symbian-qemu-0.9.1-12/python-2.6.1/Lib/test/test_io.py
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Lib/test/test_io.py	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,1248 @@
+"""Unit tests for io.py."""
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import os
+import sys
+import time
+import array
+import threading
+import random
+import unittest
+from itertools import chain, cycle
+from test import test_support
+
+import codecs
+import io  # The module under test
+
+
+class MockRawIO(io.RawIOBase):
+
+    def __init__(self, read_stack=()):
+        self._read_stack = list(read_stack)
+        self._write_stack = []
+
+    def read(self, n=None):
+        try:
+            return self._read_stack.pop(0)
+        except:
+            return b""
+
+    def write(self, b):
+        self._write_stack.append(b[:])
+        return len(b)
+
+    def writable(self):
+        return True
+
+    def fileno(self):
+        return 42
+
+    def readable(self):
+        return True
+
+    def seekable(self):
+        return True
+
+    def seek(self, pos, whence):
+        pass
+
+    def tell(self):
+        return 42
+
+
+class MockFileIO(io.BytesIO):
+
+    def __init__(self, data):
+        self.read_history = []
+        io.BytesIO.__init__(self, data)
+
+    def read(self, n=None):
+        res = io.BytesIO.read(self, n)
+        self.read_history.append(None if res is None else len(res))
+        return res
+
+
+class MockNonBlockWriterIO(io.RawIOBase):
+
+    def __init__(self, blocking_script):
+        self._blocking_script = list(blocking_script)
+        self._write_stack = []
+
+    def write(self, b):
+        self._write_stack.append(b[:])
+        n = self._blocking_script.pop(0)
+        if (n < 0):
+            raise io.BlockingIOError(0, "test blocking", -n)
+        else:
+            return n
+
+    def writable(self):
+        return True
+
+
+class IOTest(unittest.TestCase):
+
+    def tearDown(self):
+        test_support.unlink(test_support.TESTFN)
+
+    def write_ops(self, f):
+        self.assertEqual(f.write(b"blah."), 5)
+        self.assertEqual(f.seek(0), 0)
+        self.assertEqual(f.write(b"Hello."), 6)
+        self.assertEqual(f.tell(), 6)
+        self.assertEqual(f.seek(-1, 1), 5)
+        self.assertEqual(f.tell(), 5)
+        self.assertEqual(f.write(bytearray(b" world\n\n\n")), 9)
+        self.assertEqual(f.seek(0), 0)
+        self.assertEqual(f.write(b"h"), 1)
+        self.assertEqual(f.seek(-1, 2), 13)
+        self.assertEqual(f.tell(), 13)
+        self.assertEqual(f.truncate(12), 12)
+        self.assertEqual(f.tell(), 12)
+        self.assertRaises(TypeError, f.seek, 0.0)
+
+    def read_ops(self, f, buffered=False):
+        data = f.read(5)
+        self.assertEqual(data, b"hello")
+        data = bytearray(data)
+        self.assertEqual(f.readinto(data), 5)
+        self.assertEqual(data, b" worl")
+        self.assertEqual(f.readinto(data), 2)
+        self.assertEqual(len(data), 5)
+        self.assertEqual(data[:2], b"d\n")
+        self.assertEqual(f.seek(0), 0)
+        self.assertEqual(f.read(20), b"hello world\n")
+        self.assertEqual(f.read(1), b"")
+        self.assertEqual(f.readinto(bytearray(b"x")), 0)
+        self.assertEqual(f.seek(-6, 2), 6)
+        self.assertEqual(f.read(5), b"world")
+        self.assertEqual(f.read(0), b"")
+        self.assertEqual(f.readinto(bytearray()), 0)
+        self.assertEqual(f.seek(-6, 1), 5)
+        self.assertEqual(f.read(5), b" worl")
+        self.assertEqual(f.tell(), 10)
+        self.assertRaises(TypeError, f.seek, 0.0)
+        if buffered:
+            f.seek(0)
+            self.assertEqual(f.read(), b"hello world\n")
+            f.seek(6)
+            self.assertEqual(f.read(), b"world\n")
+            self.assertEqual(f.read(), b"")
+
+    LARGE = 2**31
+
+    def large_file_ops(self, f):
+        assert f.readable()
+        assert f.writable()
+        self.assertEqual(f.seek(self.LARGE), self.LARGE)
+        self.assertEqual(f.tell(), self.LARGE)
+        self.assertEqual(f.write(b"xxx"), 3)
+        self.assertEqual(f.tell(), self.LARGE + 3)
+        self.assertEqual(f.seek(-1, 1), self.LARGE + 2)
+        self.assertEqual(f.truncate(), self.LARGE + 2)
+        self.assertEqual(f.tell(), self.LARGE + 2)
+        self.assertEqual(f.seek(0, 2), self.LARGE + 2)
+        self.assertEqual(f.truncate(self.LARGE + 1), self.LARGE + 1)
+        self.assertEqual(f.tell(), self.LARGE + 1)
+        self.assertEqual(f.seek(0, 2), self.LARGE + 1)
+        self.assertEqual(f.seek(-1, 2), self.LARGE)
+        self.assertEqual(f.read(2), b"x")
+
+    def test_raw_file_io(self):
+        f = io.open(test_support.TESTFN, "wb", buffering=0)
+        self.assertEqual(f.readable(), False)
+        self.assertEqual(f.writable(), True)
+        self.assertEqual(f.seekable(), True)
+        self.write_ops(f)
+        f.close()
+        f = io.open(test_support.TESTFN, "rb", buffering=0)
+        self.assertEqual(f.readable(), True)
+        self.assertEqual(f.writable(), False)
+        self.assertEqual(f.seekable(), True)
+        self.read_ops(f)
+        f.close()
+
+    def test_buffered_file_io(self):
+        f = io.open(test_support.TESTFN, "wb")
+        self.assertEqual(f.readable(), False)
+        self.assertEqual(f.writable(), True)
+        self.assertEqual(f.seekable(), True)
+        self.write_ops(f)
+        f.close()
+        f = io.open(test_support.TESTFN, "rb")
+        self.assertEqual(f.readable(), True)
+        self.assertEqual(f.writable(), False)
+        self.assertEqual(f.seekable(), True)
+        self.read_ops(f, True)
+        f.close()
+
+    def test_readline(self):
+        f = io.open(test_support.TESTFN, "wb")
+        f.write(b"abc\ndef\nxyzzy\nfoo")
+        f.close()
+        f = io.open(test_support.TESTFN, "rb")
+        self.assertEqual(f.readline(), b"abc\n")
+        self.assertEqual(f.readline(10), b"def\n")
+        self.assertEqual(f.readline(2), b"xy")
+        self.assertEqual(f.readline(4), b"zzy\n")
+        self.assertEqual(f.readline(), b"foo")
+        f.close()
+
+    def test_raw_bytes_io(self):
+        f = io.BytesIO()
+        self.write_ops(f)
+        data = f.getvalue()
+        self.assertEqual(data, b"hello world\n")
+        f = io.BytesIO(data)
+        self.read_ops(f, True)
+
+    def test_large_file_ops(self):
+        # On Windows and Mac OSX this test comsumes large resources; It takes
+        # a long time to build the >2GB file and takes >2GB of disk space
+        # therefore the resource must be enabled to run this test.
+        if sys.platform[:3] in ('win', 'os2') or sys.platform == 'darwin':
+            if not test_support.is_resource_enabled("largefile"):
+                print("\nTesting large file ops skipped on %s." % sys.platform,
+                      file=sys.stderr)
+                print("It requires %d bytes and a long time." % self.LARGE,
+                      file=sys.stderr)
+                print("Use 'regrtest.py -u largefile test_io' to run it.",
+                      file=sys.stderr)
+                return
+        f = io.open(test_support.TESTFN, "w+b", 0)
+        self.large_file_ops(f)
+        f.close()
+        f = io.open(test_support.TESTFN, "w+b")
+        self.large_file_ops(f)
+        f.close()
+
+    def test_with_open(self):
+        for bufsize in (0, 1, 100):
+            f = None
+            with open(test_support.TESTFN, "wb", bufsize) as f:
+                f.write(b"xxx")
+            self.assertEqual(f.closed, True)
+            f = None
+            try:
+                with open(test_support.TESTFN, "wb", bufsize) as f:
+                    1/0
+            except ZeroDivisionError:
+                self.assertEqual(f.closed, True)
+            else:
+                self.fail("1/0 didn't raise an exception")
+
+    def test_destructor(self):
+        record = []
+        class MyFileIO(io.FileIO):
+            def __del__(self):
+                record.append(1)
+                io.FileIO.__del__(self)
+            def close(self):
+                record.append(2)
+                io.FileIO.close(self)
+            def flush(self):
+                record.append(3)
+                io.FileIO.flush(self)
+        f = MyFileIO(test_support.TESTFN, "w")
+        f.write("xxx")
+        del f
+        self.assertEqual(record, [1, 2, 3])
+
+    def test_close_flushes(self):
+        f = io.open(test_support.TESTFN, "wb")
+        f.write(b"xxx")
+        f.close()
+        f = io.open(test_support.TESTFN, "rb")
+        self.assertEqual(f.read(), b"xxx")
+        f.close()
+
+    def XXXtest_array_writes(self):
+        # XXX memory view not available yet
+        a = array.array('i', range(10))
+        n = len(memoryview(a))
+        f = io.open(test_support.TESTFN, "wb", 0)
+        self.assertEqual(f.write(a), n)
+        f.close()
+        f = io.open(test_support.TESTFN, "wb")
+        self.assertEqual(f.write(a), n)
+        f.close()
+
+    def test_closefd(self):
+        self.assertRaises(ValueError, io.open, test_support.TESTFN, 'w',
+                          closefd=False)
+
+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.assertEquals(buf[:1], bytesIo.read(1))
+        self.assertEquals(buf[1:5], bytesIo.read(4))
+        self.assertEquals(buf[5:], bytesIo.read(900))
+        self.assertEquals(self.EOF, bytesIo.read())
+
+    def testReadNoArgs(self):
+        buf = self.buftype("1234567890")
+        bytesIo = self.ioclass(buf)
+
+        self.assertEquals(buf, bytesIo.read())
+        self.assertEquals(self.EOF, bytesIo.read())
+
+    def testSeek(self):
+        buf = self.buftype("1234567890")
+        bytesIo = self.ioclass(buf)
+
+        bytesIo.read(5)
+        bytesIo.seek(0)
+        self.assertEquals(buf, bytesIo.read())
+
+        bytesIo.seek(3)
+        self.assertEquals(buf[3:], bytesIo.read())
+        self.assertRaises(TypeError, bytesIo.seek, 0.0)
+
+    def testTell(self):
+        buf = self.buftype("1234567890")
+        bytesIo = self.ioclass(buf)
+
+        self.assertEquals(0, bytesIo.tell())
+        bytesIo.seek(5)
+        self.assertEquals(5, bytesIo.tell())
+        bytesIo.seek(10000)
+        self.assertEquals(10000, bytesIo.tell())
+
+
+class BytesIOTest(MemorySeekTestMixin, unittest.TestCase):
+    @staticmethod
+    def buftype(s):
+        return s.encode("utf-8")
+    ioclass = io.BytesIO
+    EOF = b""
+
+
+class StringIOTest(MemorySeekTestMixin, unittest.TestCase):
+    buftype = str
+    ioclass = io.StringIO
+    EOF = ""
+
+
+class BufferedReaderTest(unittest.TestCase):
+
+    def testRead(self):
+        rawio = MockRawIO((b"abc", b"d", b"efg"))
+        bufio = io.BufferedReader(rawio)
+
+        self.assertEquals(b"abcdef", bufio.read(6))
+
+    def testBuffering(self):
+        data = b"abcdefghi"
+        dlen = len(data)
+
+        tests = [
+            [ 100, [ 3, 1, 4, 8 ], [ dlen, 0 ] ],
+            [ 100, [ 3, 3, 3],     [ dlen ]    ],
+            [   4, [ 1, 2, 4, 2 ], [ 4, 4, 1 ] ],
+        ]
+
+        for bufsize, buf_read_sizes, raw_read_sizes in tests:
+            rawio = MockFileIO(data)
+            bufio = io.BufferedReader(rawio, buffer_size=bufsize)
+            pos = 0
+            for nbytes in buf_read_sizes:
+                self.assertEquals(bufio.read(nbytes), data[pos:pos+nbytes])
+                pos += nbytes
+            self.assertEquals(rawio.read_history, raw_read_sizes)
+
+    def testReadNonBlocking(self):
+        # Inject some None's in there to simulate EWOULDBLOCK
+        rawio = MockRawIO((b"abc", b"d", None, b"efg", None, None))
+        bufio = io.BufferedReader(rawio)
+
+        self.assertEquals(b"abcd", bufio.read(6))
+        self.assertEquals(b"e", bufio.read(1))
+        self.assertEquals(b"fg", bufio.read())
+        self.assert_(None is bufio.read())
+        self.assertEquals(b"", bufio.read())
+
+    def testReadToEof(self):
+        rawio = MockRawIO((b"abc", b"d", b"efg"))
+        bufio = io.BufferedReader(rawio)
+
+        self.assertEquals(b"abcdefg", bufio.read(9000))
+
+    def testReadNoArgs(self):
+        rawio = MockRawIO((b"abc", b"d", b"efg"))
+        bufio = io.BufferedReader(rawio)
+
+        self.assertEquals(b"abcdefg", bufio.read())
+
+    def testFileno(self):
+        rawio = MockRawIO((b"abc", b"d", b"efg"))
+        bufio = io.BufferedReader(rawio)
+
+        self.assertEquals(42, bufio.fileno())
+
+    def testFilenoNoFileno(self):
+        # XXX will we always have fileno() function? If so, kill
+        # this test. Else, write it.
+        pass
+
+    def testThreads(self):
+        try:
+            # Write out many bytes with exactly the same number of 0's,
+            # 1's... 255's. This will help us check that concurrent reading
+            # doesn't duplicate or forget contents.
+            N = 1000
+            l = range(256) * N
+            random.shuffle(l)
+            s = bytes(bytearray(l))
+            with io.open(test_support.TESTFN, "wb") as f:
+                f.write(s)
+            with io.open(test_support.TESTFN, "rb", buffering=0) as raw:
+                bufio = io.BufferedReader(raw, 8)
+                errors = []
+                results = []
+                def f():
+                    try:
+                        # Intra-buffer read then buffer-flushing read
+                        for n in cycle([1, 19]):
+                            s = bufio.read(n)
+                            if not s:
+                                break
+                            # list.append() is atomic
+                            results.append(s)
+                    except Exception as e:
+                        errors.append(e)
+                        raise
+                threads = [threading.Thread(target=f) for x in range(20)]
+                for t in threads:
+                    t.start()
+                time.sleep(0.02) # yield
+                for t in threads:
+                    t.join()
+                self.assertFalse(errors,
+                    "the following exceptions were caught: %r" % errors)
+                s = b''.join(results)
+                for i in range(256):
+                    c = bytes(bytearray([i]))
+                    self.assertEqual(s.count(c), N)
+        finally:
+            test_support.unlink(test_support.TESTFN)
+
+
+
+class BufferedWriterTest(unittest.TestCase):
+
+    def testWrite(self):
+        # Write to the buffered IO but don't overflow the buffer.
+        writer = MockRawIO()
+        bufio = io.BufferedWriter(writer, 8)
+
+        bufio.write(b"abc")
+
+        self.assertFalse(writer._write_stack)
+
+    def testWriteOverflow(self):
+        writer = MockRawIO()
+        bufio = io.BufferedWriter(writer, 8)
+
+        bufio.write(b"abc")
+        bufio.write(b"defghijkl")
+
+        self.assertEquals(b"abcdefghijkl", writer._write_stack[0])
+
+    def testWriteNonBlocking(self):
+        raw = MockNonBlockWriterIO((9, 2, 22, -6, 10, 12, 12))
+        bufio = io.BufferedWriter(raw, 8, 16)
+
+        bufio.write(b"asdf")
+        bufio.write(b"asdfa")
+        self.assertEquals(b"asdfasdfa", raw._write_stack[0])
+
+        bufio.write(b"asdfasdfasdf")
+        self.assertEquals(b"asdfasdfasdf", raw._write_stack[1])
+        bufio.write(b"asdfasdfasdf")
+        self.assertEquals(b"dfasdfasdf", raw._write_stack[2])
+        self.assertEquals(b"asdfasdfasdf", raw._write_stack[3])
+
+        bufio.write(b"asdfasdfasdf")
+
+        # XXX I don't like this test. It relies too heavily on how the
+        # algorithm actually works, which we might change. Refactor
+        # later.
+
+    def testFileno(self):
+        rawio = MockRawIO((b"abc", b"d", b"efg"))
+        bufio = io.BufferedWriter(rawio)
+
+        self.assertEquals(42, bufio.fileno())
+
+    def testFlush(self):
+        writer = MockRawIO()
+        bufio = io.BufferedWriter(writer, 8)
+
+        bufio.write(b"abc")
+        bufio.flush()
+
+        self.assertEquals(b"abc", writer._write_stack[0])
+
+    def testThreads(self):
+        # BufferedWriter should not raise exceptions or crash
+        # when called from multiple threads.
+        try:
+            # We use a real file object because it allows us to
+            # exercise situations where the GIL is released before
+            # writing the buffer to the raw streams. This is in addition
+            # to concurrency issues due to switching threads in the middle
+            # of Python code.
+            with io.open(test_support.TESTFN, "wb", buffering=0) as raw:
+                bufio = io.BufferedWriter(raw, 8)
+                errors = []
+                def f():
+                    try:
+                        # Write enough bytes to flush the buffer
+                        s = b"a" * 19
+                        for i in range(50):
+                            bufio.write(s)
+                    except Exception as e:
+                        errors.append(e)
+                        raise
+                threads = [threading.Thread(target=f) for x in range(20)]
+                for t in threads:
+                    t.start()
+                time.sleep(0.02) # yield
+                for t in threads:
+                    t.join()
+                self.assertFalse(errors,
+                    "the following exceptions were caught: %r" % errors)
+        finally:
+            test_support.unlink(test_support.TESTFN)
+
+
+class BufferedRWPairTest(unittest.TestCase):
+
+    def testRWPair(self):
+        r = MockRawIO(())
+        w = MockRawIO()
+        pair = io.BufferedRWPair(r, w)
+
+        # XXX need implementation
+
+
+class BufferedRandomTest(unittest.TestCase):
+
+    def testReadAndWrite(self):
+        raw = MockRawIO((b"asdf", b"ghjk"))
+        rw = io.BufferedRandom(raw, 8, 12)
+
+        self.assertEqual(b"as", rw.read(2))
+        rw.write(b"ddd")
+        rw.write(b"eee")
+        self.assertFalse(raw._write_stack) # Buffer writes
+        self.assertEqual(b"ghjk", rw.read()) # This read forces write flush
+        self.assertEquals(b"dddeee", raw._write_stack[0])
+
+    def testSeekAndTell(self):
+        raw = io.BytesIO(b"asdfghjkl")
+        rw = io.BufferedRandom(raw)
+
+        self.assertEquals(b"as", rw.read(2))
+        self.assertEquals(2, rw.tell())
+        rw.seek(0, 0)
+        self.assertEquals(b"asdf", rw.read(4))
+
+        rw.write(b"asdf")
+        rw.seek(0, 0)
+        self.assertEquals(b"asdfasdfl", rw.read())
+        self.assertEquals(9, rw.tell())
+        rw.seek(-4, 2)
+        self.assertEquals(5, rw.tell())
+        rw.seek(2, 1)
+        self.assertEquals(7, rw.tell())
+        self.assertEquals(b"fl", rw.read(11))
+        self.assertRaises(TypeError, rw.seek, 0.0)
+
+# To fully exercise seek/tell, the StatefulIncrementalDecoder has these
+# properties:
+#   - A single output character can correspond to many bytes of input.
+#   - The number of input bytes to complete the character can be
+#     undetermined until the last input byte is received.
+#   - The number of input bytes can vary depending on previous input.
+#   - A single input byte can correspond to many characters of output.
+#   - The number of output characters can be undetermined until the
+#     last input byte is received.
+#   - The number of output characters can vary depending on previous input.
+
+class StatefulIncrementalDecoder(codecs.IncrementalDecoder):
+    """
+    For testing seek/tell behavior with a stateful, buffering decoder.
+
+    Input is a sequence of words.  Words may be fixed-length (length set
+    by input) or variable-length (period-terminated).  In variable-length
+    mode, extra periods are ignored.  Possible words are:
+      - 'i' followed by a number sets the input length, I (maximum 99).
+        When I is set to 0, words are space-terminated.
+      - 'o' followed by a number sets the output length, O (maximum 99).
+      - Any other word is converted into a word followed by a period on
+        the output.  The output word consists of the input word truncated
+        or padded out with hyphens to make its length equal to O.  If O
+        is 0, the word is output verbatim without truncating or padding.
+    I and O are initially set to 1.  When I changes, any buffered input is
+    re-scanned according to the new I.  EOF also terminates the last word.
+    """
+
+    def __init__(self, errors='strict'):
+        codecs.IncrementalDecoder.__init__(self, errors)
+        self.reset()
+
+    def __repr__(self):
+        return '<SID %x>' % id(self)
+
+    def reset(self):
+        self.i = 1
+        self.o = 1
+        self.buffer = bytearray()
+
+    def getstate(self):
+        i, o = self.i ^ 1, self.o ^ 1 # so that flags = 0 after reset()
+        return bytes(self.buffer), i*100 + o
+
+    def setstate(self, state):
+        buffer, io = state
+        self.buffer = bytearray(buffer)
+        i, o = divmod(io, 100)
+        self.i, self.o = i ^ 1, o ^ 1
+
+    def decode(self, input, final=False):
+        output = ''
+        for b in input:
+            if self.i == 0: # variable-length, terminated with period
+                if b == '.':
+                    if self.buffer:
+                        output += self.process_word()
+                else:
+                    self.buffer.append(b)
+            else: # fixed-length, terminate after self.i bytes
+                self.buffer.append(b)
+                if len(self.buffer) == self.i:
+                    output += self.process_word()
+        if final and self.buffer: # EOF terminates the last word
+            output += self.process_word()
+        return output
+
+    def process_word(self):
+        output = ''
+        if self.buffer[0] == ord('i'):
+            self.i = min(99, int(self.buffer[1:] or 0)) # set input length
+        elif self.buffer[0] == ord('o'):
+            self.o = min(99, int(self.buffer[1:] or 0)) # set output length
+        else:
+            output = self.buffer.decode('ascii')
+            if len(output) < self.o:
+                output += '-'*self.o # pad out with hyphens
+            if self.o:
+                output = output[:self.o] # truncate to output length
+            output += '.'
+        self.buffer = bytearray()
+        return output
+
+    codecEnabled = False
+
+    @classmethod
+    def lookupTestDecoder(cls, name):
+        if cls.codecEnabled and name == 'test_decoder':
+            return codecs.CodecInfo(
+                name='test_decoder', encode=None, decode=None,
+                incrementalencoder=None,
+                streamreader=None, streamwriter=None,
+                incrementaldecoder=cls)
+
+# Register the previous decoder for testing.
+# Disabled by default, tests will enable it.
+codecs.register(StatefulIncrementalDecoder.lookupTestDecoder)
+
+
+class StatefulIncrementalDecoderTest(unittest.TestCase):
+    """
+    Make sure the StatefulIncrementalDecoder actually works.
+    """
+
+    test_cases = [
+        # I=1, O=1 (fixed-length input == fixed-length output)
+        (b'abcd', False, 'a.b.c.d.'),
+        # I=0, O=0 (variable-length input, variable-length output)
+        (b'oiabcd', True, 'abcd.'),
+        # I=0, O=0 (should ignore extra periods)
+        (b'oi...abcd...', True, 'abcd.'),
+        # I=0, O=6 (variable-length input, fixed-length output)
+        (b'i.o6.x.xyz.toolongtofit.', False, 'x-----.xyz---.toolon.'),
+        # I=2, O=6 (fixed-length input < fixed-length output)
+        (b'i.i2.o6xyz', True, 'xy----.z-----.'),
+        # I=6, O=3 (fixed-length input > fixed-length output)
+        (b'i.o3.i6.abcdefghijklmnop', True, 'abc.ghi.mno.'),
+        # I=0, then 3; O=29, then 15 (with longer output)
+        (b'i.o29.a.b.cde.o15.abcdefghijabcdefghij.i3.a.b.c.d.ei00k.l.m', True,
+         'a----------------------------.' +
+         'b----------------------------.' +
+         'cde--------------------------.' +
+         'abcdefghijabcde.' +
+         'a.b------------.' +
+         '.c.------------.' +
+         'd.e------------.' +
+         'k--------------.' +
+         'l--------------.' +
+         'm--------------.')
+    ]
+
+    def testDecoder(self):
+        # Try a few one-shot test cases.
+        for input, eof, output in self.test_cases:
+            d = StatefulIncrementalDecoder()
+            self.assertEquals(d.decode(input, eof), output)
+
+        # Also test an unfinished decode, followed by forcing EOF.
+        d = StatefulIncrementalDecoder()
+        self.assertEquals(d.decode(b'oiabcd'), '')
+        self.assertEquals(d.decode(b'', 1), 'abcd.')
+
+class TextIOWrapperTest(unittest.TestCase):
+
+    def setUp(self):
+        self.testdata = b"AAA\r\nBBB\rCCC\r\nDDD\nEEE\r\n"
+        self.normalized = b"AAA\nBBB\nCCC\nDDD\nEEE\n".decode("ascii")
+
+    def tearDown(self):
+        test_support.unlink(test_support.TESTFN)
+
+    def testLineBuffering(self):
+        r = io.BytesIO()
+        b = io.BufferedWriter(r, 1000)
+        t = io.TextIOWrapper(b, newline="\n", line_buffering=True)
+        t.write(u"X")
+        self.assertEquals(r.getvalue(), b"")  # No flush happened
+        t.write(u"Y\nZ")
+        self.assertEquals(r.getvalue(), b"XY\nZ")  # All got flushed
+        t.write(u"A\rB")
+        self.assertEquals(r.getvalue(), b"XY\nZA\rB")
+
+    def testEncodingErrorsReading(self):
+        # (1) default
+        b = io.BytesIO(b"abc\n\xff\n")
+        t = io.TextIOWrapper(b, encoding="ascii")
+        self.assertRaises(UnicodeError, t.read)
+        # (2) explicit strict
+        b = io.BytesIO(b"abc\n\xff\n")
+        t = io.TextIOWrapper(b, encoding="ascii", errors="strict")
+        self.assertRaises(UnicodeError, t.read)
+        # (3) ignore
+        b = io.BytesIO(b"abc\n\xff\n")
+        t = io.TextIOWrapper(b, encoding="ascii", errors="ignore")
+        self.assertEquals(t.read(), "abc\n\n")
+        # (4) replace
+        b = io.BytesIO(b"abc\n\xff\n")
+        t = io.TextIOWrapper(b, encoding="ascii", errors="replace")
+        self.assertEquals(t.read(), u"abc\n\ufffd\n")
+
+    def testEncodingErrorsWriting(self):
+        # (1) default
+        b = io.BytesIO()
+        t = io.TextIOWrapper(b, encoding="ascii")
+        self.assertRaises(UnicodeError, t.write, u"\xff")
+        # (2) explicit strict
+        b = io.BytesIO()
+        t = io.TextIOWrapper(b, encoding="ascii", errors="strict")
+        self.assertRaises(UnicodeError, t.write, u"\xff")
+        # (3) ignore
+        b = io.BytesIO()
+        t = io.TextIOWrapper(b, encoding="ascii", errors="ignore",
+                             newline="\n")
+        t.write(u"abc\xffdef\n")
+        t.flush()
+        self.assertEquals(b.getvalue(), b"abcdef\n")
+        # (4) replace
+        b = io.BytesIO()
+        t = io.TextIOWrapper(b, encoding="ascii", errors="replace",
+                             newline="\n")
+        t.write(u"abc\xffdef\n")
+        t.flush()
+        self.assertEquals(b.getvalue(), b"abc?def\n")
+
+    def testNewlinesInput(self):
+        testdata = b"AAA\nBBB\nCCC\rDDD\rEEE\r\nFFF\r\nGGG"
+        normalized = testdata.replace(b"\r\n", b"\n").replace(b"\r", b"\n")
+        for newline, expected in [
+            (None, normalized.decode("ascii").splitlines(True)),
+            ("", testdata.decode("ascii").splitlines(True)),
+            ("\n", ["AAA\n", "BBB\n", "CCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
+            ("\r\n", ["AAA\nBBB\nCCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
+            ("\r",  ["AAA\nBBB\nCCC\r", "DDD\r", "EEE\r", "\nFFF\r", "\nGGG"]),
+            ]:
+            buf = io.BytesIO(testdata)
+            txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
+            self.assertEquals(txt.readlines(), expected)
+            txt.seek(0)
+            self.assertEquals(txt.read(), "".join(expected))
+
+    def testNewlinesOutput(self):
+        testdict = {
+            "": b"AAA\nBBB\nCCC\nX\rY\r\nZ",
+            "\n": b"AAA\nBBB\nCCC\nX\rY\r\nZ",
+            "\r": b"AAA\rBBB\rCCC\rX\rY\r\rZ",
+            "\r\n": b"AAA\r\nBBB\r\nCCC\r\nX\rY\r\r\nZ",
+            }
+        tests = [(None, testdict[os.linesep])] + sorted(testdict.items())
+        for newline, expected in tests:
+            buf = io.BytesIO()
+            txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
+            txt.write("AAA\nB")
+            txt.write("BB\nCCC\n")
+            txt.write("X\rY\r\nZ")
+            txt.flush()
+            self.assertEquals(buf.closed, False)
+            self.assertEquals(buf.getvalue(), expected)
+
+    def testNewlines(self):
+        input_lines = [ "unix\n", "windows\r\n", "os9\r", "last\n", "nonl" ]
+
+        tests = [
+            [ None, [ 'unix\n', 'windows\n', 'os9\n', 'last\n', 'nonl' ] ],
+            [ '', input_lines ],
+            [ '\n', [ "unix\n", "windows\r\n", "os9\rlast\n", "nonl" ] ],
+            [ '\r\n', [ "unix\nwindows\r\n", "os9\rlast\nnonl" ] ],
+            [ '\r', [ "unix\nwindows\r", "\nos9\r", "last\nnonl" ] ],
+        ]
+
+        encodings = ('utf-8', 'latin-1')
+
+        # Try a range of buffer sizes to test the case where \r is the last
+        # character in TextIOWrapper._pending_line.
+        for encoding in encodings:
+            # XXX: str.encode() should return bytes
+            data = bytes(''.join(input_lines).encode(encoding))
+            for do_reads in (False, True):
+                for bufsize in range(1, 10):
+                    for newline, exp_lines in tests:
+                        bufio = io.BufferedReader(io.BytesIO(data), bufsize)
+                        textio = io.TextIOWrapper(bufio, newline=newline,
+                                                  encoding=encoding)
+                        if do_reads:
+                            got_lines = []
+                            while True:
+                                c2 = textio.read(2)
+                                if c2 == '':
+                                    break
+                                self.assertEquals(len(c2), 2)
+                                got_lines.append(c2 + textio.readline())
+                        else:
+                            got_lines = list(textio)
+
+                        for got_line, exp_line in zip(got_lines, exp_lines):
+                            self.assertEquals(got_line, exp_line)
+                        self.assertEquals(len(got_lines), len(exp_lines))
+
+    def testNewlinesInput(self):
+        testdata = b"AAA\nBBB\nCCC\rDDD\rEEE\r\nFFF\r\nGGG"
+        normalized = testdata.replace(b"\r\n", b"\n").replace(b"\r", b"\n")
+        for newline, expected in [
+            (None, normalized.decode("ascii").splitlines(True)),
+            ("", testdata.decode("ascii").splitlines(True)),
+            ("\n", ["AAA\n", "BBB\n", "CCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
+            ("\r\n", ["AAA\nBBB\nCCC\rDDD\rEEE\r\n", "FFF\r\n", "GGG"]),
+            ("\r",  ["AAA\nBBB\nCCC\r", "DDD\r", "EEE\r", "\nFFF\r", "\nGGG"]),
+            ]:
+            buf = io.BytesIO(testdata)
+            txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
+            self.assertEquals(txt.readlines(), expected)
+            txt.seek(0)
+            self.assertEquals(txt.read(), "".join(expected))
+
+    def testNewlinesOutput(self):
+        data = u"AAA\nBBB\rCCC\n"
+        data_lf = b"AAA\nBBB\rCCC\n"
+        data_cr = b"AAA\rBBB\rCCC\r"
+        data_crlf = b"AAA\r\nBBB\rCCC\r\n"
+        save_linesep = os.linesep
+        try:
+            for os.linesep, newline, expected in [
+                ("\n", None, data_lf),
+                ("\r\n", None, data_crlf),
+                ("\n", "", data_lf),
+                ("\r\n", "", data_lf),
+                ("\n", "\n", data_lf),
+                ("\r\n", "\n", data_lf),
+                ("\n", "\r", data_cr),
+                ("\r\n", "\r", data_cr),
+                ("\n", "\r\n", data_crlf),
+                ("\r\n", "\r\n", data_crlf),
+                ]:
+                buf = io.BytesIO()
+                txt = io.TextIOWrapper(buf, encoding="ascii", newline=newline)
+                txt.write(data)
+                txt.close()
+                self.assertEquals(buf.closed, True)
+                self.assertRaises(ValueError, buf.getvalue)
+        finally:
+            os.linesep = save_linesep
+
+    # Systematic tests of the text I/O API
+
+    def testBasicIO(self):
+        for chunksize in (1, 2, 3, 4, 5, 15, 16, 17, 31, 32, 33, 63, 64, 65):
+            for enc in "ascii", "latin1", "utf8" :# , "utf-16-be", "utf-16-le":
+                f = io.open(test_support.TESTFN, "w+", encoding=enc)
+                f._CHUNK_SIZE = chunksize
+                self.assertEquals(f.write(u"abc"), 3)
+                f.close()
+                f = io.open(test_support.TESTFN, "r+", encoding=enc)
+                f._CHUNK_SIZE = chunksize
+                self.assertEquals(f.tell(), 0)
+                self.assertEquals(f.read(), u"abc")
+                cookie = f.tell()
+                self.assertEquals(f.seek(0), 0)
+                self.assertEquals(f.read(2), u"ab")
+                self.assertEquals(f.read(1), u"c")
+                self.assertEquals(f.read(1), u"")
+                self.assertEquals(f.read(), u"")
+                self.assertEquals(f.tell(), cookie)
+                self.assertEquals(f.seek(0), 0)
+                self.assertEquals(f.seek(0, 2), cookie)
+                self.assertEquals(f.write(u"def"), 3)
+                self.assertEquals(f.seek(cookie), cookie)
+                self.assertEquals(f.read(), u"def")
+                if enc.startswith("utf"):
+                    self.multi_line_test(f, enc)
+                f.close()
+
+    def multi_line_test(self, f, enc):
+        f.seek(0)
+        f.truncate()
+        sample = u"s\xff\u0fff\uffff"
+        wlines = []
+        for size in (0, 1, 2, 3, 4, 5, 30, 31, 32, 33, 62, 63, 64, 65, 1000):
+            chars = []
+            for i in range(size):
+                chars.append(sample[i % len(sample)])
+            line = u"".join(chars) + u"\n"
+            wlines.append((f.tell(), line))
+            f.write(line)
+        f.seek(0)
+        rlines = []
+        while True:
+            pos = f.tell()
+            line = f.readline()
+            if not line:
+                break
+            rlines.append((pos, line))
+        self.assertEquals(rlines, wlines)
+
+    def testTelling(self):
+        f = io.open(test_support.TESTFN, "w+", encoding="utf8")
+        p0 = f.tell()
+        f.write(u"\xff\n")
+        p1 = f.tell()
+        f.write(u"\xff\n")
+        p2 = f.tell()
+        f.seek(0)
+        self.assertEquals(f.tell(), p0)
+        self.assertEquals(f.readline(), u"\xff\n")
+        self.assertEquals(f.tell(), p1)
+        self.assertEquals(f.readline(), u"\xff\n")
+        self.assertEquals(f.tell(), p2)
+        f.seek(0)
+        for line in f:
+            self.assertEquals(line, u"\xff\n")
+            self.assertRaises(IOError, f.tell)
+        self.assertEquals(f.tell(), p2)
+        f.close()
+
+    def testSeeking(self):
+        chunk_size = io.TextIOWrapper._CHUNK_SIZE
+        prefix_size = chunk_size - 2
+        u_prefix = "a" * prefix_size
+        prefix = bytes(u_prefix.encode("utf-8"))
+        self.assertEquals(len(u_prefix), len(prefix))
+        u_suffix = "\u8888\n"
+        suffix = bytes(u_suffix.encode("utf-8"))
+        line = prefix + suffix
+        f = io.open(test_support.TESTFN, "wb")
+        f.write(line*2)
+        f.close()
+        f = io.open(test_support.TESTFN, "r", encoding="utf-8")
+        s = f.read(prefix_size)
+        self.assertEquals(s, unicode(prefix, "ascii"))
+        self.assertEquals(f.tell(), prefix_size)
+        self.assertEquals(f.readline(), u_suffix)
+
+    def testSeekingToo(self):
+        # Regression test for a specific bug
+        data = b'\xe0\xbf\xbf\n'
+        f = io.open(test_support.TESTFN, "wb")
+        f.write(data)
+        f.close()
+        f = io.open(test_support.TESTFN, "r", encoding="utf-8")
+        f._CHUNK_SIZE  # Just test that it exists
+        f._CHUNK_SIZE = 2
+        f.readline()
+        f.tell()
+
+    def testSeekAndTell(self):
+        """Test seek/tell using the StatefulIncrementalDecoder."""
+
+        def testSeekAndTellWithData(data, min_pos=0):
+            """Tell/seek to various points within a data stream and ensure
+            that the decoded data returned by read() is consistent."""
+            f = io.open(test_support.TESTFN, 'wb')
+            f.write(data)
+            f.close()
+            f = io.open(test_support.TESTFN, encoding='test_decoder')
+            decoded = f.read()
+            f.close()
+
+            for i in range(min_pos, len(decoded) + 1): # seek positions
+                for j in [1, 5, len(decoded) - i]: # read lengths
+                    f = io.open(test_support.TESTFN, encoding='test_decoder')
+                    self.assertEquals(f.read(i), decoded[:i])
+                    cookie = f.tell()
+                    self.assertEquals(f.read(j), decoded[i:i + j])
+                    f.seek(cookie)
+                    self.assertEquals(f.read(), decoded[i:])
+                    f.close()
+
+        # Enable the test decoder.
+        StatefulIncrementalDecoder.codecEnabled = 1
+
+        # Run the tests.
+        try:
+            # Try each test case.
+            for input, _, _ in StatefulIncrementalDecoderTest.test_cases:
+                testSeekAndTellWithData(input)
+
+            # Position each test case so that it crosses a chunk boundary.
+            CHUNK_SIZE = io.TextIOWrapper._CHUNK_SIZE
+            for input, _, _ in StatefulIncrementalDecoderTest.test_cases:
+                offset = CHUNK_SIZE - len(input)//2
+                prefix = b'.'*offset
+                # Don't bother seeking into the prefix (takes too long).
+                min_pos = offset*2
+                testSeekAndTellWithData(prefix + input, min_pos)
+
+        # Ensure our test decoder won't interfere with subsequent tests.
+        finally:
+            StatefulIncrementalDecoder.codecEnabled = 0
+
+    def testEncodedWrites(self):
+        data = u"1234567890"
+        tests = ("utf-16",
+                 "utf-16-le",
+                 "utf-16-be",
+                 "utf-32",
+                 "utf-32-le",
+                 "utf-32-be")
+        for encoding in tests:
+            buf = io.BytesIO()
+            f = io.TextIOWrapper(buf, encoding=encoding)
+            # Check if the BOM is written only once (see issue1753).
+            f.write(data)
+            f.write(data)
+            f.seek(0)
+            self.assertEquals(f.read(), data * 2)
+            self.assertEquals(buf.getvalue(), (data * 2).encode(encoding))
+
+    def timingTest(self):
+        timer = time.time
+        enc = "utf8"
+        line = "\0\x0f\xff\u0fff\uffff\U000fffff\U0010ffff"*3 + "\n"
+        nlines = 10000
+        nchars = len(line)
+        nbytes = len(line.encode(enc))
+        for chunk_size in (32, 64, 128, 256):
+            f = io.open(test_support.TESTFN, "w+", encoding=enc)
+            f._CHUNK_SIZE = chunk_size
+            t0 = timer()
+            for i in range(nlines):
+                f.write(line)
+            f.flush()
+            t1 = timer()
+            f.seek(0)
+            for line in f:
+                pass
+            t2 = timer()
+            f.seek(0)
+            while f.readline():
+                pass
+            t3 = timer()
+            f.seek(0)
+            while f.readline():
+                f.tell()
+            t4 = timer()
+            f.close()
+            if test_support.verbose:
+                print("\nTiming test: %d lines of %d characters (%d bytes)" %
+                      (nlines, nchars, nbytes))
+                print("File chunk size:          %6s" % f._CHUNK_SIZE)
+                print("Writing:                  %6.3f seconds" % (t1-t0))
+                print("Reading using iteration:  %6.3f seconds" % (t2-t1))
+                print("Reading using readline(): %6.3f seconds" % (t3-t2))
+                print("Using readline()+tell():  %6.3f seconds" % (t4-t3))
+
+    def testReadOneByOne(self):
+        txt = io.TextIOWrapper(io.BytesIO(b"AA\r\nBB"))
+        reads = ""
+        while True:
+            c = txt.read(1)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, "AA\nBB")
+
+    # read in amounts equal to TextIOWrapper._CHUNK_SIZE which is 128.
+    def testReadByChunk(self):
+        # make sure "\r\n" straddles 128 char boundary.
+        txt = io.TextIOWrapper(io.BytesIO(b"A" * 127 + b"\r\nB"))
+        reads = ""
+        while True:
+            c = txt.read(128)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, "A"*127+"\nB")
+
+    def test_issue1395_1(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+
+        # read one char at a time
+        reads = ""
+        while True:
+            c = txt.read(1)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_2(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = ""
+        while True:
+            c = txt.read(4)
+            if not c:
+                break
+            reads += c
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_3(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = txt.read(4)
+        reads += txt.read(4)
+        reads += txt.readline()
+        reads += txt.readline()
+        reads += txt.readline()
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_4(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = txt.read(4)
+        reads += txt.read()
+        self.assertEquals(reads, self.normalized)
+
+    def test_issue1395_5(self):
+        txt = io.TextIOWrapper(io.BytesIO(self.testdata), encoding="ascii")
+        txt._CHUNK_SIZE = 4
+
+        reads = txt.read(4)
+        pos = txt.tell()
+        txt.seek(0)
+        txt.seek(pos)
+        self.assertEquals(txt.read(4), "BBB\n")
+
+    def test_issue2282(self):
+        buffer = io.BytesIO(self.testdata)
+        txt = io.TextIOWrapper(buffer, encoding="ascii")
+
+        self.assertEqual(buffer.seekable(), txt.seekable())
+
+    def test_newline_decoder(self):
+        import codecs
+        decoder = codecs.getincrementaldecoder("utf-8")()
+        decoder = io.IncrementalNewlineDecoder(decoder, translate=True)
+
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88'), u"\u8888")
+
+        self.assertEquals(decoder.decode(b'\xe8'), u"")
+        self.assertEquals(decoder.decode(b'\xa2'), u"")
+        self.assertEquals(decoder.decode(b'\x88'), u"\u8888")
+
+        self.assertEquals(decoder.decode(b'\xe8'), u"")
+        self.assertRaises(UnicodeDecodeError, decoder.decode, b'', final=True)
+
+        decoder.setstate((b'', 0))
+        self.assertEquals(decoder.decode(b'\n'), u"\n")
+        self.assertEquals(decoder.decode(b'\r'), u"")
+        self.assertEquals(decoder.decode(b'', final=True), u"\n")
+        self.assertEquals(decoder.decode(b'\r', final=True), u"\n")
+
+        self.assertEquals(decoder.decode(b'\r'), u"")
+        self.assertEquals(decoder.decode(b'a'), u"\na")
+
+        self.assertEquals(decoder.decode(b'\r\r\n'), u"\n\n")
+        self.assertEquals(decoder.decode(b'\r'), u"")
+        self.assertEquals(decoder.decode(b'\r'), u"\n")
+        self.assertEquals(decoder.decode(b'\na'), u"\na")
+
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88\r\n'), u"\u8888\n")
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88'), u"\u8888")
+        self.assertEquals(decoder.decode(b'\n'), u"\n")
+        self.assertEquals(decoder.decode(b'\xe8\xa2\x88\r'), u"\u8888")
+        self.assertEquals(decoder.decode(b'\n'), u"\n")
+
+        decoder = codecs.getincrementaldecoder("utf-8")()
+        decoder = io.IncrementalNewlineDecoder(decoder, translate=True)
+        self.assertEquals(decoder.newlines, None)
+        decoder.decode(b"abc\n\r")
+        self.assertEquals(decoder.newlines, u'\n')
+        decoder.decode(b"\nabc")
+        self.assertEquals(decoder.newlines, ('\n', '\r\n'))
+        decoder.decode(b"abc\r")
+        self.assertEquals(decoder.newlines, ('\n', '\r\n'))
+        decoder.decode(b"abc")
+        self.assertEquals(decoder.newlines, ('\r', '\n', '\r\n'))
+        decoder.decode(b"abc\r")
+        decoder.reset()
+        self.assertEquals(decoder.decode(b"abc"), "abc")
+        self.assertEquals(decoder.newlines, None)
+
+# XXX Tests for open()
+
+class MiscIOTest(unittest.TestCase):
+
+    def testImport__all__(self):
+        for name in io.__all__:
+            obj = getattr(io, name, None)
+            self.assert_(obj is not None, name)
+            if name == "open":
+                continue
+            elif "error" in name.lower():
+                self.assert_(issubclass(obj, Exception), name)
+            else:
+                self.assert_(issubclass(obj, io.IOBase))
+
+
+def test_main():
+    test_support.run_unittest(IOTest, BytesIOTest, StringIOTest,
+                              BufferedReaderTest, BufferedWriterTest,
+                              BufferedRWPairTest, BufferedRandomTest,
+                              StatefulIncrementalDecoderTest,
+                              TextIOWrapperTest, MiscIOTest)
+
+if __name__ == "__main__":
+    unittest.main()