old_contents: """Unit tests for disk_usage_checker.py."""
  
  # standard library
  import argparse
  import unittest
  from unittest.mock import MagicMock
  
  # py3tester coverage target
  __test_target__ = 'delphi.operations.disk_usage_checker'
  
  
  class UnitTests(unittest.TestCase):
    """Basic unit tests."""
  
    def setUp(self):
      self.df_command = MagicMock()
      self.df_command.run.return_value = (
        'Filesystem  Size  Used Avail Use% Mounted on\n'
        '/dev/sda1   477M  168M  281M  38% /home\n'
        '/dev/sdb2   100M   90M   10M  90% /mnt/shared\n'
      )
      self.checker = DiskUsageChecker(self.df_command)
  
    def test_get_argument_parser(self):
      """An ArgumentParser should be returned."""
      self.assertIsInstance(get_argument_parser(), argparse.ArgumentParser)
  
    def test_validate_args(self):
      """Arguments should be validated."""
  
      with self.subTest(name='negative limit'):
        with self.assertRaises(InvalidArgsException):
          validate_args(MagicMock(limit=-1))
  
      with self.subTest(name='huge limit'):
        with self.assertRaises(InvalidArgsException):
          validate_args(MagicMock(limit=101))
  
      with self.subTest(name='valid limit'):
        self.assertEqual(validate_args(MagicMock(limit=75)), (75,))
  
    def test_disk_usage_checker_new_instance(self):
      """Acquire a production-ready instance."""
      self.assertIsInstance(DiskUsageChecker.new_instance(), DiskUsageChecker)
  
    def test_check_all(self):
      """Acquire a production-ready instance."""
  
      with self.subTest(name='all under'):
        text, result = self.checker.check_all(97)
        self.assertTrue(result)
  
      with self.subTest(name='mixed'):
        text, result = self.checker.check_all(50)
        self.assertFalse(result)
  
      with self.subTest(name='all over'):
        text, result = self.checker.check_all(20)
        self.assertFalse(result)
  
    def test_raise_if_any_over_limit(self):
      """Raise when the limit is exceeded."""
  
      with self.subTest(name='check pass'):
        self.assertIsNone(self.checker.raise_if_exceeds(95))
  
      with self.subTest(name='check fail'):
        with self.assertRaises(DiskUsageException):
          self.checker.raise_if_exceeds(50)
  
new_contents: """Unit tests for disk_usage_checker.py."""
  
  # standard library
  import argparse
  import unittest
  from unittest.mock import MagicMock
  
  # py3tester coverage target
  __test_target__ = 'delphi.operations.disk_usage_checker'
  
  
  class UnitTests(unittest.TestCase):
    """Basic unit tests."""
  
    def setUp(self):
      self.df_command = MagicMock()
      self.df_command.run.return_value = (
        'Filesystem  Size  Used Avail Use% Mounted on\n'
        '/dev/sda1   477M  168M  281M  38% /home\n'
        '/dev/sdb2   100M   90M   10M  90% /mnt/shared\n'
      )
      self.checker = DiskUsageChecker(self.df_command)
  
    def test_get_argument_parser(self):
      """An ArgumentParser should be returned."""
      self.assertIsInstance(get_argument_parser(), argparse.ArgumentParser)
  
    def test_validate_args(self):
      """Arguments should be validated."""
  
      with self.subTest(name='negative limit'):
        with self.assertRaises(InvalidArgsException):
          validate_args(MagicMock(limit=-1))
  
      with self.subTest(name='huge limit'):
        with self.assertRaises(InvalidArgsException):
          validate_args(MagicMock(limit=101))
  
      with self.subTest(name='valid limit'):
        self.assertEqual(validate_args(MagicMock(limit=75)), (75,))
  
    def test_disk_usage_checker_new_instance(self):
      """Acquire a production-ready instance."""
      self.assertIsInstance(DiskUsageChecker.new_instance(), DiskUsageChecker)
  
    def test_check_all(self):
      """Test all combinations of usage scenarios."""
  
      with self.subTest(name='all under'):
        text, result = self.checker.check_all(97)
        self.assertTrue(result)
  
      with self.subTest(name='mixed'):
        text, result = self.checker.check_all(50)
        self.assertFalse(result)
  
      with self.subTest(name='all over'):
        text, result = self.checker.check_all(20)
        self.assertFalse(result)
  
    def test_raise_if_any_over_limit(self):
      """Raise when the limit is exceeded."""
  
      with self.subTest(name='check pass'):
        self.assertIsNone(self.checker.raise_if_exceeds(95))
  
      with self.subTest(name='check fail'):
        with self.assertRaises(DiskUsageException):
          self.checker.raise_if_exceeds(50)
  
subject: fix copypasta in test docstring