrapper
  from django.db import connection
  from django.test import SimpleTestCase, override_settings
  from django.test.utils import captured_stderr, extend_sys_path
  from django.utils import translation
  from django.utils._os import upath
  from django.utils.six import StringIO
  
  
  # A minimal set of apps to avoid system checks running on all apps.
  @override_settings(
      INSTALLED_APPS=[
          'django.contrib.auth',
          'django.contrib.contenttypes',
          'user_commands',
      ],
  )
  class CommandTests(SimpleTestCase):
      def test_command(self):
          out = StringIO()
          management.call_command('dance', stdout=out)
          self.assertIn("I don't feel like dancing Rock'n'Roll.\n", out.getvalue())
  
      def test_command_style(self):
          out = StringIO()
          management.call_command('dance', style='Jive', stdout=out)
          self.assertIn("I don't feel like dancing Jive.\n", out.getvalue())
          # Passing options as arguments also works (thanks argparse)
          management.call_command('dance', '--style', 'Jive', stdout=out)
          self.assertIn("I don't feel like dancing Jive.\n", out.getvalue())
  
      def test_language_preserved(self):
          out = StringIO()
          with translation.override('fr'):
              management.call_command('dance', stdout=out)
              self.assertEqual(translation.get_language(), 'fr')
  
      def test_explode(self):
          """ Test that an unknown command raises CommandError """
          with self.assertRaises(CommandError):
              management.call_command(('explode',))
  
      def test_system_exit(self):
          """ Exception raised in a command should raise CommandError with
              call_command, but SystemExit when run from command line
          """
          with self.assertRaises(CommandError):
              management.call_command('dance', example="raise")
          with captured_stderr() as stderr, self.assertRaises(SystemExit):
              management.ManagementUtility(['manage.py', 'dance', '--example=raise']).execute()
          self.assertIn("CommandError", stderr.getvalue())
  
      def test_deactivate_locale_set(self):
          # Deactivate translation when set to true
          out = StringIO()
          with translation.override('pl'):
              management.call_command('leave_locale_alone_false', stdout=out)
              self.assertEqual(out.getvalue(), "")
  
      def test_configured_locale_preserved(self):
          # Leaves locale from settings when set to false
          out = StringIO()
          with translation.override('pl'):
              management.call_command('leave_locale_alone_true', stdout=out)
              self.assertEqual(out.getvalue(), "pl\n")
  
      def test_find_command_without_PATH(self):
          """
          find_command should still work when the PATH environment variable
          doesn't exist (#22256).
          """
          current_path = os.environ.pop('PATH', None)
  
          try:
              self.assertIsNone(find_command('_missing_'))
          finally:
              if current_path is not None:
                  os.environ['PATH'] = current_path
  
      def test_discover_commands_in_eggs(self):
          """
          Test that management commands can also be loaded from Python eggs.
          """
          egg_dir = '%s/eggs' % os.path.dirname(upath(__file__))
          egg_name = '%s/basic.egg' % egg_dir
          with extend_sys_path(egg_name):
              with self.settings(INSTALLED_APPS=['commandegg']):
                  cmds = find_commands(os.path.join(apps.get_app_config('commandegg').path, 'management'))
          self.assertEqual(cmds, ['eggcommand'])
  
      def test_call_command_option_parsing(self):
          """
          When passing the long option name to call_command, the available option
          key is the option dest name (#22985).
          """
          out = StringIO()
          management.call_command('dance', stdout=out, opt_3=True)
          self.assertIn("option3", out.getvalue())
          self.assertNotIn("opt_3", out.getvalue())
          self.assertNotIn("opt-3", out.getvalue())
  
      def test_call_command_option_parsing_non_string_arg(self):
          """
          It should be possible to pass non-string arguments to call_command.
          """
          out = StringIO()
          management.call_command('dance', 1, verbosity=0, stdout=out)
          self.assertIn("You passed 1 as a positional argument.", out.getvalue())
  
      def test_calling_a_command_with_only_empty_parameter_should_ends_gracefully(self):
          out = StringIO()
          management.call_command('hal', "--empty", stdout=out)
          self.assertIn("Dave, I can't do that.\n", out.getvalue())
  
      def test_calling_command_with_app_labels_and_parameters_should_be_ok(self):
          out = StringIO()
          management.call_command('hal', 'myapp', "--verbosity", "3", stdout=out)
          self.assertIn("Dave, my mind is going. I can feel it. I can feel it.\n", out.getvalue())
  
      def test_calling_command_with_parameters_and_app_labels_at_the_end_should_be_ok(self):
          out = StringIO()
          management.call_command('hal', "--verbosity", "3", "myapp", stdout=out)
          self.assertIn("Dave, my mind is going. I can feel it. I can feel it.\n", out.getvalue())
  
      def test_calling_a_command_with_no_app_labels_and_parameters_should_raise_a_command_error(self):
          out = StringIO()
          with self.assertRaises(CommandError):
              management.call_command('hal', stdout=out)
  
      def test_output_transaction(self):
          out = StringIO()
          management.call_command('transaction', stdout=out, no_color=True)
          output = out.getvalue().strip()
          self.assertTrue(output.startswith(connection.ops.start_transaction_sql()))
          self.assertTrue(output.endswith(connection.ops.end_transaction_sql()))
  
      def test_call_command_no_checks(self):
          """
          By default, call_command should not trigger the check framework, unless
          specifically asked.
          """
          self.counter = 0
  
          def patched_check(self_, **kwargs):
              self.counter = self.counter + 1
  
          saved_check = BaseCommand.check
          BaseCommand.check = patched_check
          try:
              management.call_command("dance", verbosity=0)
              self.assertEqual(self.counter, 0)
              management.call_command("dance", verbosity=0, skip_checks=False)
              self.assertEqual(self.counter, 1)
          finally:
              BaseCommand.check = saved_check
  
  
  class CommandRunTests(AdminScriptTestCase):
      """
      Tests that need to run by simulating the command line, not by call_command.
      """
      def tearDown(self):
          self.remove_settings('settings.py')
  
      def test_script_prefix_set_in_commands(self):
          self.write_settings('settings.py', apps=['user_commands'], sdict={
              'ROOT_URLCONF': '"user_commands.urls"',
              'FORCE_SCRIPT_NAME': '"/PREFIX/"',
          })
          out, err = self.run_manage(['reverse_url'])
          self.assertNoOutput(err)
          self.assertEqual(out.strip(), '/PREFIX/some/url/')
  
  
  class UtilsTests(SimpleTestCase):
  
      def test_no_existent_external_program(self):
          with self.assertRaises(CommandError):
              popen_wrapper(['a_42_command_that_doesnt_exist_42'])
  