text: """Test script for the dumbdbm module
     Original by Roger E. Masse
  """
  
  import contextlib
  import io
  import operator
  import os
  import stat
  import unittest
  import dbm.dumb as dumbdbm
  from test import support
  from functools import partial
  import sys
  _fname = support.TESTFN
  
  def _delete_files():
      for ext in [".dir", ".dat", ".bak"]:
          try:
              os.unlink(_fname + ext)
          except OSError:
              pass
  
  class DumbDBMTestCase(unittest.TestCase):
      _dict = {b'0': b'',
               b'a': b'Python:',
               b'b': b'Programming',
               b'c': b'the',
               b'd': b'way',
               b'f': b'Guido',
               b'g': b'intended',
               '\u00fc'.encode('utf-8') : b'!',
               }
  
      def test_dumbdbm_creation(self):
          with contextlib.closing(dumbdbm.open(_fname, 'c')) as f:
              self.assertEqual(list(f.keys()), [])
              for key in self._dict:
                  f[key] = self._dict[key]
              self.read_helper(f)
  
      @unittest.skipUnless(hasattr(os, 'umask'), 'test needs os.umask()')
      def test_dumbdbm_creation_mode(self):
          try:
              old_umask = os.umask(0o002)
              f = dumbdbm.open(_fname, 'c', 0o637)
              f.close()
          finally:
              os.umask(old_umask)
  
          expected_mode = 0o635
          if os.name != 'posix':
              # Windows only supports setting the read-only attribute.
              # This shouldn't fail, but doesn't work like Unix either.
              expected_mode = 0o666
  
          import stat
          st = os.stat(_fname + '.dat')
          self.assertEqual(stat.S_IMODE(st.st_mode), expected_mode)
          st = os.stat(_fname + '.dir')
          self.assertEqual(stat.S_IMODE(st.st_mode), expected_mode)
  
      def test_close_twice(self):
          f = dumbdbm.open(_fname)
          f[b'a'] = b'b'
          self.assertEqual(f[b'a'], b'b')
          f.close()
          f.close()
  
      def test_dumbdbm_modification(self):
          self.init_db()
          with contextlib.closing(dumbdbm.open(_fname, 'w')) as f:
              self._dict[b'g'] = f[b'g'] = b"indented"
              self.read_helper(f)
              # setdefault() works as in the dict interface
              self.assertEqual(f.setdefault(b'xxx', b'foo'), b'foo')
              self.assertEqual(f[b'xxx'], b'foo')
  
      def test_dumbdbm_read(self):
          self.init_db()
          with contextlib.closing(dumbdbm.open(_fname, 'r')) as f:
              self.read_helper(f)
              with self.assertRaisesRegex(dumbdbm.error,
                                      'The database is opened for reading only'):
                  f[b'g'] = b'x'
              with self.assertRaisesRegex(dumbdbm.error,
                                      'The database is opened for reading only'):
                  del f[b'a']
              # get() works as in the dict interface
              self.assertEqual(f.get(b'a'), self._dict[b'a'])
              self.assertEqual(f.get(b'xxx', b'foo'), b'foo')
              self.assertIsNone(f.get(b'xxx'))
              with self.assertRaises(KeyError):
                  f[b'xxx']
  
      def test_dumbdbm_keys(self):
          self.init_db()
          with contextlib.closing(dumbdbm.open(_fname)) as f:
              keys = self.keys_helper(f)
  
      def test_write_contains(self):
          with contextlib.closing(dumbdbm.open(_fname)) as f:
              f[b'1'] = b'hello'
              self.assertIn(b'1', f)
  
      def test_write_write_read(self):
          # test for bug #482460
          with contextlib.closing(dumbdbm.open(_fname)) as f:
              f[b'1'] = b'hello'
              f[b'1'] = b'hello2'
          with contextlib.closing(dumbdbm.open(_fname)) as f:
              self.assertEqual(f[b'1'], b'hello2')
  
      def test_str_read(self):
          self.init_db()
          with contextlib.closing(dumbdbm.open(_fname, 'r')) as f:
              self.assertEqual(f['\u00fc'], self._dict['\u00fc'.encode('utf-8')])
  
      def test_str_write_contains(self):
          self.init_db()
          with contextlib.closing(dumbdbm.open(_fname)) as f:
              f['\u00fc'] = b'!'
              f['1'] = 'a'
          with contextlib.closing(dumbdbm.open(_fname, 'r')) as f:
              self.assertIn('\u00fc', f)
              self.assertEqual(f['\u00fc'.encode('utf-8')],
                               self._dict['\u00fc'.encode('utf-8')])
              self.assertEqual(f[b'1'], b'a')
  
      def test_line_endings(self):
          # test for bug #1172763: dumbdbm would die if the line endings
          # weren't what was expected.
          with contextlib.closing(dumbdbm.open(_fname)) as f:
              f[b'1'] = b'hello'
              f[b'2'] = b'hello2'
  
          # Mangle the file by changing the line separator to Windows or Unix
          with io.open(_fname + '.dir', 'rb') as file:
              data = file.read()
          if os.linesep == '\n':
              data = data.replace(b'\n', b'\r\n')
          else:
              data = data.replace(b'\r\n', b'\n')
          with io.open(_fname + '.dir', 'wb') as file:
              file.write(data)
  
          f = dumbdbm.open(_fname)
          self.assertEqual(f[b'1'], b'hello')
          self.assertEqual(f[b'2'], b'hello2')
  
  
      def read_helper(self, f):
          keys = self.keys_helper(f)
          for key in self._dict:
              self.assertEqual(self._dict[key], f[key])
  
      def init_db(self):
          with contextlib.closing(dumbdbm.open(_fname, 'n')) as f:
              for k in self._dict:
                  f[k] = self._dict[k]
  
      def keys_helper(self, f):
          keys = sorted(f.keys())
          dkeys = sorted(self._dict.keys())
          self.assertEqual(keys, dkeys)
          return keys
  
      # Perform randomized operations.  This doesn't make assumptions about
      # what *might* fail.
      def test_random(self):
          import random
          d = {}  # mirror the database
          for dummy in range(5):
              with contextlib.closing(dumbdbm.open(_fname)) as f:
                  for dummy in range(100):
                      k = random.choice('abcdefghijklm')
                      if random.random() < 0.2:
                          if k in d:
                              del d[k]
                              del f[k]
                      else:
                          v = random.choice((b'a', b'b', b'c')) * random.randrange(10000)
                          d[k] = v
                          f[k] = v
                          self.assertEqual(f[k], v)
  
              with contextlib.closing(dumbdbm.open(_fname)) as f:
                  expected = sorted((k.encode("latin-1"), v) for k, v in d.items())
                  got = sorted(f.items())
                  self.assertEqual(expected, got)
  
      def test_context_manager(self):
          with dumbdbm.open(_fname, 'c') as db:
              db["dumbdbm context manager"] = "context manager"
  
          with dumbdbm.open(_fname, 'r') as db:
              self.assertEqual(list(db.keys()), [b"dumbdbm context manager"])
  
          with self.assertRaises(dumbdbm.error):
              db.keys()
  
      def test_check_closed(self):
          f = dumbdbm.open(_fname, 'c')
          f.close()
  
          for meth in (partial(operator.delitem, f),
                       partial(operator.setitem, f, 'b'),
                       partial(operator.getitem, f),
                       partial(operator.contains, f)):
              with self.assertRaises(dumbdbm.error) as cm:
                  meth('test')
              self.assertEqual(str(cm.exception),
                               "DBM object has already been closed")
  
          for meth in (operator.methodcaller('keys'),
                       operator.methodcaller('iterkeys'),
                       operator.methodcaller('items'),
                       len):
              with self.assertRaises(dumbdbm.error) as cm:
                  meth(f)
              self.assertEqual(str(cm.exception),
                               "DBM object has already been closed")
  
      def test_create_new(self):
          with dumbdbm.open(_fname, 'n') as f:
              for k in self._dict:
                  f[k] = self._dict[k]
  
          with dumbdbm.open(_fname, 'n') as f:
              self.assertEqual(f.keys(), [])
  
      def test_eval(self):
          with open(_fname + '.dir', 'w') as stream:
              stream.write("str(print('Hacked!')), 0\n")
          with support.captured_stdout() as stdout:
              with self.assertRaises(ValueError):
                  with dumbdbm.open(_fname) as f:
                      pass
              self.assertEqual(stdout.getvalue(), '')
  
      def test_missing_data(self):
          for value in ('r', 'w'):
              _delete_files()
              with self.assertRaises(FileNotFoundError):
                  dumbdbm.open(_fname, value)
              self.assertFalse(os.path.exists(_fname + '.dir'))
              self.assertFalse(os.path.exists(_fname + '.bak'))
  
      def test_missing_index(self):
          with dumbdbm.open(_fname, 'n') as f:
              pass
          os.unlink(_fname + '.dir')
          for value in ('r', 'w'):
              with self.assertRaises(FileNotFoundError):
                  dumbdbm.open(_fname, value)
              self.assertFalse(os.path.exists(_fname + '.dir'))
              self.assertFalse(os.path.exists(_fname + '.bak'))
  
      def test_invalid_flag(self):
          for flag in ('x', 'rf', None):
              with self.assertRaisesRegex(ValueError,
                                          "Flag must be one of "
                                          "'r', 'w', 'c', or 'n'"):
                  dumbdbm.open(_fname, flag)
  
      def test_readonly_files(self):
          with support.temp_dir() as dir:
              fname = os.path.join(dir, 'db')
              with dumbdbm.open(fname, 'n') as f:
                  self.assertEqual(list(f.keys()), [])
                  for key in self._dict:
                      f[key] = self._dict[key]
              os.chmod(fname + ".dir", stat.S_IRUSR)
              os.chmod(fname + ".dat", stat.S_IRUSR)
              os.chmod(dir, stat.S_IRUSR|stat.S_IXUSR)
              with dumbdbm.open(fname, 'r') as f:
                  self.assertEqual(sorted(f.keys()), sorted(self._dict))
                  f.close()  # don't write
              if sys.platform == 'OpenVMS':
                  # required for OpenVMS
                  os.chmod(dir, stat.S_IRWXU)
                  os.chmod(fname + ".dir", stat.S_IRWXU)
                  os.chmod(fname + ".dat", stat.S_IRWXU)
  
  
      @unittest.skipUnless(support.TESTFN_NONASCII,
                           'requires OS support of non-ASCII encodings')
      def test_nonascii_filename(self):
          filename = support.TESTFN_NONASCII
          for suffix in ['.dir', '.dat', '.bak']:
              self.addCleanup(support.unlink, filename + suffix)
          with dumbdbm.open(filename, 'c') as db:
              db[b'key'] = b'value'
          self.assertTrue(os.path.exists(filename + '.dat'))
          self.assertTrue(os.path.exists(filename + '.dir'))
          with dumbdbm.open(filename, 'r') as db:
              self.assertEqual(list(db.keys()), [b'key'])
              self.assertTrue(b'key' in db)
              self.assertEqual(db[b'key'], b'value')
  
      def tearDown(self):
          _delete_files()
  
      def setUp(self):
          _delete_files()
  
  
  if __name__ == "__main__":
      unittest.main()
  