text: """Unit tests for memory-based file-like objects.
  StringIO -- for unicode strings
  BytesIO -- for bytes
  """
  
  from __future__ import unicode_literals
  from __future__ import print_function
  from __future__ import absolute_import
  
  import unittest
  from test import test_support as support
  
  import io
  import _pyio as pyio
  import pickle
  
  class MemorySeekTestMixin:
  
      def testInit(self):
          buf = self.buftype("1234567890")
          bytesIo = self.ioclass(buf)
  
      def testRead(self):
          buf = self.buftype("1234567890")
          bytesIo = self.ioclass(buf)
  
          self.assertEqual(buf[:1], bytesIo.read(1))
          self.assertEqual(buf[1:5], bytesIo.read(4))
          self.assertEqual(buf[5:], bytesIo.read(900))
          self.assertEqual(self.EOF, bytesIo.read())
  
      def testReadNoArgs(self):
          buf = self.buftype("1234567890")
          bytesIo = self.ioclass(buf)
  
          self.assertEqual(buf, bytesIo.read())
          self.assertEqual(self.EOF, bytesIo.read())
  
      def testSeek(self):
          buf = self.buftype("1234567890")
          bytesIo = self.ioclass(buf)
  
          bytesIo.read(5)
          bytesIo.seek(0)
          self.assertEqual(buf, bytesIo.read())
  
          bytesIo.seek(3)
          self.assertEqual(buf[3:], bytesIo.read())
          self.assertRaises(TypeError, bytesIo.seek, 0.0)
  
      def testTell(self):
          buf = self.buftype("1234567890")
          bytesIo = self.ioclass(buf)
  
          self.assertEqual(0, bytesIo.tell())
          bytesIo.seek(5)
          self.assertEqual(5, bytesIo.tell())
          bytesIo.seek(10000)
          self.assertEqual(10000, bytesIo.tell())
  
  
  class MemoryTestMixin:
  
      def test_detach(self):
          buf = self.ioclass()
          self.assertRaises(self.UnsupportedOperation, buf.detach)
  
      def write_ops(self, f, t):
          self.assertEqual(f.write(t("blah.")), 5)
          self.assertEqual(f.seek(0), 0)
          self.assertEqual(f.write(t("Hello.")), 6)
          self.assertEqual(f.tell(), 6)
          self.assertEqual(f.seek(5), 5)
          self.assertEqual(f.tell(), 5)
          self.assertEqual(f.write(t(" world\n\n\n")), 9)
          self.assertEqual(f.seek(0), 0)
          self.assertEqual(f.write(t("h")), 1)
          self.assertEqual(f.truncate(12), 12)
          self.assertEqual(f.tell(), 1)
  
      def test_write(self):
          buf = self.buftype("hello world\n")
          memio = self.ioclass(buf)
  
          self.write_ops(memio, self.buftype)
          self.assertEqual(memio.getvalue(), buf)
          memio = self.ioclass()
          self.write_ops(memio, self.buftype)
          self.assertEqual(memio.getvalue(), buf)
          self.assertRaises(TypeError, memio.write, None)
          memio.close()
          self.assertRaises(ValueError, memio.write, self.buftype(""))
  
      def test_writelines(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass()
  
          self.assertEqual(memio.writelines([buf] * 100), None)
          self.assertEqual(memio.getvalue(), buf * 100)
          memio.writelines([])
          self.assertEqual(memio.getvalue(), buf * 100)
          memio = self.ioclass()
          self.assertRaises(TypeError, memio.writelines, [buf] + [1])
          self.assertEqual(memio.getvalue(), buf)
          self.assertRaises(TypeError, memio.writelines, None)
          memio.close()
          self.assertRaises(ValueError, memio.writelines, [])
  
      def test_writelines_error(self):
          memio = self.ioclass()
          def error_gen():
              yield self.buftype('spam')
              raise KeyboardInterrupt
  
          self.assertRaises(KeyboardInterrupt, memio.writelines, error_gen())
  
      def test_truncate(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertRaises(ValueError, memio.truncate, -1)
          memio.seek(6)
          self.assertEqual(memio.truncate(), 6)
          self.assertEqual(memio.getvalue(), buf[:6])
          self.assertEqual(memio.truncate(4), 4)
          self.assertEqual(memio.getvalue(), buf[:4])
          # truncate() accepts long objects
          self.assertEqual(memio.truncate(4L), 4)
          self.assertEqual(memio.getvalue(), buf[:4])
          self.assertEqual(memio.tell(), 6)
          memio.seek(0, 2)
          memio.write(buf)
          self.assertEqual(memio.getvalue(), buf[:4] + buf)
          pos = memio.tell()
          self.assertEqual(memio.truncate(None), pos)
          self.assertEqual(memio.tell(), pos)
          self.assertRaises(TypeError, memio.truncate, '0')
          memio.close()
          self.assertRaises(ValueError, memio.truncate, 0)
  
      def test_init(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
          self.assertEqual(memio.getvalue(), buf)
          memio = self.ioclass(None)
          self.assertEqual(memio.getvalue(), self.EOF)
          memio.__init__(buf * 2)
          self.assertEqual(memio.getvalue(), buf * 2)
          memio.__init__(buf)
          self.assertEqual(memio.getvalue(), buf)
  
      def test_read(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.read(0), self.EOF)
          self.assertEqual(memio.read(1), buf[:1])
          # read() accepts long objects
          self.assertEqual(memio.read(4L), buf[1:5])
          self.assertEqual(memio.read(900), buf[5:])
          self.assertEqual(memio.read(), self.EOF)
          memio.seek(0)
          self.assertEqual(memio.read(), buf)
          self.assertEqual(memio.read(), self.EOF)
          self.assertEqual(memio.tell(), 10)
          memio.seek(0)
          self.assertEqual(memio.read(-1), buf)
          memio.seek(0)
          self.assertEqual(type(memio.read()), type(buf))
          memio.seek(100)
          self.assertEqual(type(memio.read()), type(buf))
          memio.seek(0)
          self.assertEqual(memio.read(None), buf)
          self.assertRaises(TypeError, memio.read, '')
          memio.close()
          self.assertRaises(ValueError, memio.read)
  
      def test_readline(self):
          buf = self.buftype("1234567890\n")
          memio = self.ioclass(buf * 2)
  
          self.assertEqual(memio.readline(0), self.EOF)
          self.assertEqual(memio.readline(), buf)
          self.assertEqual(memio.readline(), buf)
          self.assertEqual(memio.readline(), self.EOF)
          memio.seek(0)
          self.assertEqual(memio.readline(5), buf[:5])
          # readline() accepts long objects
          self.assertEqual(memio.readline(5L), buf[5:10])
          self.assertEqual(memio.readline(5), buf[10:15])
          memio.seek(0)
          self.assertEqual(memio.readline(-1), buf)
          memio.seek(0)
          self.assertEqual(memio.readline(0), self.EOF)
  
          buf = self.buftype("1234567890\n")
          memio = self.ioclass((buf * 3)[:-1])
          self.assertEqual(memio.readline(), buf)
          self.assertEqual(memio.readline(), buf)
          self.assertEqual(memio.readline(), buf[:-1])
          self.assertEqual(memio.readline(), self.EOF)
          memio.seek(0)
          self.assertEqual(type(memio.readline()), type(buf))
          self.assertEqual(memio.readline(), buf)
          self.assertRaises(TypeError, memio.readline, '')
          memio.close()
          self.assertRaises(ValueError,  memio.readline)
  
      def test_readlines(self):
          buf = self.buftype("1234567890\n")
          memio = self.ioclass(buf * 10)
  
          self.assertEqual(memio.readlines(), [buf] * 10)
          memio.seek(5)
          self.assertEqual(memio.readlines(), [buf[5:]] + [buf] * 9)
          memio.seek(0)
          # readlines() accepts long objects
          self.assertEqual(memio.readlines(15L), [buf] * 2)
          memio.seek(0)
          self.assertEqual(memio.readlines(-1), [buf] * 10)
          memio.seek(0)
          self.assertEqual(memio.readlines(0), [buf] * 10)
          memio.seek(0)
          self.assertEqual(type(memio.readlines()[0]), type(buf))
          memio.seek(0)
          self.assertEqual(memio.readlines(None), [buf] * 10)
          self.assertRaises(TypeError, memio.readlines, '')
          memio.close()
          self.assertRaises(ValueError, memio.readlines)
  
      def test_iterator(self):
          buf = self.buftype("1234567890\n")
          memio = self.ioclass(buf * 10)
  
          self.assertEqual(iter(memio), memio)
          self.assertTrue(hasattr(memio, '__iter__'))
          self.assertTrue(hasattr(memio, 'next'))
          i = 0
          for line in memio:
              self.assertEqual(line, buf)
              i += 1
          self.assertEqual(i, 10)
          memio.seek(0)
          i = 0
          for line in memio:
              self.assertEqual(line, buf)
              i += 1
          self.assertEqual(i, 10)
          memio = self.ioclass(buf * 2)
          memio.close()
          self.assertRaises(ValueError, next, memio)
  
      def test_getvalue(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.getvalue(), buf)
          memio.read()
          self.assertEqual(memio.getvalue(), buf)
          self.assertEqual(type(memio.getvalue()), type(buf))
          memio = self.ioclass(buf * 1000)
          self.assertEqual(memio.getvalue()[-3:], self.buftype("890"))
          memio = self.ioclass(buf)
          memio.close()
          self.assertRaises(ValueError, memio.getvalue)
  
      def test_seek(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          memio.read(5)
          self.assertRaises(ValueError, memio.seek, -1)
          self.assertRaises(ValueError, memio.seek, 1, -1)
          self.assertRaises(ValueError, memio.seek, 1, 3)
          self.assertEqual(memio.seek(0), 0)
          self.assertEqual(memio.seek(0, 0), 0)
          self.assertEqual(memio.read(), buf)
          self.assertEqual(memio.seek(3), 3)
          # seek() accepts long objects
          self.assertEqual(memio.seek(3L), 3)
          self.assertEqual(memio.seek(0, 1), 3)
          self.assertEqual(memio.read(), buf[3:])
          self.assertEqual(memio.seek(len(buf)), len(buf))
          self.assertEqual(memio.read(), self.EOF)
          memio.seek(len(buf) + 1)
          self.assertEqual(memio.read(), self.EOF)
          self.assertEqual(memio.seek(0, 2), len(buf))
          self.assertEqual(memio.read(), self.EOF)
          memio.close()
          self.assertRaises(ValueError, memio.seek, 0)
  
      def test_overseek(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.seek(len(buf) + 1), 11)
          self.assertEqual(memio.read(), self.EOF)
          self.assertEqual(memio.tell(), 11)
          self.assertEqual(memio.getvalue(), buf)
          memio.write(self.EOF)
          self.assertEqual(memio.getvalue(), buf)
          memio.write(buf)
          self.assertEqual(memio.getvalue(), buf + self.buftype('\0') + buf)
  
      def test_tell(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.tell(), 0)
          memio.seek(5)
          self.assertEqual(memio.tell(), 5)
          memio.seek(10000)
          self.assertEqual(memio.tell(), 10000)
          memio.close()
          self.assertRaises(ValueError, memio.tell)
  
      def test_flush(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.flush(), None)
  
      def test_flags(self):
          memio = self.ioclass()
  
          self.assertEqual(memio.writable(), True)
          self.assertEqual(memio.readable(), True)
          self.assertEqual(memio.seekable(), True)
          self.assertEqual(memio.isatty(), False)
          self.assertEqual(memio.closed, False)
          memio.close()
          self.assertRaises(ValueError, memio.writable)
          self.assertRaises(ValueError, memio.readable)
          self.assertRaises(ValueError, memio.seekable)
          self.assertRaises(ValueError, memio.isatty)
          self.assertEqual(memio.closed, True)
  
      def test_subclassing(self):
          buf = self.buftype("1234567890")
          def test1():
              class MemIO(self.ioclass):
                  pass
              m = MemIO(buf)
              return m.getvalue()
          def test2():
              class MemIO(self.ioclass):
                  def __init__(me, a, b):
                      self.ioclass.__init__(me, a)
              m = MemIO(buf, None)
              return m.getvalue()
          self.assertEqual(test1(), buf)
          self.assertEqual(test2(), buf)
  
      def test_instance_dict_leak(self):
          # Test case for issue #6242.
          # This will be caught by regrtest.py -R if this leak.
          for _ in range(100):
              memio = self.ioclass()
              memio.foo = 1
  
      def test_pickling(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
          memio.foo = 42
          memio.seek(2)
  
          class PickleTestMemIO(self.ioclass):
              def __init__(me, initvalue, foo):
                  self.ioclass.__init__(me, initvalue)
                  me.foo = foo
              # __getnewargs__ is undefined on purpose. This checks that PEP 307
              # is used to provide pickling support.
  
          # Pickle expects the class to be on the module level. Here we use a
          # little hack to allow the PickleTestMemIO class to derive from
          # self.ioclass without having to define all combinations explicitly on
          # the module-level.
          import __main__
          PickleTestMemIO.__module__ = '__main__'
          PickleTestMemIO.__qualname__ = PickleTestMemIO.__name__
          __main__.PickleTestMemIO = PickleTestMemIO
          submemio = PickleTestMemIO(buf, 80)
          submemio.seek(2)
  
          # We only support pickle protocol 2 and onward since we use extended
          # __reduce__ API of PEP 307 to provide pickling support.
          for proto in range(2, pickle.HIGHEST_PROTOCOL + 1):
              for obj in (memio, submemio):
                  obj2 = pickle.loads(pickle.dumps(obj, protocol=proto))
                  self.assertEqual(obj.getvalue(), obj2.getvalue())
                  self.assertEqual(obj.__class__, obj2.__class__)
                  self.assertEqual(obj.foo, obj2.foo)
                  self.assertEqual(obj.tell(), obj2.tell())
                  obj.close()
                  self.assertRaises(ValueError, pickle.dumps, obj, proto)
          del __main__.PickleTestMemIO
  
  
  class PyBytesIOTest(MemoryTestMixin, MemorySeekTestMixin, unittest.TestCase):
      # Test _pyio.BytesIO; class also inherited for testing C implementation
  
      UnsupportedOperation = pyio.UnsupportedOperation
  
      @staticmethod
      def buftype(s):
          return s.encode("ascii")
      ioclass = pyio.BytesIO
      EOF = b""
  
      def test_read1(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertRaises(TypeError, memio.read1)
          self.assertEqual(memio.read(), buf)
  
      def test_readinto(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          b = bytearray(b"hello")
          self.assertEqual(memio.readinto(b), 5)
          self.assertEqual(b, b"12345")
          self.assertEqual(memio.readinto(b), 5)
          self.assertEqual(b, b"67890")
          self.assertEqual(memio.readinto(b), 0)
          self.assertEqual(b, b"67890")
          b = bytearray(b"hello world")
          memio.seek(0)
          self.assertEqual(memio.readinto(b), 10)
          self.assertEqual(b, b"1234567890d")
          b = bytearray(b"")
          memio.seek(0)
          self.assertEqual(memio.readinto(b), 0)
          self.assertEqual(b, b"")
          self.assertRaises(TypeError, memio.readinto, '')
          import array
          a = array.array(b'b', b"hello world")
          memio = self.ioclass(buf)
          memio.readinto(a)
          self.assertEqual(a.tostring(), b"1234567890d")
          memio.close()
          self.assertRaises(ValueError, memio.readinto, b)
          memio = self.ioclass(b"123")
          b = bytearray()
          memio.seek(42)
          memio.readinto(b)
          self.assertEqual(b, b"")
  
      def test_relative_seek(self):
          buf = self.buftype("1234567890")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.seek(-1, 1), 0)
          self.assertEqual(memio.seek(3, 1), 3)
          self.assertEqual(memio.seek(-4, 1), 0)
          self.assertEqual(memio.seek(-1, 2), 9)
          self.assertEqual(memio.seek(1, 1), 10)
          self.assertEqual(memio.seek(1, 2), 11)
          memio.seek(-3, 2)
          self.assertEqual(memio.read(), buf[-3:])
          memio.seek(0)
          memio.seek(1, 1)
          self.assertEqual(memio.read(), buf[1:])
  
      def test_unicode(self):
          memio = self.ioclass()
  
          self.assertRaises(TypeError, self.ioclass, "1234567890")
          self.assertRaises(TypeError, memio.write, "1234567890")
          self.assertRaises(TypeError, memio.writelines, ["1234567890"])
  
      def test_bytes_array(self):
          buf = b"1234567890"
          import array
          a = array.array(b'b', buf)
          memio = self.ioclass(a)
          self.assertEqual(memio.getvalue(), buf)
          self.assertEqual(memio.write(a), 10)
          self.assertEqual(memio.getvalue(), buf)
  
      def test_issue5449(self):
          buf = self.buftype("1234567890")
          self.ioclass(initial_bytes=buf)
          self.assertRaises(TypeError, self.ioclass, buf, foo=None)
  
  
  class TextIOTestMixin:
  
      def test_newlines_property(self):
          memio = self.ioclass(newline=None)
          # The C StringIO decodes newlines in write() calls, but the Python
          # implementation only does when reading.  This function forces them to
          # be decoded for testing.
          def force_decode():
              memio.seek(0)
              memio.read()
          self.assertEqual(memio.newlines, None)
          memio.write("a\n")
          force_decode()
          self.assertEqual(memio.newlines, "\n")
          memio.write("b\r\n")
          force_decode()
          self.assertEqual(memio.newlines, ("\n", "\r\n"))
          memio.write("c\rd")
          force_decode()
          self.assertEqual(memio.newlines, ("\r", "\n", "\r\n"))
  
      def test_relative_seek(self):
          memio = self.ioclass()
  
          self.assertRaises(IOError, memio.seek, -1, 1)
          self.assertRaises(IOError, memio.seek, 3, 1)
          self.assertRaises(IOError, memio.seek, -3, 1)
          self.assertRaises(IOError, memio.seek, -1, 2)
          self.assertRaises(IOError, memio.seek, 1, 1)
          self.assertRaises(IOError, memio.seek, 1, 2)
  
      def test_textio_properties(self):
          memio = self.ioclass()
  
          # These are just dummy values but we nevertheless check them for fear
          # of unexpected breakage.
          self.assertIsNone(memio.encoding)
          self.assertIsNone(memio.errors)
          self.assertFalse(memio.line_buffering)
  
      def test_newline_default(self):
          memio = self.ioclass("a\nb\r\nc\rd")
          self.assertEqual(list(memio), ["a\n", "b\r\n", "c\rd"])
          self.assertEqual(memio.getvalue(), "a\nb\r\nc\rd")
  
          memio = self.ioclass()
          self.assertEqual(memio.write("a\nb\r\nc\rd"), 8)
          memio.seek(0)
          self.assertEqual(list(memio), ["a\n", "b\r\n", "c\rd"])
          self.assertEqual(memio.getvalue(), "a\nb\r\nc\rd")
  
      def test_newline_none(self):
          # newline=None
          memio = self.ioclass("a\nb\r\nc\rd", newline=None)
          self.assertEqual(list(memio), ["a\n", "b\n", "c\n", "d"])
          memio.seek(0)
          self.assertEqual(memio.read(1), "a")
          self.assertEqual(memio.read(2), "\nb")
          self.assertEqual(memio.read(2), "\nc")
          self.assertEqual(memio.read(1), "\n")
          self.assertEqual(memio.getvalue(), "a\nb\nc\nd")
  
          memio = self.ioclass(newline=None)
          self.assertEqual(2, memio.write("a\n"))
          self.assertEqual(3, memio.write("b\r\n"))
          self.assertEqual(3, memio.write("c\rd"))
          memio.seek(0)
          self.assertEqual(memio.read(), "a\nb\nc\nd")
          self.assertEqual(memio.getvalue(), "a\nb\nc\nd")
  
          memio = self.ioclass("a\r\nb", newline=None)
          self.assertEqual(memio.read(3), "a\nb")
  
      def test_newline_empty(self):
          # newline=""
          memio = self.ioclass("a\nb\r\nc\rd", newline="")
          self.assertEqual(list(memio), ["a\n", "b\r\n", "c\r", "d"])
          memio.seek(0)
          self.assertEqual(memio.read(4), "a\nb\r")
          self.assertEqual(memio.read(2), "\nc")
          self.assertEqual(memio.read(1), "\r")
          self.assertEqual(memio.getvalue(), "a\nb\r\nc\rd")
  
          memio = self.ioclass(newline="")
          self.assertEqual(2, memio.write("a\n"))
          self.assertEqual(2, memio.write("b\r"))
          self.assertEqual(2, memio.write("\nc"))
          self.assertEqual(2, memio.write("\rd"))
          memio.seek(0)
          self.assertEqual(list(memio), ["a\n", "b\r\n", "c\r", "d"])
          self.assertEqual(memio.getvalue(), "a\nb\r\nc\rd")
  
      def test_newline_lf(self):
          # newline="\n"
          memio = self.ioclass("a\nb\r\nc\rd", newline="\n")
          self.assertEqual(list(memio), ["a\n", "b\r\n", "c\rd"])
          self.assertEqual(memio.getvalue(), "a\nb\r\nc\rd")
  
          memio = self.ioclass(newline="\n")
          self.assertEqual(memio.write("a\nb\r\nc\rd"), 8)
          memio.seek(0)
          self.assertEqual(list(memio), ["a\n", "b\r\n", "c\rd"])
          self.assertEqual(memio.getvalue(), "a\nb\r\nc\rd")
  
      def test_newline_cr(self):
          # newline="\r"
          memio = self.ioclass("a\nb\r\nc\rd", newline="\r")
          self.assertEqual(memio.read(), "a\rb\r\rc\rd")
          memio.seek(0)
          self.assertEqual(list(memio), ["a\r", "b\r", "\r", "c\r", "d"])
          self.assertEqual(memio.getvalue(), "a\rb\r\rc\rd")
  
          memio = self.ioclass(newline="\r")
          self.assertEqual(memio.write("a\nb\r\nc\rd"), 8)
          memio.seek(0)
          self.assertEqual(list(memio), ["a\r", "b\r", "\r", "c\r", "d"])
          memio.seek(0)
          self.assertEqual(memio.readlines(), ["a\r", "b\r", "\r", "c\r", "d"])
          self.assertEqual(memio.getvalue(), "a\rb\r\rc\rd")
  
      def test_newline_crlf(self):
          # newline="\r\n"
          memio = self.ioclass("a\nb\r\nc\rd", newline="\r\n")
          self.assertEqual(memio.read(), "a\r\nb\r\r\nc\rd")
          memio.seek(0)
          self.assertEqual(list(memio), ["a\r\n", "b\r\r\n", "c\rd"])
          memio.seek(0)
          self.assertEqual(memio.readlines(), ["a\r\n", "b\r\r\n", "c\rd"])
          self.assertEqual(memio.getvalue(), "a\r\nb\r\r\nc\rd")
  
          memio = self.ioclass(newline="\r\n")
          self.assertEqual(memio.write("a\nb\r\nc\rd"), 8)
          memio.seek(0)
          self.assertEqual(list(memio), ["a\r\n", "b\r\r\n", "c\rd"])
          self.assertEqual(memio.getvalue(), "a\r\nb\r\r\nc\rd")
  
      def test_issue5265(self):
          # StringIO can duplicate newlines in universal newlines mode
          memio = self.ioclass("a\r\nb\r\n", newline=None)
          self.assertEqual(memio.read(5), "a\nb\n")
          self.assertEqual(memio.getvalue(), "a\nb\n")
  
  
  class PyStringIOTest(MemoryTestMixin, MemorySeekTestMixin,
                       TextIOTestMixin, unittest.TestCase):
      buftype = unicode
      ioclass = pyio.StringIO
      UnsupportedOperation = pyio.UnsupportedOperation
      EOF = ""
  
      def test_lone_surrogates(self):
          # Issue #20424
          surrogate = unichr(0xd800)
          memio = self.ioclass(surrogate)
          self.assertEqual(memio.read(), surrogate)
  
          memio = self.ioclass()
          memio.write(surrogate)
          self.assertEqual(memio.getvalue(), surrogate)
  
  
  class PyStringIOPickleTest(TextIOTestMixin, unittest.TestCase):
      """Test if pickle restores properly the internal state of StringIO.
      """
      buftype = unicode
      UnsupportedOperation = pyio.UnsupportedOperation
      EOF = ""
  
      class ioclass(pyio.StringIO):
          def __new__(cls, *args, **kwargs):
              return pickle.loads(pickle.dumps(pyio.StringIO(*args, **kwargs)))
          def __init__(self, *args, **kwargs):
              pass
  
  
  class CBytesIOTest(PyBytesIOTest):
      ioclass = io.BytesIO
      UnsupportedOperation = io.UnsupportedOperation
  
      test_bytes_array = unittest.skip(
          "array.array() does not have the new buffer API"
      )(PyBytesIOTest.test_bytes_array)
  
  
      def test_getstate(self):
          memio = self.ioclass()
          state = memio.__getstate__()
          self.assertEqual(len(state), 3)
          bytearray(state[0]) # Check if state[0] supports the buffer interface.
          self.assertIsInstance(state[1], int)
          if state[2] is not None:
              self.assertIsInstance(state[2], dict)
          memio.close()
          self.assertRaises(ValueError, memio.__getstate__)
  
      def test_setstate(self):
          # This checks whether __setstate__ does proper input validation.
          memio = self.ioclass()
          memio.__setstate__((b"no error", 0, None))
          memio.__setstate__((bytearray(b"no error"), 0, None))
          memio.__setstate__((b"no error", 0, {'spam': 3}))
          self.assertRaises(ValueError, memio.__setstate__, (b"", -1, None))
          self.assertRaises(TypeError, memio.__setstate__, ("unicode", 0, None))
          self.assertRaises(TypeError, memio.__setstate__, (b"", 0.0, None))
          self.assertRaises(TypeError, memio.__setstate__, (b"", 0, 0))
          self.assertRaises(TypeError, memio.__setstate__, (b"len-test", 0))
          self.assertRaises(TypeError, memio.__setstate__)
          self.assertRaises(TypeError, memio.__setstate__, 0)
          memio.close()
          self.assertRaises(ValueError, memio.__setstate__, (b"closed", 0, None))
  
      check_sizeof = support.check_sizeof
  
      @support.cpython_only
      def test_sizeof(self):
          basesize = support.calcobjsize(b'P2PP2P')
          check = self.check_sizeof
          self.assertEqual(object.__sizeof__(io.BytesIO()), basesize)
          check(io.BytesIO(), basesize )
          check(io.BytesIO(b'a'), basesize + 1 + 1 )
          check(io.BytesIO(b'a' * 1000), basesize + 1000 + 1 )
  
  class CStringIOTest(PyStringIOTest):
      ioclass = io.StringIO
      UnsupportedOperation = io.UnsupportedOperation
  
      # XXX: For the Python version of io.StringIO, this is highly
      # dependent on the encoding used for the underlying buffer.
      def test_widechar(self):
          buf = self.buftype("\U0002030a\U00020347")
          memio = self.ioclass(buf)
  
          self.assertEqual(memio.getvalue(), buf)
          self.assertEqual(memio.write(buf), len(buf))
          self.assertEqual(memio.tell(), len(buf))
          self.assertEqual(memio.getvalue(), buf)
          self.assertEqual(memio.write(buf), len(buf))
          self.assertEqual(memio.tell(), len(buf) * 2)
          self.assertEqual(memio.getvalue(), buf + buf)
  
      def test_getstate(self):
          memio = self.ioclass()
          state = memio.__getstate__()
          self.assertEqual(len(state), 4)
          self.assertIsInstance(state[0], unicode)
          self.assertIsInstance(state[1], str)
          self.assertIsInstance(state[2], int)
          if state[3] is not None:
              self.assertIsInstance(state[3], dict)
          memio.close()
          self.assertRaises(ValueError, memio.__getstate__)
  
      def test_setstate(self):
          # This checks whether __setstate__ does proper input validation.
          memio = self.ioclass()
          memio.__setstate__(("no error", "\n", 0, None))
          memio.__setstate__(("no error", "", 0, {'spam': 3}))
          self.assertRaises(ValueError, memio.__setstate__, ("", "f", 0, None))
          self.assertRaises(ValueError, memio.__setstate__, ("", "", -1, None))
          self.assertRaises(TypeError, memio.__setstate__, (b"", "", 0, None))
          # trunk is more tolerant than py3k on the type of the newline param
          #self.assertRaises(TypeError, memio.__setstate__, ("", b"", 0, None))
          self.assertRaises(TypeError, memio.__setstate__, ("", "", 0.0, None))
          self.assertRaises(TypeError, memio.__setstate__, ("", "", 0, 0))
          self.assertRaises(TypeError, memio.__setstate__, ("len-test", 0))
          self.assertRaises(TypeError, memio.__setstate__)
          self.assertRaises(TypeError, memio.__setstate__, 0)
          memio.close()
          self.assertRaises(ValueError, memio.__setstate__, ("closed", "", 0, None))
  
  
  class CStringIOPickleTest(PyStringIOPickleTest):
      UnsupportedOperation = io.UnsupportedOperation
  
      class ioclass(io.StringIO):
          def __new__(cls, *args, **kwargs):
              return pickle.loads(pickle.dumps(io.StringIO(*args, **kwargs),
                                               protocol=2))
          def __init__(self, *args, **kwargs):
              pass
  
  
  def test_main():
      tests = [PyBytesIOTest, PyStringIOTest, CBytesIOTest, CStringIOTest,
               PyStringIOPickleTest, CStringIOPickleTest]
      support.run_unittest(*tests)
  
  if __name__ == '__main__':
      test_main()
  