Issue #6215: backport the 3.1 io lib

Doc/library/io.rst

@@ -573,6 +573,10 @@ Text I/O
       The name of the encoding used to decode the stream's bytes into
       strings, and to encode strings into bytes.
 
+   .. attribute:: errors
+
+      The error setting of the decoder or encoder.
+
    .. attribute:: newlines
 
       A string, a tuple of strings, or ``None``, indicating the newlines
@@ -625,13 +629,9 @@ Text I/O
    If *line_buffering* is ``True``, :meth:`flush` is implied when a call to
    write contains a newline character.
 
-   :class:`TextIOWrapper` provides these data attributes in addition to those of
+   :class:`TextIOWrapper` provides one attribute in addition to those of
    :class:`TextIOBase` and its parents:
 
-   .. attribute:: errors
-
-      The encoding and decoding error setting.
-
    .. attribute:: line_buffering
 
       Whether line buffering is enabled.

Lib/test/test_bufio.py

 import unittest
-from test import test_support
+from test import test_support as support
 
-# Simple test to ensure that optimizations in fileobject.c deliver
-# the expected results.  For best testing, run this under a debug-build
-# Python too (to exercise asserts in the C code).
+import io # C implementation.
+import _pyio as pyio # Python implementation.
 
-lengths = range(1, 257) + [512, 1000, 1024, 2048, 4096, 8192, 10000,
-                           16384, 32768, 65536, 1000000]
+# Simple test to ensure that optimizations in the IO library deliver the
+# expected results.  For best testing, run this under a debug-build Python too
+# (to exercise asserts in the C code).
+
+lengths = list(range(1, 257)) + [512, 1000, 1024, 2048, 4096, 8192, 10000,
+                                 16384, 32768, 65536, 1000000]
 
 class BufferSizeTest(unittest.TestCase):
     def try_one(self, s):
@@ -14,27 +17,27 @@ class BufferSizeTest(unittest.TestCase):
         # .readline()s deliver what we wrote.
 
         # Ensure we can open TESTFN for writing.
-        test_support.unlink(test_support.TESTFN)
+        support.unlink(support.TESTFN)
 
         # Since C doesn't guarantee we can write/read arbitrary bytes in text
         # files, use binary mode.
-        f = open(test_support.TESTFN, "wb")
+        f = self.open(support.TESTFN, "wb")
         try:
             # write once with \n and once without
             f.write(s)
-            f.write("\n")
+            f.write(b"\n")
             f.write(s)
             f.close()
-            f = open(test_support.TESTFN, "rb")
+            f = open(support.TESTFN, "rb")
             line = f.readline()
-            self.assertEqual(line, s + "\n")
+            self.assertEqual(line, s + b"\n")
             line = f.readline()
             self.assertEqual(line, s)
             line = f.readline()
             self.assert_(not line) # Must be at EOF
             f.close()
         finally:
-            test_support.unlink(test_support.TESTFN)
+            support.unlink(support.TESTFN)
 
     def drive_one(self, pattern):
         for length in lengths:
@@ -47,19 +50,27 @@ class BufferSizeTest(unittest.TestCase):
             teststring = pattern * q + pattern[:r]
             self.assertEqual(len(teststring), length)
             self.try_one(teststring)
-            self.try_one(teststring + "x")
+            self.try_one(teststring + b"x")
             self.try_one(teststring[:-1])
 
     def test_primepat(self):
         # A pattern with prime length, to avoid simple relationships with
         # stdio buffer sizes.
-        self.drive_one("1234567890\00\01\02\03\04\05\06")
+        self.drive_one(b"1234567890\00\01\02\03\04\05\06")
 
     def test_nullpat(self):
-        self.drive_one("\0" * 1000)
+        self.drive_one(bytes(1000))
+
+
+class CBufferSizeTest(BufferSizeTest):
+    open = io.open
+
+class PyBufferSizeTest(BufferSizeTest):
+    open = staticmethod(pyio.open)
+
 
 def test_main():
-    test_support.run_unittest(BufferSizeTest)
+    support.run_unittest(CBufferSizeTest, PyBufferSizeTest)
 
 if __name__ == "__main__":
     test_main()

Lib/test/test_support.py

@@ -29,7 +29,7 @@ __all__ = ["Error", "TestFailed", "ResourceDenied", "import_module",
            "run_with_locale", "set_memlimit", "bigmemtest", "bigaddrspacetest",
            "BasicTestRunner", "run_unittest", "run_doctest", "threading_setup",
            "threading_cleanup", "reap_children", "cpython_only",
-           "check_impl_detail", "get_attribute"]
+           "check_impl_detail", "get_attribute", "py3k_bytes"]
 
 class Error(Exception):
     """Base class for regression test exceptions."""
@@ -968,3 +968,18 @@ def reap_children():
                     break
             except:
                 break
+
+def py3k_bytes(b):
+    """Emulate the py3k bytes() constructor.
+
+    NOTE: This is only a best effort function.
+    """
+    try:
+        # memoryview?
+        return b.tobytes()
+    except AttributeError:
+        try:
+            # iterable of ints?
+            return b"".join(chr(x) for x in b)
+        except TypeError:
+            return bytes(b)

Misc/NEWS

@@ -317,6 +317,10 @@ Core and Builtins
 Library
 -------
 
+- Issue #6215: All bug fixes and enhancements from the Python 3.1 io library
+  (including the fast C implementation) have been backported to the standard
+  ``io`` module.
+
 - Issue #6258: Support AMD64 in bdist_msi.
 
 - Issue #5262: Fixed bug in next rollover time computation in

setup.py

@@ -438,10 +438,11 @@ class PyBuildExt(build_ext):
         exts.append( Extension("_heapq", ["_heapqmodule.c"]) )
         # operator.add() and similar goodies
         exts.append( Extension('operator', ['operator.c']) )
-        # Python 3.0 _fileio module
-        exts.append( Extension("_fileio", ["_fileio.c"]) )
-        # Python 3.0 _bytesio module
-        exts.append( Extension("_bytesio", ["_bytesio.c"]) )
+        # Python 3.1 _io library
+        exts.append( Extension("_io",
+            ["_io/bufferedio.c", "_io/bytesio.c", "_io/fileio.c",
+             "_io/iobase.c", "_io/_iomodule.c", "_io/stringio.c", "_io/textio.c"],
+             depends=["_io/_iomodule.h"], include_dirs=["Modules/_io"]))
         # _functools
         exts.append( Extension("_functools", ["_functoolsmodule.c"]) )
         # _json speedups