down integrate python opensource to svn

34 files changed, 2823 insertions, 569 deletions

diff --git a/python/google/protobuf/internal/api_implementation.cc b/python/google/protobuf/internal/api_implementation.cc
new file mode 100644
index 00000000..ad6fd9c8
--- /dev/null
+++ b/python/google/protobuf/internal/api_implementation.cc
@@ -0,0 +1,139 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <Python.h>
+
+namespace google {
+namespace protobuf {
+namespace python {
+
+// Version constant.
+// This is either 0 for python, 1 for CPP V1, 2 for CPP V2.
+//
+// 0 is default and is equivalent to
+//   PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python
+//
+// 1 is set with -DPYTHON_PROTO2_CPP_IMPL_V1 and is equivalent to
+//   PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp
+// and
+//   PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION=1
+//
+// 2 is set with -DPYTHON_PROTO2_CPP_IMPL_V2 and is equivalent to
+//   PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp
+// and
+//   PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION=2
+#ifdef PYTHON_PROTO2_CPP_IMPL_V1
+#if PY_MAJOR_VERSION >= 3
+#error "PYTHON_PROTO2_CPP_IMPL_V1 is not supported under Python 3."
+#endif
+static int kImplVersion = 1;
+#else
+#ifdef PYTHON_PROTO2_CPP_IMPL_V2
+static int kImplVersion = 2;
+#else
+#ifdef PYTHON_PROTO2_PYTHON_IMPL
+static int kImplVersion = 0;
+#else
+
+// The defaults are set here.  Python 3 uses the fast C++ APIv2 by default.
+// Python 2 still uses the Python version by default until some compatibility
+// issues can be worked around.
+#if PY_MAJOR_VERSION >= 3
+static int kImplVersion = 2;
+#else
+static int kImplVersion = 0;
+#endif
+
+#endif  // PYTHON_PROTO2_PYTHON_IMPL
+#endif  // PYTHON_PROTO2_CPP_IMPL_V2
+#endif  // PYTHON_PROTO2_CPP_IMPL_V1
+
+static const char* kImplVersionName = "api_version";
+
+static const char* kModuleName = "_api_implementation";
+static const char kModuleDocstring[] =
+"_api_implementation is a module that exposes compile-time constants that\n"
+"determine the default API implementation to use for Python proto2.\n"
+"\n"
+"It complements api_implementation.py by setting defaults using compile-time\n"
+"constants defined in C, such that one can set defaults at compilation\n"
+"(e.g. with blaze flag --copt=-DPYTHON_PROTO2_CPP_IMPL_V2).";
+
+#if PY_MAJOR_VERSION >= 3
+static struct PyModuleDef _module = {
+  PyModuleDef_HEAD_INIT,
+  kModuleName,
+  kModuleDocstring,
+  -1,
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  NULL
+};
+#define INITFUNC PyInit__api_implementation
+#define INITFUNC_ERRORVAL NULL
+#else
+#define INITFUNC init_api_implementation
+#define INITFUNC_ERRORVAL
+#endif
+
+extern "C" {
+  PyMODINIT_FUNC INITFUNC() {
+#if PY_MAJOR_VERSION >= 3
+    PyObject *module = PyModule_Create(&_module);
+#else
+    PyObject *module = Py_InitModule3(
+        const_cast<char*>(kModuleName),
+        NULL,
+        const_cast<char*>(kModuleDocstring));
+#endif
+    if (module == NULL) {
+      return INITFUNC_ERRORVAL;
+    }
+
+    // Adds the module variable "api_version".
+    if (PyModule_AddIntConstant(
+        module,
+        const_cast<char*>(kImplVersionName),
+        kImplVersion))
+#if PY_MAJOR_VERSION < 3
+      return;
+#else
+      { Py_DECREF(module); return NULL; }
+
+    return module;
+#endif
+  }
+}
+
+}  // namespace python
+}  // namespace protobuf
+}  // namespace google
diff --git a/python/google/protobuf/internal/api_implementation.py b/python/google/protobuf/internal/api_implementation.py
index ce02a329..cbb85747 100755
--- a/python/google/protobuf/internal/api_implementation.py
+++ b/python/google/protobuf/internal/api_implementation.py
@@ -28,41 +28,44 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+"""Determine which implementation of the protobuf API is used in this process.
 """
-This module is the central entity that determines which implementation of the
-API is used.
-"""
-
-__author__ = 'petar@google.com (Petar Petrov)'
 
 import os
+import sys
+
+try:
+  # pylint: disable=g-import-not-at-top
+  from google.protobuf.internal import _api_implementation
+  # The compile-time constants in the _api_implementation module can be used to
+  # switch to a certain implementation of the Python API at build time.
+  _api_version = _api_implementation.api_version
+  del _api_implementation
+except ImportError:
+  _api_version = 0
+
+_default_implementation_type = (
+    'python' if _api_version == 0 else 'cpp')
+_default_version_str = (
+    '1' if _api_version <= 1 else '2')
+
 # This environment variable can be used to switch to a certain implementation
-# of the Python API. Right now only 'python' and 'cpp' are valid values. Any
-# other value will be ignored.
+# of the Python API, overriding the compile-time constants in the
+# _api_implementation module. Right now only 'python' and 'cpp' are valid
+# values. Any other value will be ignored.
 _implementation_type = os.getenv('PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION',
-                                 'python')
-
+                                 _default_implementation_type)
 
 if _implementation_type != 'python':
-  # For now, by default use the pure-Python implementation.
-  # The code below checks if the C extension is available and
-  # uses it if it is available.
   _implementation_type = 'cpp'
-  ## Determine automatically which implementation to use.
-  #try:
-  #  from google.protobuf.internal import cpp_message
-  #  _implementation_type = 'cpp'
-  #except ImportError, e:
-  #  _implementation_type = 'python'
-
 
 # This environment variable can be used to switch between the two
-# 'cpp' implementations. Right now only 1 and 2 are valid values. Any
-# other value will be ignored.
+# 'cpp' implementations, overriding the compile-time constants in the
+# _api_implementation module. Right now only 1 and 2 are valid values. Any other
+# value will be ignored.
 _implementation_version_str = os.getenv(
     'PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION',
-    '1')
-
+    _default_version_str)
 
 if _implementation_version_str not in ('1', '2'):
   raise ValueError(
@@ -70,11 +73,9 @@ if _implementation_version_str not in ('1', '2'):
       _implementation_version_str + "' (supported versions: 1, 2)"
       )
 
-
 _implementation_version = int(_implementation_version_str)
 
 
-
 # Usage of this function is discouraged. Clients shouldn't care which
 # implementation of the API is in use. Note that there is no guarantee
 # that differences between APIs will be maintained.
@@ -82,6 +83,7 @@ _implementation_version = int(_implementation_version_str)
 def Type():
   return _implementation_type
 
+
 # See comment on 'Type' above.
 def Version():
   return _implementation_version
diff --git a/python/google/protobuf/internal/api_implementation_default_test.py b/python/google/protobuf/internal/api_implementation_default_test.py
new file mode 100644
index 00000000..b2b41284
--- /dev/null
+++ b/python/google/protobuf/internal/api_implementation_default_test.py
@@ -0,0 +1,63 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Test that the api_implementation defaults are what we expect."""
+
+import os
+import sys
+# Clear environment implementation settings before the google3 imports.
+os.environ.pop('PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION', None)
+os.environ.pop('PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION', None)
+
+# pylint: disable=g-import-not-at-top
+from google.apputils import basetest
+from google.protobuf.internal import api_implementation
+
+
+class ApiImplementationDefaultTest(basetest.TestCase):
+
+  if sys.version_info.major <= 2:
+
+    def testThatPythonIsTheDefault(self):
+      """If -DPYTHON_PROTO_*IMPL* was given at build time, this may fail."""
+      self.assertEqual('python', api_implementation.Type())
+
+  else:
+
+    def testThatCppApiV2IsTheDefault(self):
+      """If -DPYTHON_PROTO_*IMPL* was given at build time, this may fail."""
+      self.assertEqual('cpp', api_implementation.Type())
+      self.assertEqual(2, api_implementation.Version())
+
+
+if __name__ == '__main__':
+  basetest.main()
diff --git a/python/google/protobuf/internal/containers.py b/python/google/protobuf/internal/containers.py
index 34b35f8a..5797e81b 100755
--- a/python/google/protobuf/internal/containers.py
+++ b/python/google/protobuf/internal/containers.py
@@ -108,15 +108,13 @@ class RepeatedScalarFieldContainer(BaseContainer):
 
   def append(self, value):
     """Appends an item to the list. Similar to list.append()."""
-    self._type_checker.CheckValue(value)
-    self._values.append(value)
+    self._values.append(self._type_checker.CheckValue(value))
     if not self._message_listener.dirty:
       self._message_listener.Modified()
 
   def insert(self, key, value):
     """Inserts the item at the specified position. Similar to list.insert()."""
-    self._type_checker.CheckValue(value)
-    self._values.insert(key, value)
+    self._values.insert(key, self._type_checker.CheckValue(value))
     if not self._message_listener.dirty:
       self._message_listener.Modified()
 
@@ -127,8 +125,7 @@ class RepeatedScalarFieldContainer(BaseContainer):
 
     new_values = []
     for elem in elem_seq:
-      self._type_checker.CheckValue(elem)
-      new_values.append(elem)
+      new_values.append(self._type_checker.CheckValue(elem))
     self._values.extend(new_values)
     self._message_listener.Modified()
 
@@ -146,9 +143,13 @@ class RepeatedScalarFieldContainer(BaseContainer):
 
   def __setitem__(self, key, value):
     """Sets the item on the specified position."""
-    self._type_checker.CheckValue(value)
-    self._values[key] = value
-    self._message_listener.Modified()
+    if isinstance(key, slice):  # PY3
+      if key.step is not None:
+        raise ValueError('Extended slices not supported')
+      self.__setslice__(key.start, key.stop, value)
+    else:
+      self._values[key] = self._type_checker.CheckValue(value)
+      self._message_listener.Modified()
 
   def __getslice__(self, start, stop):
     """Retrieves the subset of items from between the specified indices."""
@@ -158,8 +159,7 @@ class RepeatedScalarFieldContainer(BaseContainer):
     """Sets the subset of items from between the specified indices."""
     new_values = []
     for value in values:
-      self._type_checker.CheckValue(value)
-      new_values.append(value)
+      new_values.append(self._type_checker.CheckValue(value))
     self._values[start:stop] = new_values
     self._message_listener.Modified()
 
diff --git a/python/google/protobuf/internal/cpp_message.py b/python/google/protobuf/internal/cpp_message.py
index 23ab9ba4..8eb38ca4 100755
--- a/python/google/protobuf/internal/cpp_message.py
+++ b/python/google/protobuf/internal/cpp_message.py
@@ -610,7 +610,7 @@ def _AddMessageMethods(message_descriptor, cls):
     return self._cmsg.FindInitializationErrors()
 
   def __str__(self):
-    return self._cmsg.DebugString()
+    return str(self._cmsg)
 
   def __eq__(self, other):
     if self is other:
diff --git a/python/google/protobuf/internal/decoder.py b/python/google/protobuf/internal/decoder.py
index cb6f5729..651ee0d4 100755
--- a/python/google/protobuf/internal/decoder.py
+++ b/python/google/protobuf/internal/decoder.py
@@ -28,6 +28,10 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#PY25 compatible for GAE.
+#
+# Copyright 2009 Google Inc. All Rights Reserved.
+
 """Code for decoding protocol buffer primitives.
 
 This code is very similar to encoder.py -- read the docs for that module first.
@@ -81,6 +85,8 @@ we repeatedly read a tag, look up the corresponding decoder, and invoke it.
 __author__ = 'kenton@google.com (Kenton Varda)'
 
 import struct
+import sys  ##PY25
+_PY2 = sys.version_info[0] < 3  ##PY25
 from google.protobuf.internal import encoder
 from google.protobuf.internal import wire_format
 from google.protobuf import message
@@ -98,7 +104,7 @@ _NAN = _POS_INF * 0
 _DecodeError = message.DecodeError
 
 
-def _VarintDecoder(mask):
+def _VarintDecoder(mask, result_type):
   """Return an encoder for a basic varint value (does not include tag).
 
   Decoded values will be bitwise-anded with the given mask before being
@@ -109,15 +115,18 @@ def _VarintDecoder(mask):
   """
 
   local_ord = ord
+  py2 = _PY2  ##PY25
+##!PY25  py2 = str is bytes
   def DecodeVarint(buffer, pos):
     result = 0
     shift = 0
     while 1:
-      b = local_ord(buffer[pos])
+      b = local_ord(buffer[pos]) if py2 else buffer[pos]
       result |= ((b & 0x7f) << shift)
       pos += 1
       if not (b & 0x80):
         result &= mask
+        result = result_type(result)
         return (result, pos)
       shift += 7
       if shift >= 64:
@@ -125,15 +134,17 @@ def _VarintDecoder(mask):
   return DecodeVarint
 
 
-def _SignedVarintDecoder(mask):
+def _SignedVarintDecoder(mask, result_type):
   """Like _VarintDecoder() but decodes signed values."""
 
   local_ord = ord
+  py2 = _PY2  ##PY25
+##!PY25  py2 = str is bytes
   def DecodeVarint(buffer, pos):
     result = 0
     shift = 0
     while 1:
-      b = local_ord(buffer[pos])
+      b = local_ord(buffer[pos]) if py2 else buffer[pos]
       result |= ((b & 0x7f) << shift)
       pos += 1
       if not (b & 0x80):
@@ -142,19 +153,23 @@ def _SignedVarintDecoder(mask):
           result |= ~mask
         else:
           result &= mask
+        result = result_type(result)
         return (result, pos)
       shift += 7
       if shift >= 64:
         raise _DecodeError('Too many bytes when decoding varint.')
   return DecodeVarint
 
+# We force 32-bit values to int and 64-bit values to long to make
+# alternate implementations where the distinction is more significant
+# (e.g. the C++ implementation) simpler.
 
-_DecodeVarint = _VarintDecoder((1 << 64) - 1)
-_DecodeSignedVarint = _SignedVarintDecoder((1 << 64) - 1)
+_DecodeVarint = _VarintDecoder((1 << 64) - 1, long)
+_DecodeSignedVarint = _SignedVarintDecoder((1 << 64) - 1, long)
 
 # Use these versions for values which must be limited to 32 bits.
-_DecodeVarint32 = _VarintDecoder((1 << 32) - 1)
-_DecodeSignedVarint32 = _SignedVarintDecoder((1 << 32) - 1)
+_DecodeVarint32 = _VarintDecoder((1 << 32) - 1, int)
+_DecodeSignedVarint32 = _SignedVarintDecoder((1 << 32) - 1, int)
 
 
 def ReadTag(buffer, pos):
@@ -168,8 +183,10 @@ def ReadTag(buffer, pos):
   use that, but not in Python.
   """
 
+  py2 = _PY2  ##PY25
+##!PY25  py2 = str is bytes
   start = pos
-  while ord(buffer[pos]) & 0x80:
+  while (ord(buffer[pos]) if py2 else buffer[pos]) & 0x80:
     pos += 1
   pos += 1
   return (buffer[start:pos], pos)
@@ -284,6 +301,7 @@ def _FloatDecoder():
   """
 
   local_unpack = struct.unpack
+  b = (lambda x:x) if _PY2 else lambda x:x.encode('latin1')  ##PY25
 
   def InnerDecode(buffer, pos):
     # We expect a 32-bit value in little-endian byte order.  Bit 1 is the sign
@@ -294,13 +312,17 @@ def _FloatDecoder():
     # If this value has all its exponent bits set, then it's non-finite.
     # In Python 2.4, struct.unpack will convert it to a finite 64-bit value.
     # To avoid that, we parse it specially.
-    if ((float_bytes[3] in '\x7F\xFF')
-        and (float_bytes[2] >= '\x80')):
+    if ((float_bytes[3:4] in b('\x7F\xFF'))  ##PY25
+##!PY25    if ((float_bytes[3:4] in b'\x7F\xFF')
+        and (float_bytes[2:3] >= b('\x80'))):  ##PY25
+##!PY25        and (float_bytes[2:3] >= b'\x80')):
       # If at least one significand bit is set...
-      if float_bytes[0:3] != '\x00\x00\x80':
+      if float_bytes[0:3] != b('\x00\x00\x80'):  ##PY25
+##!PY25      if float_bytes[0:3] != b'\x00\x00\x80':
         return (_NAN, new_pos)
       # If sign bit is set...
-      if float_bytes[3] == '\xFF':
+      if float_bytes[3:4] == b('\xFF'):  ##PY25
+##!PY25      if float_bytes[3:4] == b'\xFF':
         return (_NEG_INF, new_pos)
       return (_POS_INF, new_pos)
 
@@ -319,6 +341,7 @@ def _DoubleDecoder():
   """
 
   local_unpack = struct.unpack
+  b = (lambda x:x) if _PY2 else lambda x:x.encode('latin1')  ##PY25
 
   def InnerDecode(buffer, pos):
     # We expect a 64-bit value in little-endian byte order.  Bit 1 is the sign
@@ -329,9 +352,12 @@ def _DoubleDecoder():
     # If this value has all its exponent bits set and at least one significand
     # bit set, it's not a number.  In Python 2.4, struct.unpack will treat it
     # as inf or -inf.  To avoid that, we treat it specially.
-    if ((double_bytes[7] in '\x7F\xFF')
-        and (double_bytes[6] >= '\xF0')
-        and (double_bytes[0:7] != '\x00\x00\x00\x00\x00\x00\xF0')):
+##!PY25    if ((double_bytes[7:8] in b'\x7F\xFF')
+##!PY25        and (double_bytes[6:7] >= b'\xF0')
+##!PY25        and (double_bytes[0:7] != b'\x00\x00\x00\x00\x00\x00\xF0')):
+    if ((double_bytes[7:8] in b('\x7F\xFF'))  ##PY25
+        and (double_bytes[6:7] >= b('\xF0'))  ##PY25
+        and (double_bytes[0:7] != b('\x00\x00\x00\x00\x00\x00\xF0'))):  ##PY25
       return (_NAN, new_pos)
 
     # Note that we expect someone up-stack to catch struct.error and convert
@@ -342,10 +368,86 @@ def _DoubleDecoder():
   return _SimpleDecoder(wire_format.WIRETYPE_FIXED64, InnerDecode)
 
 
+def EnumDecoder(field_number, is_repeated, is_packed, key, new_default):
+  enum_type = key.enum_type
+  if is_packed:
+    local_DecodeVarint = _DecodeVarint
+    def DecodePackedField(buffer, pos, end, message, field_dict):
+      value = field_dict.get(key)
+      if value is None:
+        value = field_dict.setdefault(key, new_default(message))
+      (endpoint, pos) = local_DecodeVarint(buffer, pos)
+      endpoint += pos
+      if endpoint > end:
+        raise _DecodeError('Truncated message.')
+      while pos < endpoint:
+        value_start_pos = pos
+        (element, pos) = _DecodeSignedVarint32(buffer, pos)
+        if element in enum_type.values_by_number:
+          value.append(element)
+        else:
+          if not message._unknown_fields:
+            message._unknown_fields = []
+          tag_bytes = encoder.TagBytes(field_number,
+                                       wire_format.WIRETYPE_VARINT)
+          message._unknown_fields.append(
+              (tag_bytes, buffer[value_start_pos:pos]))
+      if pos > endpoint:
+        if element in enum_type.values_by_number:
+          del value[-1]   # Discard corrupt value.
+        else:
+          del message._unknown_fields[-1]
+        raise _DecodeError('Packed element was truncated.')
+      return pos
+    return DecodePackedField
+  elif is_repeated:
+    tag_bytes = encoder.TagBytes(field_number, wire_format.WIRETYPE_VARINT)
+    tag_len = len(tag_bytes)
+    def DecodeRepeatedField(buffer, pos, end, message, field_dict):
+      value = field_dict.get(key)
+      if value is None:
+        value = field_dict.setdefault(key, new_default(message))
+      while 1:
+        (element, new_pos) = _DecodeSignedVarint32(buffer, pos)
+        if element in enum_type.values_by_number:
+          value.append(element)
+        else:
+          if not message._unknown_fields:
+            message._unknown_fields = []
+          message._unknown_fields.append(
+              (tag_bytes, buffer[pos:new_pos]))
+        # Predict that the next tag is another copy of the same repeated
+        # field.
+        pos = new_pos + tag_len
+        if buffer[new_pos:pos] != tag_bytes or new_pos >= end:
+          # Prediction failed.  Return.
+          if new_pos > end:
+            raise _DecodeError('Truncated message.')
+          return new_pos
+    return DecodeRepeatedField
+  else:
+    def DecodeField(buffer, pos, end, message, field_dict):
+      value_start_pos = pos
+      (enum_value, pos) = _DecodeSignedVarint32(buffer, pos)
+      if pos > end:
+        raise _DecodeError('Truncated message.')
+      if enum_value in enum_type.values_by_number:
+        field_dict[key] = enum_value
+      else:
+        if not message._unknown_fields:
+          message._unknown_fields = []
+        tag_bytes = encoder.TagBytes(field_number,
+                                     wire_format.WIRETYPE_VARINT)
+        message._unknown_fields.append(
+          (tag_bytes, buffer[value_start_pos:pos]))
+      return pos
+    return DecodeField
+
+
 # --------------------------------------------------------------------
 
 
-Int32Decoder = EnumDecoder = _SimpleDecoder(
+Int32Decoder = _SimpleDecoder(
     wire_format.WIRETYPE_VARINT, _DecodeSignedVarint32)
 
 Int64Decoder = _SimpleDecoder(
@@ -380,6 +482,14 @@ def StringDecoder(field_number, is_repeated, is_packed, key, new_default):
   local_DecodeVarint = _DecodeVarint
   local_unicode = unicode
 
+  def _ConvertToUnicode(byte_str):
+    try:
+      return local_unicode(byte_str, 'utf-8')
+    except UnicodeDecodeError, e:
+      # add more information to the error message and re-raise it.
+      e.reason = '%s in field: %s' % (e, key.full_name)
+      raise
+
   assert not is_packed
   if is_repeated:
     tag_bytes = encoder.TagBytes(field_number,
@@ -394,7 +504,7 @@ def StringDecoder(field_number, is_repeated, is_packed, key, new_default):
         new_pos = pos + size
         if new_pos > end:
           raise _DecodeError('Truncated string.')
-        value.append(local_unicode(buffer[pos:new_pos], 'utf-8'))
+        value.append(_ConvertToUnicode(buffer[pos:new_pos]))
         # Predict that the next tag is another copy of the same repeated field.
         pos = new_pos + tag_len
         if buffer[new_pos:pos] != tag_bytes or new_pos == end:
@@ -407,7 +517,7 @@ def StringDecoder(field_number, is_repeated, is_packed, key, new_default):
       new_pos = pos + size
       if new_pos > end:
         raise _DecodeError('Truncated string.')
-      field_dict[key] = local_unicode(buffer[pos:new_pos], 'utf-8')
+      field_dict[key] = _ConvertToUnicode(buffer[pos:new_pos])
       return new_pos
     return DecodeField
 
@@ -631,8 +741,10 @@ def MessageSetItemDecoder(extensions_by_number):
 
 def _SkipVarint(buffer, pos, end):
   """Skip a varint value.  Returns the new position."""
-
-  while ord(buffer[pos]) & 0x80:
+  # Previously ord(buffer[pos]) raised IndexError when pos is out of range.
+  # With this code, ord(b'') raises TypeError.  Both are handled in
+  # python_message.py to generate a 'Truncated message' error.
+  while ord(buffer[pos:pos+1]) & 0x80:
     pos += 1
   pos += 1
   if pos > end:
@@ -699,7 +811,6 @@ def _FieldSkipper():
       ]
 
   wiretype_mask = wire_format.TAG_TYPE_MASK
-  local_ord = ord
 
   def SkipField(buffer, pos, end, tag_bytes):
     """Skips a field with the specified tag.
@@ -712,7 +823,7 @@ def _FieldSkipper():
     """
 
     # The wire type is always in the first byte since varints are little-endian.
-    wire_type = local_ord(tag_bytes[0]) & wiretype_mask
+    wire_type = ord(tag_bytes[0:1]) & wiretype_mask
     return WIRETYPE_TO_SKIPPER[wire_type](buffer, pos, end)
 
   return SkipField
diff --git a/python/google/protobuf/internal/descriptor_cpp2_test.py b/python/google/protobuf/internal/descriptor_cpp2_test.py
new file mode 100644
index 00000000..3a3ff298
--- /dev/null
+++ b/python/google/protobuf/internal/descriptor_cpp2_test.py
@@ -0,0 +1,58 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Tests for google.protobuf.pyext behavior."""
+
+__author__ = 'anuraag@google.com (Anuraag Agrawal)'
+
+import os
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'cpp'
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION'] = '2'
+
+# We must set the implementation version above before the google3 imports.
+# pylint: disable=g-import-not-at-top
+from google.apputils import basetest
+from google.protobuf.internal import api_implementation
+# Run all tests from the original module by putting them in our namespace.
+# pylint: disable=wildcard-import
+from google.protobuf.internal.descriptor_test import *
+
+
+class ConfirmCppApi2Test(basetest.TestCase):
+
+  def testImplementationSetting(self):
+    self.assertEqual('cpp', api_implementation.Type())
+    self.assertEqual(2, api_implementation.Version())
+
+
+if __name__ == '__main__':
+  basetest.main()
diff --git a/python/google/protobuf/internal/descriptor_database_test.py b/python/google/protobuf/internal/descriptor_database_test.py
index d0ca7892..856f4723 100644
--- a/python/google/protobuf/internal/descriptor_database_test.py
+++ b/python/google/protobuf/internal/descriptor_database_test.py
@@ -34,13 +34,13 @@
 
 __author__ = 'matthewtoia@google.com (Matt Toia)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import descriptor_pb2
 from google.protobuf.internal import factory_test2_pb2
 from google.protobuf import descriptor_database
 
 
-class DescriptorDatabaseTest(unittest.TestCase):
+class DescriptorDatabaseTest(basetest.TestCase):
 
   def testAdd(self):
     db = descriptor_database.DescriptorDatabase()
@@ -49,15 +49,15 @@ class DescriptorDatabaseTest(unittest.TestCase):
     db.Add(file_desc_proto)
 
     self.assertEquals(file_desc_proto, db.FindFileByName(
-        'net/proto2/python/internal/factory_test2.proto'))
+        'google/protobuf/internal/factory_test2.proto'))
     self.assertEquals(file_desc_proto, db.FindFileContainingSymbol(
-        'net.proto2.python.internal.Factory2Message'))
+        'google.protobuf.python.internal.Factory2Message'))
     self.assertEquals(file_desc_proto, db.FindFileContainingSymbol(
-        'net.proto2.python.internal.Factory2Message.NestedFactory2Message'))
+        'google.protobuf.python.internal.Factory2Message.NestedFactory2Message'))
     self.assertEquals(file_desc_proto, db.FindFileContainingSymbol(
-        'net.proto2.python.internal.Factory2Enum'))
+        'google.protobuf.python.internal.Factory2Enum'))
     self.assertEquals(file_desc_proto, db.FindFileContainingSymbol(
-        'net.proto2.python.internal.Factory2Message.NestedFactory2Enum'))
+        'google.protobuf.python.internal.Factory2Message.NestedFactory2Enum'))
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/descriptor_pool_test.py b/python/google/protobuf/internal/descriptor_pool_test.py
index a615d787..7c1ce2e1 100644
--- a/python/google/protobuf/internal/descriptor_pool_test.py
+++ b/python/google/protobuf/internal/descriptor_pool_test.py
@@ -34,8 +34,15 @@
 
 __author__ = 'matthewtoia@google.com (Matt Toia)'
 
+import os
 import unittest
+
+from google.apputils import basetest
+from google.protobuf import unittest_pb2
 from google.protobuf import descriptor_pb2
+from google.protobuf.internal import api_implementation
+from google.protobuf.internal import descriptor_pool_test1_pb2
+from google.protobuf.internal import descriptor_pool_test2_pb2
 from google.protobuf.internal import factory_test1_pb2
 from google.protobuf.internal import factory_test2_pb2
 from google.protobuf import descriptor
@@ -43,7 +50,7 @@ from google.protobuf import descriptor_database
 from google.protobuf import descriptor_pool
 
 
-class DescriptorPoolTest(unittest.TestCase):
+class DescriptorPoolTest(basetest.TestCase):
 
   def setUp(self):
     self.pool = descriptor_pool.DescriptorPool()
@@ -55,57 +62,51 @@ class DescriptorPoolTest(unittest.TestCase):
     self.pool.Add(self.factory_test2_fd)
 
   def testFindFileByName(self):
-    name1 = 'net/proto2/python/internal/factory_test1.proto'
+    name1 = 'google/protobuf/internal/factory_test1.proto'
     file_desc1 = self.pool.FindFileByName(name1)
     self.assertIsInstance(file_desc1, descriptor.FileDescriptor)
     self.assertEquals(name1, file_desc1.name)
-    self.assertEquals('net.proto2.python.internal', file_desc1.package)
+    self.assertEquals('google.protobuf.python.internal', file_desc1.package)
     self.assertIn('Factory1Message', file_desc1.message_types_by_name)
 
-    name2 = 'net/proto2/python/internal/factory_test2.proto'
+    name2 = 'google/protobuf/internal/factory_test2.proto'
     file_desc2 = self.pool.FindFileByName(name2)
     self.assertIsInstance(file_desc2, descriptor.FileDescriptor)
     self.assertEquals(name2, file_desc2.name)
-    self.assertEquals('net.proto2.python.internal', file_desc2.package)
+    self.assertEquals('google.protobuf.python.internal', file_desc2.package)
     self.assertIn('Factory2Message', file_desc2.message_types_by_name)
 
   def testFindFileByNameFailure(self):
-    try:
+    with self.assertRaises(KeyError):
       self.pool.FindFileByName('Does not exist')
-      self.fail('Expected KeyError')
-    except KeyError:
-      pass
 
   def testFindFileContainingSymbol(self):
     file_desc1 = self.pool.FindFileContainingSymbol(
-        'net.proto2.python.internal.Factory1Message')
+        'google.protobuf.python.internal.Factory1Message')
     self.assertIsInstance(file_desc1, descriptor.FileDescriptor)
-    self.assertEquals('net/proto2/python/internal/factory_test1.proto',
+    self.assertEquals('google/protobuf/internal/factory_test1.proto',
                       file_desc1.name)
-    self.assertEquals('net.proto2.python.internal', file_desc1.package)
+    self.assertEquals('google.protobuf.python.internal', file_desc1.package)
     self.assertIn('Factory1Message', file_desc1.message_types_by_name)
 
     file_desc2 = self.pool.FindFileContainingSymbol(
-        'net.proto2.python.internal.Factory2Message')
+        'google.protobuf.python.internal.Factory2Message')
     self.assertIsInstance(file_desc2, descriptor.FileDescriptor)
-    self.assertEquals('net/proto2/python/internal/factory_test2.proto',
+    self.assertEquals('google/protobuf/internal/factory_test2.proto',
                       file_desc2.name)
-    self.assertEquals('net.proto2.python.internal', file_desc2.package)
+    self.assertEquals('google.protobuf.python.internal', file_desc2.package)
     self.assertIn('Factory2Message', file_desc2.message_types_by_name)
 
   def testFindFileContainingSymbolFailure(self):
-    try:
+    with self.assertRaises(KeyError):
       self.pool.FindFileContainingSymbol('Does not exist')
-      self.fail('Expected KeyError')
-    except KeyError:
-      pass
 
   def testFindMessageTypeByName(self):
     msg1 = self.pool.FindMessageTypeByName(
-        'net.proto2.python.internal.Factory1Message')
+        'google.protobuf.python.internal.Factory1Message')
     self.assertIsInstance(msg1, descriptor.Descriptor)
     self.assertEquals('Factory1Message', msg1.name)
-    self.assertEquals('net.proto2.python.internal.Factory1Message',
+    self.assertEquals('google.protobuf.python.internal.Factory1Message',
                       msg1.full_name)
     self.assertEquals(None, msg1.containing_type)
 
@@ -123,10 +124,10 @@ class DescriptorPoolTest(unittest.TestCase):
         'nested_factory_1_enum'].enum_type)
 
     msg2 = self.pool.FindMessageTypeByName(
-        'net.proto2.python.internal.Factory2Message')
+        'google.protobuf.python.internal.Factory2Message')
     self.assertIsInstance(msg2, descriptor.Descriptor)
     self.assertEquals('Factory2Message', msg2.name)
-    self.assertEquals('net.proto2.python.internal.Factory2Message',
+    self.assertEquals('google.protobuf.python.internal.Factory2Message',
                       msg2.full_name)
     self.assertIsNone(msg2.containing_type)
 
@@ -143,45 +144,57 @@ class DescriptorPoolTest(unittest.TestCase):
     self.assertEquals(nested_enum2, msg2.fields_by_name[
         'nested_factory_2_enum'].enum_type)
 
-    self.assertTrue(msg2.fields_by_name['int_with_default'].has_default)
+    self.assertTrue(msg2.fields_by_name['int_with_default'].has_default_value)
     self.assertEquals(
         1776, msg2.fields_by_name['int_with_default'].default_value)
 
-    self.assertTrue(msg2.fields_by_name['double_with_default'].has_default)
+    self.assertTrue(
+        msg2.fields_by_name['double_with_default'].has_default_value)
     self.assertEquals(
         9.99, msg2.fields_by_name['double_with_default'].default_value)
 
-    self.assertTrue(msg2.fields_by_name['string_with_default'].has_default)
+    self.assertTrue(
+        msg2.fields_by_name['string_with_default'].has_default_value)
     self.assertEquals(
         'hello world', msg2.fields_by_name['string_with_default'].default_value)
 
-    self.assertTrue(msg2.fields_by_name['bool_with_default'].has_default)
+    self.assertTrue(msg2.fields_by_name['bool_with_default'].has_default_value)
     self.assertFalse(msg2.fields_by_name['bool_with_default'].default_value)
 
-    self.assertTrue(msg2.fields_by_name['enum_with_default'].has_default)
+    self.assertTrue(msg2.fields_by_name['enum_with_default'].has_default_value)
     self.assertEquals(
         1, msg2.fields_by_name['enum_with_default'].default_value)
 
     msg3 = self.pool.FindMessageTypeByName(
-        'net.proto2.python.internal.Factory2Message.NestedFactory2Message')
+        'google.protobuf.python.internal.Factory2Message.NestedFactory2Message')
     self.assertEquals(nested_msg2, msg3)
 
+    self.assertTrue(msg2.fields_by_name['bytes_with_default'].has_default_value)
+    self.assertEquals(
+        b'a\xfb\x00c',
+        msg2.fields_by_name['bytes_with_default'].default_value)
+
+    self.assertEqual(1, len(msg2.oneofs))
+    self.assertEqual(1, len(msg2.oneofs_by_name))
+    self.assertEqual(2, len(msg2.oneofs[0].fields))
+    for name in ['oneof_int', 'oneof_string']:
+      self.assertEqual(msg2.oneofs[0],
+                       msg2.fields_by_name[name].containing_oneof)
+      self.assertIn(msg2.fields_by_name[name], msg2.oneofs[0].fields)
+
   def testFindMessageTypeByNameFailure(self):
-    try:
+    with self.assertRaises(KeyError):
       self.pool.FindMessageTypeByName('Does not exist')
-      self.fail('Expected KeyError')
-    except KeyError:
-      pass
 
   def testFindEnumTypeByName(self):
     enum1 = self.pool.FindEnumTypeByName(
-        'net.proto2.python.internal.Factory1Enum')
+        'google.protobuf.python.internal.Factory1Enum')
     self.assertIsInstance(enum1, descriptor.EnumDescriptor)
     self.assertEquals(0, enum1.values_by_name['FACTORY_1_VALUE_0'].number)
     self.assertEquals(1, enum1.values_by_name['FACTORY_1_VALUE_1'].number)
 
     nested_enum1 = self.pool.FindEnumTypeByName(
-        'net.proto2.python.internal.Factory1Message.NestedFactory1Enum')
+        'google.protobuf.python.internal.Factory1Message.NestedFactory1Enum')
     self.assertIsInstance(nested_enum1, descriptor.EnumDescriptor)
     self.assertEquals(
         0, nested_enum1.values_by_name['NESTED_FACTORY_1_VALUE_0'].number)
@@ -189,13 +202,13 @@ class DescriptorPoolTest(unittest.TestCase):
         1, nested_enum1.values_by_name['NESTED_FACTORY_1_VALUE_1'].number)
 
     enum2 = self.pool.FindEnumTypeByName(
-        'net.proto2.python.internal.Factory2Enum')
+        'google.protobuf.python.internal.Factory2Enum')
     self.assertIsInstance(enum2, descriptor.EnumDescriptor)
     self.assertEquals(0, enum2.values_by_name['FACTORY_2_VALUE_0'].number)
     self.assertEquals(1, enum2.values_by_name['FACTORY_2_VALUE_1'].number)
 
     nested_enum2 = self.pool.FindEnumTypeByName(
-        'net.proto2.python.internal.Factory2Message.NestedFactory2Enum')
+        'google.protobuf.python.internal.Factory2Message.NestedFactory2Enum')
     self.assertIsInstance(nested_enum2, descriptor.EnumDescriptor)
     self.assertEquals(
         0, nested_enum2.values_by_name['NESTED_FACTORY_2_VALUE_0'].number)
@@ -203,11 +216,8 @@ class DescriptorPoolTest(unittest.TestCase):
         1, nested_enum2.values_by_name['NESTED_FACTORY_2_VALUE_1'].number)
 
   def testFindEnumTypeByNameFailure(self):
-    try:
+    with self.assertRaises(KeyError):
       self.pool.FindEnumTypeByName('Does not exist')
-      self.fail('Expected KeyError')
-    except KeyError:
-      pass
 
   def testUserDefinedDB(self):
     db = descriptor_database.DescriptorDatabase()
@@ -216,5 +226,339 @@ class DescriptorPoolTest(unittest.TestCase):
     db.Add(self.factory_test2_fd)
     self.testFindMessageTypeByName()
 
+  def testComplexNesting(self):
+    test1_desc = descriptor_pb2.FileDescriptorProto.FromString(
+        descriptor_pool_test1_pb2.DESCRIPTOR.serialized_pb)
+    test2_desc = descriptor_pb2.FileDescriptorProto.FromString(
+        descriptor_pool_test2_pb2.DESCRIPTOR.serialized_pb)
+    self.pool.Add(test1_desc)
+    self.pool.Add(test2_desc)
+    TEST1_FILE.CheckFile(self, self.pool)
+    TEST2_FILE.CheckFile(self, self.pool)
+
+
+
+class ProtoFile(object):
+
+  def __init__(self, name, package, messages, dependencies=None):
+    self.name = name
+    self.package = package
+    self.messages = messages
+    self.dependencies = dependencies or []
+
+  def CheckFile(self, test, pool):
+    file_desc = pool.FindFileByName(self.name)
+    test.assertEquals(self.name, file_desc.name)
+    test.assertEquals(self.package, file_desc.package)
+    dependencies_names = [f.name for f in file_desc.dependencies]
+    test.assertEqual(self.dependencies, dependencies_names)
+    for name, msg_type in self.messages.items():
+      msg_type.CheckType(test, None, name, file_desc)
+
+
+class EnumType(object):
+
+  def __init__(self, values):
+    self.values = values
+
+  def CheckType(self, test, msg_desc, name, file_desc):
+    enum_desc = msg_desc.enum_types_by_name[name]
+    test.assertEqual(name, enum_desc.name)
+    expected_enum_full_name = '.'.join([msg_desc.full_name, name])
+    test.assertEqual(expected_enum_full_name, enum_desc.full_name)
+    test.assertEqual(msg_desc, enum_desc.containing_type)
+    test.assertEqual(file_desc, enum_desc.file)
+    for index, (value, number) in enumerate(self.values):
+      value_desc = enum_desc.values_by_name[value]
+      test.assertEqual(value, value_desc.name)
+      test.assertEqual(index, value_desc.index)
+      test.assertEqual(number, value_desc.number)
+      test.assertEqual(enum_desc, value_desc.type)
+      test.assertIn(value, msg_desc.enum_values_by_name)
+
+
+class MessageType(object):
+
+  def __init__(self, type_dict, field_list, is_extendable=False,
+               extensions=None):
+    self.type_dict = type_dict
+    self.field_list = field_list
+    self.is_extendable = is_extendable
+    self.extensions = extensions or []
+
+  def CheckType(self, test, containing_type_desc, name, file_desc):
+    if containing_type_desc is None:
+      desc = file_desc.message_types_by_name[name]
+      expected_full_name = '.'.join([file_desc.package, name])
+    else:
+      desc = containing_type_desc.nested_types_by_name[name]
+      expected_full_name = '.'.join([containing_type_desc.full_name, name])
+
+    test.assertEqual(name, desc.name)
+    test.assertEqual(expected_full_name, desc.full_name)
+    test.assertEqual(containing_type_desc, desc.containing_type)
+    test.assertEqual(desc.file, file_desc)
+    test.assertEqual(self.is_extendable, desc.is_extendable)
+    for name, subtype in self.type_dict.items():
+      subtype.CheckType(test, desc, name, file_desc)
+
+    for index, (name, field) in enumerate(self.field_list):
+      field.CheckField(test, desc, name, index)
+
+    for index, (name, field) in enumerate(self.extensions):
+      field.CheckField(test, desc, name, index)
+
+
+class EnumField(object):
+
+  def __init__(self, number, type_name, default_value):
+    self.number = number
+    self.type_name = type_name
+    self.default_value = default_value
+
+  def CheckField(self, test, msg_desc, name, index):
+    field_desc = msg_desc.fields_by_name[name]
+    enum_desc = msg_desc.enum_types_by_name[self.type_name]
+    test.assertEqual(name, field_desc.name)
+    expected_field_full_name = '.'.join([msg_desc.full_name, name])
+    test.assertEqual(expected_field_full_name, field_desc.full_name)
+    test.assertEqual(index, field_desc.index)
+    test.assertEqual(self.number, field_desc.number)
+    test.assertEqual(descriptor.FieldDescriptor.TYPE_ENUM, field_desc.type)
+    test.assertEqual(descriptor.FieldDescriptor.CPPTYPE_ENUM,
+                     field_desc.cpp_type)
+    test.assertTrue(field_desc.has_default_value)
+    test.assertEqual(enum_desc.values_by_name[self.default_value].index,
+                     field_desc.default_value)
+    test.assertEqual(msg_desc, field_desc.containing_type)
+    test.assertEqual(enum_desc, field_desc.enum_type)
+
+
+class MessageField(object):
+
+  def __init__(self, number, type_name):
+    self.number = number
+    self.type_name = type_name
+
+  def CheckField(self, test, msg_desc, name, index):
+    field_desc = msg_desc.fields_by_name[name]
+    field_type_desc = msg_desc.nested_types_by_name[self.type_name]
+    test.assertEqual(name, field_desc.name)
+    expected_field_full_name = '.'.join([msg_desc.full_name, name])
+    test.assertEqual(expected_field_full_name, field_desc.full_name)
+    test.assertEqual(index, field_desc.index)
+    test.assertEqual(self.number, field_desc.number)
+    test.assertEqual(descriptor.FieldDescriptor.TYPE_MESSAGE, field_desc.type)
+    test.assertEqual(descriptor.FieldDescriptor.CPPTYPE_MESSAGE,
+                     field_desc.cpp_type)
+    test.assertFalse(field_desc.has_default_value)
+    test.assertEqual(msg_desc, field_desc.containing_type)
+    test.assertEqual(field_type_desc, field_desc.message_type)
+
+
+class StringField(object):
+
+  def __init__(self, number, default_value):
+    self.number = number
+    self.default_value = default_value
+
+  def CheckField(self, test, msg_desc, name, index):
+    field_desc = msg_desc.fields_by_name[name]
+    test.assertEqual(name, field_desc.name)
+    expected_field_full_name = '.'.join([msg_desc.full_name, name])
+    test.assertEqual(expected_field_full_name, field_desc.full_name)
+    test.assertEqual(index, field_desc.index)
+    test.assertEqual(self.number, field_desc.number)
+    test.assertEqual(descriptor.FieldDescriptor.TYPE_STRING, field_desc.type)
+    test.assertEqual(descriptor.FieldDescriptor.CPPTYPE_STRING,
+                     field_desc.cpp_type)
+    test.assertTrue(field_desc.has_default_value)
+    test.assertEqual(self.default_value, field_desc.default_value)
+
+
+class ExtensionField(object):
+
+  def __init__(self, number, extended_type):
+    self.number = number
+    self.extended_type = extended_type
+
+  def CheckField(self, test, msg_desc, name, index):
+    field_desc = msg_desc.extensions_by_name[name]
+    test.assertEqual(name, field_desc.name)
+    expected_field_full_name = '.'.join([msg_desc.full_name, name])
+    test.assertEqual(expected_field_full_name, field_desc.full_name)
+    test.assertEqual(self.number, field_desc.number)
+    test.assertEqual(index, field_desc.index)
+    test.assertEqual(descriptor.FieldDescriptor.TYPE_MESSAGE, field_desc.type)
+    test.assertEqual(descriptor.FieldDescriptor.CPPTYPE_MESSAGE,
+                     field_desc.cpp_type)
+    test.assertFalse(field_desc.has_default_value)
+    test.assertTrue(field_desc.is_extension)
+    test.assertEqual(msg_desc, field_desc.extension_scope)
+    test.assertEqual(msg_desc, field_desc.message_type)
+    test.assertEqual(self.extended_type, field_desc.containing_type.name)
+
+
+class AddDescriptorTest(basetest.TestCase):
+
+  def _TestMessage(self, prefix):
+    pool = descriptor_pool.DescriptorPool()
+    pool.AddDescriptor(unittest_pb2.TestAllTypes.DESCRIPTOR)
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes',
+        pool.FindMessageTypeByName(
+            prefix + 'protobuf_unittest.TestAllTypes').full_name)
+
+    # AddDescriptor is not recursive.
+    with self.assertRaises(KeyError):
+      pool.FindMessageTypeByName(
+          prefix + 'protobuf_unittest.TestAllTypes.NestedMessage')
+
+    pool.AddDescriptor(unittest_pb2.TestAllTypes.NestedMessage.DESCRIPTOR)
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes.NestedMessage',
+        pool.FindMessageTypeByName(
+            prefix + 'protobuf_unittest.TestAllTypes.NestedMessage').full_name)
+
+    # Files are implicitly also indexed when messages are added.
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        pool.FindFileByName(
+            'google/protobuf/unittest.proto').name)
+
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        pool.FindFileContainingSymbol(
+            prefix + 'protobuf_unittest.TestAllTypes.NestedMessage').name)
+
+  def testMessage(self):
+    self._TestMessage('')
+    self._TestMessage('.')
+
+  def _TestEnum(self, prefix):
+    pool = descriptor_pool.DescriptorPool()
+    pool.AddEnumDescriptor(unittest_pb2.ForeignEnum.DESCRIPTOR)
+    self.assertEquals(
+        'protobuf_unittest.ForeignEnum',
+        pool.FindEnumTypeByName(
+            prefix + 'protobuf_unittest.ForeignEnum').full_name)
+
+    # AddEnumDescriptor is not recursive.
+    with self.assertRaises(KeyError):
+      pool.FindEnumTypeByName(
+          prefix + 'protobuf_unittest.ForeignEnum.NestedEnum')
+
+    pool.AddEnumDescriptor(unittest_pb2.TestAllTypes.NestedEnum.DESCRIPTOR)
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes.NestedEnum',
+        pool.FindEnumTypeByName(
+            prefix + 'protobuf_unittest.TestAllTypes.NestedEnum').full_name)
+
+    # Files are implicitly also indexed when enums are added.
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        pool.FindFileByName(
+            'google/protobuf/unittest.proto').name)
+
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        pool.FindFileContainingSymbol(
+            prefix + 'protobuf_unittest.TestAllTypes.NestedEnum').name)
+
+  def testEnum(self):
+    self._TestEnum('')
+    self._TestEnum('.')
+
+  def testFile(self):
+    pool = descriptor_pool.DescriptorPool()
+    pool.AddFileDescriptor(unittest_pb2.DESCRIPTOR)
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        pool.FindFileByName(
+            'google/protobuf/unittest.proto').name)
+
+    # AddFileDescriptor is not recursive; messages and enums within files must
+    # be explicitly registered.
+    with self.assertRaises(KeyError):
+      pool.FindFileContainingSymbol(
+          'protobuf_unittest.TestAllTypes')
+
+
+TEST1_FILE = ProtoFile(
+    'google/protobuf/internal/descriptor_pool_test1.proto',
+    'google.protobuf.python.internal',
+    {
+        'DescriptorPoolTest1': MessageType({
+            'NestedEnum': EnumType([('ALPHA', 1), ('BETA', 2)]),
+            'NestedMessage': MessageType({
+                'NestedEnum': EnumType([('EPSILON', 5), ('ZETA', 6)]),
+                'DeepNestedMessage': MessageType({
+                    'NestedEnum': EnumType([('ETA', 7), ('THETA', 8)]),
+                }, [
+                    ('nested_enum', EnumField(1, 'NestedEnum', 'ETA')),
+                    ('nested_field', StringField(2, 'theta')),
+                ]),
+            }, [
+                ('nested_enum', EnumField(1, 'NestedEnum', 'ZETA')),
+                ('nested_field', StringField(2, 'beta')),
+                ('deep_nested_message', MessageField(3, 'DeepNestedMessage')),
+            ])
+        }, [
+            ('nested_enum', EnumField(1, 'NestedEnum', 'BETA')),
+            ('nested_message', MessageField(2, 'NestedMessage')),
+        ], is_extendable=True),
+
+        'DescriptorPoolTest2': MessageType({
+            'NestedEnum': EnumType([('GAMMA', 3), ('DELTA', 4)]),
+            'NestedMessage': MessageType({
+                'NestedEnum': EnumType([('IOTA', 9), ('KAPPA', 10)]),
+                'DeepNestedMessage': MessageType({
+                    'NestedEnum': EnumType([('LAMBDA', 11), ('MU', 12)]),
+                }, [
+                    ('nested_enum', EnumField(1, 'NestedEnum', 'MU')),
+                    ('nested_field', StringField(2, 'lambda')),
+                ]),
+            }, [
+                ('nested_enum', EnumField(1, 'NestedEnum', 'IOTA')),
+                ('nested_field', StringField(2, 'delta')),
+                ('deep_nested_message', MessageField(3, 'DeepNestedMessage')),
+            ])
+        }, [
+            ('nested_enum', EnumField(1, 'NestedEnum', 'GAMMA')),
+            ('nested_message', MessageField(2, 'NestedMessage')),
+        ]),
+    })
+
+
+TEST2_FILE = ProtoFile(
+    'google/protobuf/internal/descriptor_pool_test2.proto',
+    'google.protobuf.python.internal',
+    {
+        'DescriptorPoolTest3': MessageType({
+            'NestedEnum': EnumType([('NU', 13), ('XI', 14)]),
+            'NestedMessage': MessageType({
+                'NestedEnum': EnumType([('OMICRON', 15), ('PI', 16)]),
+                'DeepNestedMessage': MessageType({
+                    'NestedEnum': EnumType([('RHO', 17), ('SIGMA', 18)]),
+                }, [
+                    ('nested_enum', EnumField(1, 'NestedEnum', 'RHO')),
+                    ('nested_field', StringField(2, 'sigma')),
+                ]),
+            }, [
+                ('nested_enum', EnumField(1, 'NestedEnum', 'PI')),
+                ('nested_field', StringField(2, 'nu')),
+                ('deep_nested_message', MessageField(3, 'DeepNestedMessage')),
+            ])
+        }, [
+            ('nested_enum', EnumField(1, 'NestedEnum', 'XI')),
+            ('nested_message', MessageField(2, 'NestedMessage')),
+        ], extensions=[
+            ('descriptor_pool_test',
+             ExtensionField(1001, 'DescriptorPoolTest1')),
+        ]),
+    },
+    dependencies=['google/protobuf/internal/descriptor_pool_test1.proto'])
+
+
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/descriptor_pool_test1.proto b/python/google/protobuf/internal/descriptor_pool_test1.proto
new file mode 100644
index 00000000..c11dcc0e
--- /dev/null
+++ b/python/google/protobuf/internal/descriptor_pool_test1.proto
@@ -0,0 +1,94 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package google.protobuf.python.internal;
+
+
+message DescriptorPoolTest1 {
+  extensions 1000 to max;
+
+  enum NestedEnum {
+    ALPHA = 1;
+    BETA = 2;
+  }
+
+  optional NestedEnum nested_enum = 1 [default = BETA];
+
+  message NestedMessage {
+    enum NestedEnum {
+      EPSILON = 5;
+      ZETA = 6;
+    }
+    optional NestedEnum nested_enum = 1 [default = ZETA];
+    optional string nested_field = 2 [default = "beta"];
+    optional DeepNestedMessage deep_nested_message = 3;
+
+    message DeepNestedMessage {
+      enum NestedEnum {
+        ETA = 7;
+        THETA = 8;
+      }
+      optional NestedEnum nested_enum = 1 [default = ETA];
+      optional string nested_field = 2 [default = "theta"];
+    }
+  }
+
+  optional NestedMessage nested_message = 2;
+}
+
+message DescriptorPoolTest2 {
+  enum NestedEnum {
+    GAMMA = 3;
+    DELTA = 4;
+  }
+
+  optional NestedEnum nested_enum = 1 [default = GAMMA];
+
+  message NestedMessage {
+    enum NestedEnum {
+      IOTA = 9;
+      KAPPA = 10;
+    }
+    optional NestedEnum nested_enum = 1 [default = IOTA];
+    optional string nested_field = 2 [default = "delta"];
+    optional DeepNestedMessage deep_nested_message = 3;
+
+    message DeepNestedMessage {
+      enum NestedEnum {
+        LAMBDA = 11;
+        MU = 12;
+      }
+      optional NestedEnum nested_enum = 1 [default = MU];
+      optional string nested_field = 2 [default = "lambda"];
+    }
+  }
+
+  optional NestedMessage nested_message = 2;
+}
diff --git a/python/google/protobuf/internal/descriptor_pool_test2.proto b/python/google/protobuf/internal/descriptor_pool_test2.proto
new file mode 100644
index 00000000..d97d39b4
--- /dev/null
+++ b/python/google/protobuf/internal/descriptor_pool_test2.proto
@@ -0,0 +1,70 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package google.protobuf.python.internal;
+
+import "google/protobuf/internal/descriptor_pool_test1.proto";
+
+
+message DescriptorPoolTest3 {
+
+  extend DescriptorPoolTest1 {
+    optional DescriptorPoolTest3 descriptor_pool_test = 1001;
+  }
+
+  enum NestedEnum {
+    NU = 13;
+    XI = 14;
+  }
+
+  optional NestedEnum nested_enum = 1 [default = XI];
+
+  message NestedMessage {
+    enum NestedEnum {
+      OMICRON = 15;
+      PI = 16;
+    }
+    optional NestedEnum nested_enum = 1 [default = PI];
+    optional string nested_field = 2 [default = "nu"];
+    optional DeepNestedMessage deep_nested_message = 3;
+
+    message DeepNestedMessage {
+      enum NestedEnum {
+        RHO = 17;
+        SIGMA = 18;
+      }
+      optional NestedEnum nested_enum = 1 [default = RHO];
+      optional string nested_field = 2 [default = "sigma"];
+    }
+  }
+
+  optional NestedMessage nested_message = 2;
+}
+
diff --git a/python/google/protobuf/internal/descriptor_python_test.py b/python/google/protobuf/internal/descriptor_python_test.py
new file mode 100644
index 00000000..b3a15710
--- /dev/null
+++ b/python/google/protobuf/internal/descriptor_python_test.py
@@ -0,0 +1,54 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Unittest for descriptor.py for the pure Python implementation."""
+
+import os
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'python'
+
+# We must set the implementation version above before the google3 imports.
+# pylint: disable=g-import-not-at-top
+from google.apputils import basetest
+from google.protobuf.internal import api_implementation
+# Run all tests from the original module by putting them in our namespace.
+# pylint: disable=wildcard-import
+from google.protobuf.internal.descriptor_test import *
+
+
+class ConfirmPurePythonTest(basetest.TestCase):
+
+  def testImplementationSetting(self):
+    self.assertEqual('python', api_implementation.Type())
+
+
+if __name__ == '__main__':
+  basetest.main()
diff --git a/python/google/protobuf/internal/descriptor_test.py b/python/google/protobuf/internal/descriptor_test.py
index c74f882e..d20d9457 100755
--- a/python/google/protobuf/internal/descriptor_test.py
+++ b/python/google/protobuf/internal/descriptor_test.py
@@ -34,7 +34,7 @@
 
 __author__ = 'robinson@google.com (Will Robinson)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import unittest_custom_options_pb2
 from google.protobuf import unittest_import_pb2
 from google.protobuf import unittest_pb2
@@ -48,7 +48,7 @@ name: 'TestEmptyMessage'
 """
 
 
-class DescriptorTest(unittest.TestCase):
+class DescriptorTest(basetest.TestCase):
 
   def setUp(self):
     self.my_file = descriptor.FileDescriptor(
@@ -244,7 +244,7 @@ class DescriptorTest(unittest.TestCase):
         unittest_custom_options_pb2.double_opt])
     self.assertEqual("Hello, \"World\"", message_options.Extensions[
         unittest_custom_options_pb2.string_opt])
-    self.assertEqual("Hello\0World", message_options.Extensions[
+    self.assertEqual(b"Hello\0World", message_options.Extensions[
         unittest_custom_options_pb2.bytes_opt])
     dummy_enum = unittest_custom_options_pb2.DummyMessageContainingEnum
     self.assertEqual(
@@ -395,7 +395,7 @@ class DescriptorTest(unittest.TestCase):
     self.assertEqual(self.my_file.package, 'protobuf_unittest')
 
 
-class DescriptorCopyToProtoTest(unittest.TestCase):
+class DescriptorCopyToProtoTest(basetest.TestCase):
   """Tests for CopyTo functions of Descriptor."""
 
   def _AssertProtoEqual(self, actual_proto, expected_class, expected_ascii):
@@ -530,47 +530,49 @@ class DescriptorCopyToProtoTest(unittest.TestCase):
         descriptor_pb2.DescriptorProto,
         TEST_MESSAGE_WITH_SEVERAL_EXTENSIONS_ASCII)
 
-  def testCopyToProto_FileDescriptor(self):
-    UNITTEST_IMPORT_FILE_DESCRIPTOR_ASCII = ("""
-      name: 'google/protobuf/unittest_import.proto'
-      package: 'protobuf_unittest_import'
-      dependency: 'google/protobuf/unittest_import_public.proto'
-      message_type: <
-        name: 'ImportMessage'
-        field: <
-          name: 'd'
-          number: 1
-          label: 1  # Optional
-          type: 5  # TYPE_INT32
-        >
-      >
-      """ +
-      """enum_type: <
-        name: 'ImportEnum'
-        value: <
-          name: 'IMPORT_FOO'
-          number: 7
-        >
-        value: <
-          name: 'IMPORT_BAR'
-          number: 8
-        >
-        value: <
-          name: 'IMPORT_BAZ'
-          number: 9
-        >
-      >
-      options: <
-        java_package: 'com.google.protobuf.test'
-        optimize_for: 1  # SPEED
-      >
-      public_dependency: 0
-      """)
-
-    self._InternalTestCopyToProto(
-        unittest_import_pb2.DESCRIPTOR,
-        descriptor_pb2.FileDescriptorProto,
-        UNITTEST_IMPORT_FILE_DESCRIPTOR_ASCII)
+  # Disable this test so we can make changes to the proto file.
+  # TODO(xiaofeng): Enable this test after cl/55530659 is submitted.
+  #
+  # def testCopyToProto_FileDescriptor(self):
+  #   UNITTEST_IMPORT_FILE_DESCRIPTOR_ASCII = ("""
+  #     name: 'google/protobuf/unittest_import.proto'
+  #     package: 'protobuf_unittest_import'
+  #     dependency: 'google/protobuf/unittest_import_public.proto'
+  #     message_type: <
+  #       name: 'ImportMessage'
+  #       field: <
+  #         name: 'd'
+  #         number: 1
+  #         label: 1  # Optional
+  #         type: 5  # TYPE_INT32
+  #       >
+  #     >
+  #     """ +
+  #     """enum_type: <
+  #       name: 'ImportEnum'
+  #       value: <
+  #         name: 'IMPORT_FOO'
+  #         number: 7
+  #       >
+  #       value: <
+  #         name: 'IMPORT_BAR'
+  #         number: 8
+  #       >
+  #       value: <
+  #         name: 'IMPORT_BAZ'
+  #         number: 9
+  #       >
+  #     >
+  #     options: <
+  #       java_package: 'com.google.protobuf.test'
+  #       optimize_for: 1  # SPEED
+  #     >
+  #     public_dependency: 0
+  #  """)
+  #  self._InternalTestCopyToProto(
+  #      unittest_import_pb2.DESCRIPTOR,
+  #      descriptor_pb2.FileDescriptorProto,
+  #      UNITTEST_IMPORT_FILE_DESCRIPTOR_ASCII)
 
   def testCopyToProto_ServiceDescriptor(self):
     TEST_SERVICE_ASCII = """
@@ -586,28 +588,82 @@ class DescriptorCopyToProtoTest(unittest.TestCase):
         output_type: '.protobuf_unittest.BarResponse'
       >
       """
-
     self._InternalTestCopyToProto(
         unittest_pb2.TestService.DESCRIPTOR,
         descriptor_pb2.ServiceDescriptorProto,
         TEST_SERVICE_ASCII)
 
 
-class MakeDescriptorTest(unittest.TestCase):
+class MakeDescriptorTest(basetest.TestCase):
+
+  def testMakeDescriptorWithNestedFields(self):
+    file_descriptor_proto = descriptor_pb2.FileDescriptorProto()
+    file_descriptor_proto.name = 'Foo2'
+    message_type = file_descriptor_proto.message_type.add()
+    message_type.name = file_descriptor_proto.name
+    nested_type = message_type.nested_type.add()
+    nested_type.name = 'Sub'
+    enum_type = nested_type.enum_type.add()
+    enum_type.name = 'FOO'
+    enum_type_val = enum_type.value.add()
+    enum_type_val.name = 'BAR'
+    enum_type_val.number = 3
+    field = message_type.field.add()
+    field.number = 1
+    field.name = 'uint64_field'
+    field.label = descriptor.FieldDescriptor.LABEL_REQUIRED
+    field.type = descriptor.FieldDescriptor.TYPE_UINT64
+    field = message_type.field.add()
+    field.number = 2
+    field.name = 'nested_message_field'
+    field.label = descriptor.FieldDescriptor.LABEL_REQUIRED
+    field.type = descriptor.FieldDescriptor.TYPE_MESSAGE
+    field.type_name = 'Sub'
+    enum_field = nested_type.field.add()
+    enum_field.number = 2
+    enum_field.name = 'bar_field'
+    enum_field.label = descriptor.FieldDescriptor.LABEL_REQUIRED
+    enum_field.type = descriptor.FieldDescriptor.TYPE_ENUM
+    enum_field.type_name = 'Foo2.Sub.FOO'
+
+    result = descriptor.MakeDescriptor(message_type)
+    self.assertEqual(result.fields[0].cpp_type,
+                     descriptor.FieldDescriptor.CPPTYPE_UINT64)
+    self.assertEqual(result.fields[1].cpp_type,
+                     descriptor.FieldDescriptor.CPPTYPE_MESSAGE)
+    self.assertEqual(result.fields[1].message_type.containing_type,
+                     result)
+    self.assertEqual(result.nested_types[0].fields[0].full_name,
+                     'Foo2.Sub.bar_field')
+    self.assertEqual(result.nested_types[0].fields[0].enum_type,
+                     result.nested_types[0].enum_types[0])
+
   def testMakeDescriptorWithUnsignedIntField(self):
     file_descriptor_proto = descriptor_pb2.FileDescriptorProto()
     file_descriptor_proto.name = 'Foo'
     message_type = file_descriptor_proto.message_type.add()
     message_type.name = file_descriptor_proto.name
+    enum_type = message_type.enum_type.add()
+    enum_type.name = 'FOO'
+    enum_type_val = enum_type.value.add()
+    enum_type_val.name = 'BAR'
+    enum_type_val.number = 3
     field = message_type.field.add()
     field.number = 1
     field.name = 'uint64_field'
     field.label = descriptor.FieldDescriptor.LABEL_REQUIRED
     field.type = descriptor.FieldDescriptor.TYPE_UINT64
+    enum_field = message_type.field.add()
+    enum_field.number = 2
+    enum_field.name = 'bar_field'
+    enum_field.label = descriptor.FieldDescriptor.LABEL_REQUIRED
+    enum_field.type = descriptor.FieldDescriptor.TYPE_ENUM
+    enum_field.type_name = 'Foo.FOO'
+
     result = descriptor.MakeDescriptor(message_type)
     self.assertEqual(result.fields[0].cpp_type,
                      descriptor.FieldDescriptor.CPPTYPE_UINT64)
 
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/encoder.py b/python/google/protobuf/internal/encoder.py
index 777975e8..0a7c0417 100755
--- a/python/google/protobuf/internal/encoder.py
+++ b/python/google/protobuf/internal/encoder.py
@@ -28,6 +28,10 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#PY25 compatible for GAE.
+#
+# Copyright 2009 Google Inc. All Rights Reserved.
+
 """Code for encoding protocol message primitives.
 
 Contains the logic for encoding every logical protocol field type
@@ -67,6 +71,8 @@ sizer rather than when calling them.  In particular:
 __author__ = 'kenton@google.com (Kenton Varda)'
 
 import struct
+import sys  ##PY25
+_PY2 = sys.version_info[0] < 3  ##PY25
 from google.protobuf.internal import wire_format
 
 
@@ -340,7 +346,8 @@ def MessageSetItemSizer(field_number):
 def _VarintEncoder():
   """Return an encoder for a basic varint value (does not include tag)."""
 
-  local_chr = chr
+  local_chr = _PY2 and chr or (lambda x: bytes((x,)))  ##PY25
+##!PY25  local_chr = chr if bytes is str else lambda x: bytes((x,))
   def EncodeVarint(write, value):
     bits = value & 0x7f
     value >>= 7
@@ -357,7 +364,8 @@ def _SignedVarintEncoder():
   """Return an encoder for a basic signed varint value (does not include
   tag)."""
 
-  local_chr = chr
+  local_chr = _PY2 and chr or (lambda x: bytes((x,)))  ##PY25
+##!PY25  local_chr = chr if bytes is str else lambda x: bytes((x,))
   def EncodeSignedVarint(write, value):
     if value < 0:
       value += (1 << 64)
@@ -382,7 +390,8 @@ def _VarintBytes(value):
 
   pieces = []
   _EncodeVarint(pieces.append, value)
-  return "".join(pieces)
+  return "".encode("latin1").join(pieces)  ##PY25
+##!PY25  return b"".join(pieces)
 
 
 def TagBytes(field_number, wire_type):
@@ -520,26 +529,33 @@ def _FloatingPointEncoder(wire_type, format):
       format:  The format string to pass to struct.pack().
   """
 
+  b = _PY2 and (lambda x:x) or (lambda x:x.encode('latin1'))  ##PY25
   value_size = struct.calcsize(format)
   if value_size == 4:
     def EncodeNonFiniteOrRaise(write, value):
       # Remember that the serialized form uses little-endian byte order.
       if value == _POS_INF:
-        write('\x00\x00\x80\x7F')
+        write(b('\x00\x00\x80\x7F'))  ##PY25
+##!PY25        write(b'\x00\x00\x80\x7F')
       elif value == _NEG_INF:
-        write('\x00\x00\x80\xFF')
+        write(b('\x00\x00\x80\xFF'))  ##PY25
+##!PY25        write(b'\x00\x00\x80\xFF')
       elif value != value:           # NaN
-        write('\x00\x00\xC0\x7F')
+        write(b('\x00\x00\xC0\x7F'))  ##PY25
+##!PY25        write(b'\x00\x00\xC0\x7F')
       else:
         raise
   elif value_size == 8:
     def EncodeNonFiniteOrRaise(write, value):
       if value == _POS_INF:
-        write('\x00\x00\x00\x00\x00\x00\xF0\x7F')
+        write(b('\x00\x00\x00\x00\x00\x00\xF0\x7F'))  ##PY25
+##!PY25        write(b'\x00\x00\x00\x00\x00\x00\xF0\x7F')
       elif value == _NEG_INF:
-        write('\x00\x00\x00\x00\x00\x00\xF0\xFF')
+        write(b('\x00\x00\x00\x00\x00\x00\xF0\xFF'))  ##PY25
+##!PY25        write(b'\x00\x00\x00\x00\x00\x00\xF0\xFF')
       elif value != value:                         # NaN
-        write('\x00\x00\x00\x00\x00\x00\xF8\x7F')
+        write(b('\x00\x00\x00\x00\x00\x00\xF8\x7F'))  ##PY25
+##!PY25        write(b'\x00\x00\x00\x00\x00\x00\xF8\x7F')
       else:
         raise
   else:
@@ -615,8 +631,10 @@ DoubleEncoder   = _FloatingPointEncoder(wire_format.WIRETYPE_FIXED64, '<d')
 def BoolEncoder(field_number, is_repeated, is_packed):
   """Returns an encoder for a boolean field."""
 
-  false_byte = chr(0)
-  true_byte = chr(1)
+##!PY25  false_byte = b'\x00'
+##!PY25  true_byte = b'\x01'
+  false_byte = '\x00'.encode('latin1')  ##PY25
+  true_byte = '\x01'.encode('latin1')  ##PY25
   if is_packed:
     tag_bytes = TagBytes(field_number, wire_format.WIRETYPE_LENGTH_DELIMITED)
     local_EncodeVarint = _EncodeVarint
@@ -752,7 +770,8 @@ def MessageSetItemEncoder(field_number):
       }
     }
   """
-  start_bytes = "".join([
+  start_bytes = "".encode("latin1").join([  ##PY25
+##!PY25  start_bytes = b"".join([
       TagBytes(1, wire_format.WIRETYPE_START_GROUP),
       TagBytes(2, wire_format.WIRETYPE_VARINT),
       _VarintBytes(field_number),
diff --git a/python/google/protobuf/internal/factory_test1.proto b/python/google/protobuf/internal/factory_test1.proto
index 9f55e037..03dcb2ca 100644
--- a/python/google/protobuf/internal/factory_test1.proto
+++ b/python/google/protobuf/internal/factory_test1.proto
@@ -52,4 +52,6 @@ message Factory1Message {
   optional NestedFactory1Message nested_factory_1_message = 3;
   optional int32 scalar_value = 4;
   repeated string list_value = 5;
+
+  extensions 1000 to max;
 }
diff --git a/python/google/protobuf/internal/factory_test2.proto b/python/google/protobuf/internal/factory_test2.proto
index d3ce4d7f..a8c68123 100644
--- a/python/google/protobuf/internal/factory_test2.proto
+++ b/python/google/protobuf/internal/factory_test2.proto
@@ -70,8 +70,23 @@ message Factory2Message {
   optional string string_with_default = 18 [default = "hello world"];
   optional bool bool_with_default = 19 [default = false];
   optional Factory2Enum enum_with_default = 20 [default = FACTORY_2_VALUE_1];
+  optional bytes bytes_with_default = 21 [default = "a\373\000c"];
+
+
+  extend Factory1Message {
+    optional string one_more_field = 1001;
+  }
+
+  oneof oneof_field {
+    int32 oneof_int = 22;
+    string oneof_string = 23;
+  }
 }
 
 message LoopMessage {
   optional Factory2Message loop = 1;
 }
+
+extend Factory1Message {
+  optional string another_field = 1002;
+}
diff --git a/python/google/protobuf/internal/generator_test.py b/python/google/protobuf/internal/generator_test.py
index 8343aba1..5818060c 100755
--- a/python/google/protobuf/internal/generator_test.py
+++ b/python/google/protobuf/internal/generator_test.py
@@ -41,20 +41,21 @@ further ensures that we can use Python protocol message objects as we expect.
 
 __author__ = 'robinson@google.com (Will Robinson)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf.internal import test_bad_identifiers_pb2
 from google.protobuf import unittest_custom_options_pb2
 from google.protobuf import unittest_import_pb2
 from google.protobuf import unittest_import_public_pb2
 from google.protobuf import unittest_mset_pb2
-from google.protobuf import unittest_pb2
 from google.protobuf import unittest_no_generic_services_pb2
+from google.protobuf import unittest_pb2
 from google.protobuf import service
+from google.protobuf import symbol_database
 
 MAX_EXTENSION = 536870912
 
 
-class GeneratorTest(unittest.TestCase):
+class GeneratorTest(basetest.TestCase):
 
   def testNestedMessageDescriptor(self):
     field_name = 'optional_nested_message'
@@ -217,6 +218,10 @@ class GeneratorTest(unittest.TestCase):
                      'google/protobuf/unittest.proto')
     self.assertEqual(unittest_pb2.DESCRIPTOR.package, 'protobuf_unittest')
     self.assertFalse(unittest_pb2.DESCRIPTOR.serialized_pb is None)
+    self.assertEqual(unittest_pb2.DESCRIPTOR.dependencies,
+                     [unittest_import_pb2.DESCRIPTOR])
+    self.assertEqual(unittest_import_pb2.DESCRIPTOR.dependencies,
+                     [unittest_import_public_pb2.DESCRIPTOR])
 
   def testNoGenericServices(self):
     self.assertTrue(hasattr(unittest_no_generic_services_pb2, "TestMessage"))
@@ -241,6 +246,18 @@ class GeneratorTest(unittest.TestCase):
         unittest_pb2._TESTALLTYPES_NESTEDMESSAGE.name in
         file_type.message_types_by_name)
 
+  def testEnumTypesByName(self):
+    file_type = unittest_pb2.DESCRIPTOR
+    self.assertEqual(
+        unittest_pb2._FOREIGNENUM,
+        file_type.enum_types_by_name[unittest_pb2._FOREIGNENUM.name])
+
+  def testExtensionsByName(self):
+    file_type = unittest_pb2.DESCRIPTOR
+    self.assertEqual(
+        unittest_pb2.my_extension_string,
+        file_type.extensions_by_name[unittest_pb2.my_extension_string.name])
+
   def testPublicImports(self):
     # Test public imports as embedded message.
     all_type_proto = unittest_pb2.TestAllTypes()
@@ -265,5 +282,62 @@ class GeneratorTest(unittest.TestCase):
     self.assertEqual(message.Extensions[test_bad_identifiers_pb2.service],
                      "qux")
 
+  def testOneof(self):
+    desc = unittest_pb2.TestAllTypes.DESCRIPTOR
+    self.assertEqual(1, len(desc.oneofs))
+    self.assertEqual('oneof_field', desc.oneofs[0].name)
+    self.assertEqual(0, desc.oneofs[0].index)
+    self.assertIs(desc, desc.oneofs[0].containing_type)
+    self.assertIs(desc.oneofs[0], desc.oneofs_by_name['oneof_field'])
+    nested_names = set(['oneof_uint32', 'oneof_nested_message',
+                        'oneof_string', 'oneof_bytes'])
+    self.assertSameElements(
+        nested_names,
+        [field.name for field in desc.oneofs[0].fields])
+    for field_name, field_desc in desc.fields_by_name.iteritems():
+      if field_name in nested_names:
+        self.assertIs(desc.oneofs[0], field_desc.containing_oneof)
+      else:
+        self.assertIsNone(field_desc.containing_oneof)
+
+
+class SymbolDatabaseRegistrationTest(basetest.TestCase):
+  """Checks that messages, enums and files are correctly registered."""
+
+  def testGetSymbol(self):
+    self.assertEquals(
+        unittest_pb2.TestAllTypes, symbol_database.Default().GetSymbol(
+            'protobuf_unittest.TestAllTypes'))
+    self.assertEquals(
+        unittest_pb2.TestAllTypes.NestedMessage,
+        symbol_database.Default().GetSymbol(
+            'protobuf_unittest.TestAllTypes.NestedMessage'))
+    with self.assertRaises(KeyError):
+      symbol_database.Default().GetSymbol('protobuf_unittest.NestedMessage')
+    self.assertEquals(
+        unittest_pb2.TestAllTypes.OptionalGroup,
+        symbol_database.Default().GetSymbol(
+            'protobuf_unittest.TestAllTypes.OptionalGroup'))
+    self.assertEquals(
+        unittest_pb2.TestAllTypes.RepeatedGroup,
+        symbol_database.Default().GetSymbol(
+            'protobuf_unittest.TestAllTypes.RepeatedGroup'))
+
+  def testEnums(self):
+    self.assertEquals(
+        'protobuf_unittest.ForeignEnum',
+        symbol_database.Default().pool.FindEnumTypeByName(
+            'protobuf_unittest.ForeignEnum').full_name)
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes.NestedEnum',
+        symbol_database.Default().pool.FindEnumTypeByName(
+            'protobuf_unittest.TestAllTypes.NestedEnum').full_name)
+
+  def testFindFileByName(self):
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        symbol_database.Default().pool.FindFileByName(
+            'google/protobuf/unittest.proto').name)
+
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/message_factory_cpp2_test.py b/python/google/protobuf/internal/message_factory_cpp2_test.py
new file mode 100644
index 00000000..fb52e1b1
--- /dev/null
+++ b/python/google/protobuf/internal/message_factory_cpp2_test.py
@@ -0,0 +1,56 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Tests for google.protobuf.message_factory."""
+
+import os
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'cpp'
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION'] = '2'
+
+# We must set the implementation version above before the google3 imports.
+# pylint: disable=g-import-not-at-top
+from google.apputils import basetest
+from google.protobuf.internal import api_implementation
+# Run all tests from the original module by putting them in our namespace.
+# pylint: disable=wildcard-import
+from google.protobuf.internal.message_factory_test import *
+
+
+class ConfirmCppApi2Test(basetest.TestCase):
+
+  def testImplementationSetting(self):
+    self.assertEqual('cpp', api_implementation.Type())
+    self.assertEqual(2, api_implementation.Version())
+
+
+if __name__ == '__main__':
+  basetest.main()
diff --git a/python/google/protobuf/internal/message_factory_python_test.py b/python/google/protobuf/internal/message_factory_python_test.py
new file mode 100644
index 00000000..6a2053ff
--- /dev/null
+++ b/python/google/protobuf/internal/message_factory_python_test.py
@@ -0,0 +1,54 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Tests for ..public.message_factory for the pure Python implementation."""
+
+import os
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'python'
+
+# We must set the implementation version above before the google3 imports.
+# pylint: disable=g-import-not-at-top
+from google.apputils import basetest
+from google.protobuf.internal import api_implementation
+# Run all tests from the original module by putting them in our namespace.
+# pylint: disable=wildcard-import
+from google.protobuf.internal.message_factory_test import *
+
+
+class ConfirmPurePythonTest(basetest.TestCase):
+
+  def testImplementationSetting(self):
+    self.assertEqual('python', api_implementation.Type())
+
+
+if __name__ == '__main__':
+  basetest.main()
diff --git a/python/google/protobuf/internal/message_factory_test.py b/python/google/protobuf/internal/message_factory_test.py
index 0bc9be99..c53d77bf 100644
--- a/python/google/protobuf/internal/message_factory_test.py
+++ b/python/google/protobuf/internal/message_factory_test.py
@@ -34,7 +34,7 @@
 
 __author__ = 'matthewtoia@google.com (Matt Toia)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import descriptor_pb2
 from google.protobuf.internal import factory_test1_pb2
 from google.protobuf.internal import factory_test2_pb2
@@ -43,7 +43,7 @@ from google.protobuf import descriptor_pool
 from google.protobuf import message_factory
 
 
-class MessageFactoryTest(unittest.TestCase):
+class MessageFactoryTest(basetest.TestCase):
 
   def setUp(self):
     self.factory_test1_fd = descriptor_pb2.FileDescriptorProto.FromString(
@@ -61,8 +61,8 @@ class MessageFactoryTest(unittest.TestCase):
     msg.factory_1_message.nested_factory_1_message.value = (
         'nested message value')
     msg.factory_1_message.scalar_value = 22
-    msg.factory_1_message.list_value.extend(['one', 'two', 'three'])
-    msg.factory_1_message.list_value.append('four')
+    msg.factory_1_message.list_value.extend([u'one', u'two', u'three'])
+    msg.factory_1_message.list_value.append(u'four')
     msg.factory_1_enum = 1
     msg.nested_factory_1_enum = 0
     msg.nested_factory_1_message.value = 'nested message value'
@@ -70,8 +70,8 @@ class MessageFactoryTest(unittest.TestCase):
     msg.circular_message.circular_message.mandatory = 2
     msg.circular_message.scalar_value = 'one deep'
     msg.scalar_value = 'zero deep'
-    msg.list_value.extend(['four', 'three', 'two'])
-    msg.list_value.append('one')
+    msg.list_value.extend([u'four', u'three', u'two'])
+    msg.list_value.append(u'one')
     msg.grouped.add()
     msg.grouped[0].part_1 = 'hello'
     msg.grouped[0].part_2 = 'world'
@@ -92,22 +92,40 @@ class MessageFactoryTest(unittest.TestCase):
     db.Add(self.factory_test2_fd)
     factory = message_factory.MessageFactory()
     cls = factory.GetPrototype(pool.FindMessageTypeByName(
-        'net.proto2.python.internal.Factory2Message'))
+        'google.protobuf.python.internal.Factory2Message'))
     self.assertIsNot(cls, factory_test2_pb2.Factory2Message)
     self._ExerciseDynamicClass(cls)
     cls2 = factory.GetPrototype(pool.FindMessageTypeByName(
-        'net.proto2.python.internal.Factory2Message'))
+        'google.protobuf.python.internal.Factory2Message'))
     self.assertIs(cls, cls2)
 
   def testGetMessages(self):
-    messages = message_factory.GetMessages([self.factory_test2_fd,
-                                            self.factory_test1_fd])
-    self.assertContainsSubset(
-        ['net.proto2.python.internal.Factory2Message',
-         'net.proto2.python.internal.Factory1Message'],
-        messages.keys())
-    self._ExerciseDynamicClass(
-        messages['net.proto2.python.internal.Factory2Message'])
+    # performed twice because multiple calls with the same input must be allowed
+    for _ in range(2):
+      messages = message_factory.GetMessages([self.factory_test2_fd,
+                                              self.factory_test1_fd])
+      self.assertContainsSubset(
+          ['google.protobuf.python.internal.Factory2Message',
+           'google.protobuf.python.internal.Factory1Message'],
+          messages.keys())
+      self._ExerciseDynamicClass(
+          messages['google.protobuf.python.internal.Factory2Message'])
+      self.assertContainsSubset(
+          ['google.protobuf.python.internal.Factory2Message.one_more_field',
+           'google.protobuf.python.internal.another_field'],
+          (messages['google.protobuf.python.internal.Factory1Message']
+           ._extensions_by_name.keys()))
+      factory_msg1 = messages['google.protobuf.python.internal.Factory1Message']
+      msg1 = messages['google.protobuf.python.internal.Factory1Message']()
+      ext1 = factory_msg1._extensions_by_name[
+          'google.protobuf.python.internal.Factory2Message.one_more_field']
+      ext2 = factory_msg1._extensions_by_name[
+          'google.protobuf.python.internal.another_field']
+      msg1.Extensions[ext1] = 'test1'
+      msg1.Extensions[ext2] = 'test2'
+      self.assertEquals('test1', msg1.Extensions[ext1])
+      self.assertEquals('test2', msg1.Extensions[ext2])
+
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/message_cpp_test.py b/python/google/protobuf/internal/message_python_test.py
index 0d84b320..baf15044 100644
--- a/python/google/protobuf/internal/message_cpp_test.py
+++ b/python/google/protobuf/internal/message_python_test.py
@@ -30,16 +30,25 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-"""Tests for google.protobuf.internal.message_cpp."""
-
-__author__ = 'shahms@google.com (Shahms King)'
+"""Tests for ..public.message for the pure Python implementation."""
 
 import os
-os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'cpp'
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'python'
 
-import unittest
+# We must set the implementation version above before the google3 imports.
+# pylint: disable=g-import-not-at-top
+from google.apputils import basetest
+from google.protobuf.internal import api_implementation
+# Run all tests from the original module by putting them in our namespace.
+# pylint: disable=wildcard-import
 from google.protobuf.internal.message_test import *
 
 
+class ConfirmPurePythonTest(basetest.TestCase):
+
+  def testImplementationSetting(self):
+    self.assertEqual('python', api_implementation.Type())
+
+
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/message_test.py b/python/google/protobuf/internal/message_test.py
index 53e9d507..f4c4ae00 100755
--- a/python/google/protobuf/internal/message_test.py
+++ b/python/google/protobuf/internal/message_test.py
@@ -47,9 +47,9 @@ import copy
 import math
 import operator
 import pickle
+import sys
 
-import unittest
-from google.protobuf import unittest_import_pb2
+from google.apputils import basetest
 from google.protobuf import unittest_pb2
 from google.protobuf.internal import api_implementation
 from google.protobuf.internal import test_util
@@ -68,10 +68,23 @@ def IsPosInf(val):
 def IsNegInf(val):
   return isinf(val) and (val < 0)
 
-class MessageTest(unittest.TestCase):
+
+class MessageTest(basetest.TestCase):
+
+  def testBadUtf8String(self):
+    if api_implementation.Type() != 'python':
+      self.skipTest("Skipping testBadUtf8String, currently only the python "
+                    "api implementation raises UnicodeDecodeError when a "
+                    "string field contains bad utf-8.")
+    bad_utf8_data = test_util.GoldenFileData('bad_utf8_string')
+    with self.assertRaises(UnicodeDecodeError) as context:
+      unittest_pb2.TestAllTypes.FromString(bad_utf8_data)
+    self.assertIn('field: protobuf_unittest.TestAllTypes.optional_string',
+                  str(context.exception))
 
   def testGoldenMessage(self):
-    golden_data = test_util.GoldenFile('golden_message').read()
+    golden_data = test_util.GoldenFileData(
+        'golden_message_oneof_implemented')
     golden_message = unittest_pb2.TestAllTypes()
     golden_message.ParseFromString(golden_data)
     test_util.ExpectAllFieldsSet(self, golden_message)
@@ -80,7 +93,7 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_copy.SerializeToString())
 
   def testGoldenExtensions(self):
-    golden_data = test_util.GoldenFile('golden_message').read()
+    golden_data = test_util.GoldenFileData('golden_message')
     golden_message = unittest_pb2.TestAllExtensions()
     golden_message.ParseFromString(golden_data)
     all_set = unittest_pb2.TestAllExtensions()
@@ -91,7 +104,7 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_copy.SerializeToString())
 
   def testGoldenPackedMessage(self):
-    golden_data = test_util.GoldenFile('golden_packed_fields_message').read()
+    golden_data = test_util.GoldenFileData('golden_packed_fields_message')
     golden_message = unittest_pb2.TestPackedTypes()
     golden_message.ParseFromString(golden_data)
     all_set = unittest_pb2.TestPackedTypes()
@@ -102,7 +115,7 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_copy.SerializeToString())
 
   def testGoldenPackedExtensions(self):
-    golden_data = test_util.GoldenFile('golden_packed_fields_message').read()
+    golden_data = test_util.GoldenFileData('golden_packed_fields_message')
     golden_message = unittest_pb2.TestPackedExtensions()
     golden_message.ParseFromString(golden_data)
     all_set = unittest_pb2.TestPackedExtensions()
@@ -113,7 +126,7 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_copy.SerializeToString())
 
   def testPickleSupport(self):
-    golden_data = test_util.GoldenFile('golden_message').read()
+    golden_data = test_util.GoldenFileData('golden_message')
     golden_message = unittest_pb2.TestAllTypes()
     golden_message.ParseFromString(golden_data)
     pickled_message = pickle.dumps(golden_message)
@@ -121,6 +134,7 @@ class MessageTest(unittest.TestCase):
     unpickled_message = pickle.loads(pickled_message)
     self.assertEquals(unpickled_message, golden_message)
 
+
   def testPickleIncompleteProto(self):
     golden_message = unittest_pb2.TestRequired(a=1)
     pickled_message = pickle.dumps(golden_message)
@@ -132,10 +146,10 @@ class MessageTest(unittest.TestCase):
     self.assertRaises(message.EncodeError, unpickled_message.SerializeToString)
 
   def testPositiveInfinity(self):
-    golden_data = ('\x5D\x00\x00\x80\x7F'
-                   '\x61\x00\x00\x00\x00\x00\x00\xF0\x7F'
-                   '\xCD\x02\x00\x00\x80\x7F'
-                   '\xD1\x02\x00\x00\x00\x00\x00\x00\xF0\x7F')
+    golden_data = (b'\x5D\x00\x00\x80\x7F'
+                   b'\x61\x00\x00\x00\x00\x00\x00\xF0\x7F'
+                   b'\xCD\x02\x00\x00\x80\x7F'
+                   b'\xD1\x02\x00\x00\x00\x00\x00\x00\xF0\x7F')
     golden_message = unittest_pb2.TestAllTypes()
     golden_message.ParseFromString(golden_data)
     self.assertTrue(IsPosInf(golden_message.optional_float))
@@ -145,10 +159,10 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_message.SerializeToString())
 
   def testNegativeInfinity(self):
-    golden_data = ('\x5D\x00\x00\x80\xFF'
-                   '\x61\x00\x00\x00\x00\x00\x00\xF0\xFF'
-                   '\xCD\x02\x00\x00\x80\xFF'
-                   '\xD1\x02\x00\x00\x00\x00\x00\x00\xF0\xFF')
+    golden_data = (b'\x5D\x00\x00\x80\xFF'
+                   b'\x61\x00\x00\x00\x00\x00\x00\xF0\xFF'
+                   b'\xCD\x02\x00\x00\x80\xFF'
+                   b'\xD1\x02\x00\x00\x00\x00\x00\x00\xF0\xFF')
     golden_message = unittest_pb2.TestAllTypes()
     golden_message.ParseFromString(golden_data)
     self.assertTrue(IsNegInf(golden_message.optional_float))
@@ -158,10 +172,10 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_message.SerializeToString())
 
   def testNotANumber(self):
-    golden_data = ('\x5D\x00\x00\xC0\x7F'
-                   '\x61\x00\x00\x00\x00\x00\x00\xF8\x7F'
-                   '\xCD\x02\x00\x00\xC0\x7F'
-                   '\xD1\x02\x00\x00\x00\x00\x00\x00\xF8\x7F')
+    golden_data = (b'\x5D\x00\x00\xC0\x7F'
+                   b'\x61\x00\x00\x00\x00\x00\x00\xF8\x7F'
+                   b'\xCD\x02\x00\x00\xC0\x7F'
+                   b'\xD1\x02\x00\x00\x00\x00\x00\x00\xF8\x7F')
     golden_message = unittest_pb2.TestAllTypes()
     golden_message.ParseFromString(golden_data)
     self.assertTrue(isnan(golden_message.optional_float))
@@ -182,8 +196,8 @@ class MessageTest(unittest.TestCase):
     self.assertTrue(isnan(message.repeated_double[0]))
 
   def testPositiveInfinityPacked(self):
-    golden_data = ('\xA2\x06\x04\x00\x00\x80\x7F'
-                   '\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF0\x7F')
+    golden_data = (b'\xA2\x06\x04\x00\x00\x80\x7F'
+                   b'\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF0\x7F')
     golden_message = unittest_pb2.TestPackedTypes()
     golden_message.ParseFromString(golden_data)
     self.assertTrue(IsPosInf(golden_message.packed_float[0]))
@@ -191,8 +205,8 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_message.SerializeToString())
 
   def testNegativeInfinityPacked(self):
-    golden_data = ('\xA2\x06\x04\x00\x00\x80\xFF'
-                   '\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF0\xFF')
+    golden_data = (b'\xA2\x06\x04\x00\x00\x80\xFF'
+                   b'\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF0\xFF')
     golden_message = unittest_pb2.TestPackedTypes()
     golden_message.ParseFromString(golden_data)
     self.assertTrue(IsNegInf(golden_message.packed_float[0]))
@@ -200,8 +214,8 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(golden_data, golden_message.SerializeToString())
 
   def testNotANumberPacked(self):
-    golden_data = ('\xA2\x06\x04\x00\x00\xC0\x7F'
-                   '\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF8\x7F')
+    golden_data = (b'\xA2\x06\x04\x00\x00\xC0\x7F'
+                   b'\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF8\x7F')
     golden_message = unittest_pb2.TestPackedTypes()
     golden_message.ParseFromString(golden_data)
     self.assertTrue(isnan(golden_message.packed_float[0]))
@@ -303,6 +317,26 @@ class MessageTest(unittest.TestCase):
     message.ParseFromString(message.SerializeToString())
     self.assertTrue(message.optional_double == -kMostNegExponentOneSigBit)
 
+  def testFloatPrinting(self):
+    message = unittest_pb2.TestAllTypes()
+    message.optional_float = 2.0
+    self.assertEqual(str(message), 'optional_float: 2.0\n')
+
+  def testHighPrecisionFloatPrinting(self):
+    message = unittest_pb2.TestAllTypes()
+    message.optional_double = 0.12345678912345678
+    if sys.version_info.major >= 3:
+      self.assertEqual(str(message), 'optional_double: 0.12345678912345678\n')
+    else:
+      self.assertEqual(str(message), 'optional_double: 0.123456789123\n')
+
+  def testUnknownFieldPrinting(self):
+    populated = unittest_pb2.TestAllTypes()
+    test_util.SetAllNonLazyFields(populated)
+    empty = unittest_pb2.TestEmptyMessage()
+    empty.ParseFromString(populated.SerializeToString())
+    self.assertEqual(str(empty), '')
+
   def testSortingRepeatedScalarFieldsDefaultComparator(self):
     """Check some different types with the default comparator."""
     message = unittest_pb2.TestAllTypes()
@@ -332,13 +366,13 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(message.repeated_string[1], 'b')
     self.assertEqual(message.repeated_string[2], 'c')
 
-    message.repeated_bytes.append('a')
-    message.repeated_bytes.append('c')
-    message.repeated_bytes.append('b')
+    message.repeated_bytes.append(b'a')
+    message.repeated_bytes.append(b'c')
+    message.repeated_bytes.append(b'b')
     message.repeated_bytes.sort()
-    self.assertEqual(message.repeated_bytes[0], 'a')
-    self.assertEqual(message.repeated_bytes[1], 'b')
-    self.assertEqual(message.repeated_bytes[2], 'c')
+    self.assertEqual(message.repeated_bytes[0], b'a')
+    self.assertEqual(message.repeated_bytes[1], b'b')
+    self.assertEqual(message.repeated_bytes[2], b'c')
 
   def testSortingRepeatedScalarFieldsCustomComparator(self):
     """Check some different types with custom comparator."""
@@ -347,7 +381,7 @@ class MessageTest(unittest.TestCase):
     message.repeated_int32.append(-3)
     message.repeated_int32.append(-2)
     message.repeated_int32.append(-1)
-    message.repeated_int32.sort(lambda x,y: cmp(abs(x), abs(y)))
+    message.repeated_int32.sort(key=abs)
     self.assertEqual(message.repeated_int32[0], -1)
     self.assertEqual(message.repeated_int32[1], -2)
     self.assertEqual(message.repeated_int32[2], -3)
@@ -355,7 +389,7 @@ class MessageTest(unittest.TestCase):
     message.repeated_string.append('aaa')
     message.repeated_string.append('bb')
     message.repeated_string.append('c')
-    message.repeated_string.sort(lambda x,y: cmp(len(x), len(y)))
+    message.repeated_string.sort(key=len)
     self.assertEqual(message.repeated_string[0], 'c')
     self.assertEqual(message.repeated_string[1], 'bb')
     self.assertEqual(message.repeated_string[2], 'aaa')
@@ -370,7 +404,7 @@ class MessageTest(unittest.TestCase):
     message.repeated_nested_message.add().bb = 6
     message.repeated_nested_message.add().bb = 5
     message.repeated_nested_message.add().bb = 4
-    message.repeated_nested_message.sort(lambda x,y: cmp(x.bb, y.bb))
+    message.repeated_nested_message.sort(key=operator.attrgetter('bb'))
     self.assertEqual(message.repeated_nested_message[0].bb, 1)
     self.assertEqual(message.repeated_nested_message[1].bb, 2)
     self.assertEqual(message.repeated_nested_message[2].bb, 3)
@@ -396,6 +430,7 @@ class MessageTest(unittest.TestCase):
     message.repeated_nested_message.sort(key=get_bb, reverse=True)
     self.assertEqual([k.bb for k in message.repeated_nested_message],
                      [6, 5, 4, 3, 2, 1])
+    if sys.version_info.major >= 3: return  # No cmp sorting in PY3.
     message.repeated_nested_message.sort(sort_function=cmp_bb)
     self.assertEqual([k.bb for k in message.repeated_nested_message],
                      [1, 2, 3, 4, 5, 6])
@@ -407,7 +442,6 @@ class MessageTest(unittest.TestCase):
     """Check sorting a scalar field using list.sort() arguments."""
     message = unittest_pb2.TestAllTypes()
 
-    abs_cmp = lambda a, b: cmp(abs(a), abs(b))
     message.repeated_int32.append(-3)
     message.repeated_int32.append(-2)
     message.repeated_int32.append(-1)
@@ -415,12 +449,13 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(list(message.repeated_int32), [-1, -2, -3])
     message.repeated_int32.sort(key=abs, reverse=True)
     self.assertEqual(list(message.repeated_int32), [-3, -2, -1])
-    message.repeated_int32.sort(sort_function=abs_cmp)
-    self.assertEqual(list(message.repeated_int32), [-1, -2, -3])
-    message.repeated_int32.sort(cmp=abs_cmp, reverse=True)
-    self.assertEqual(list(message.repeated_int32), [-3, -2, -1])
+    if sys.version_info.major < 3:  # No cmp sorting in PY3.
+      abs_cmp = lambda a, b: cmp(abs(a), abs(b))
+      message.repeated_int32.sort(sort_function=abs_cmp)
+      self.assertEqual(list(message.repeated_int32), [-1, -2, -3])
+      message.repeated_int32.sort(cmp=abs_cmp, reverse=True)
+      self.assertEqual(list(message.repeated_int32), [-3, -2, -1])
 
-    len_cmp = lambda a, b: cmp(len(a), len(b))
     message.repeated_string.append('aaa')
     message.repeated_string.append('bb')
     message.repeated_string.append('c')
@@ -428,10 +463,47 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(list(message.repeated_string), ['c', 'bb', 'aaa'])
     message.repeated_string.sort(key=len, reverse=True)
     self.assertEqual(list(message.repeated_string), ['aaa', 'bb', 'c'])
-    message.repeated_string.sort(sort_function=len_cmp)
-    self.assertEqual(list(message.repeated_string), ['c', 'bb', 'aaa'])
-    message.repeated_string.sort(cmp=len_cmp, reverse=True)
-    self.assertEqual(list(message.repeated_string), ['aaa', 'bb', 'c'])
+    if sys.version_info.major < 3:  # No cmp sorting in PY3.
+      len_cmp = lambda a, b: cmp(len(a), len(b))
+      message.repeated_string.sort(sort_function=len_cmp)
+      self.assertEqual(list(message.repeated_string), ['c', 'bb', 'aaa'])
+      message.repeated_string.sort(cmp=len_cmp, reverse=True)
+      self.assertEqual(list(message.repeated_string), ['aaa', 'bb', 'c'])
+
+  def testRepeatedFieldsComparable(self):
+    m1 = unittest_pb2.TestAllTypes()
+    m2 = unittest_pb2.TestAllTypes()
+    m1.repeated_int32.append(0)
+    m1.repeated_int32.append(1)
+    m1.repeated_int32.append(2)
+    m2.repeated_int32.append(0)
+    m2.repeated_int32.append(1)
+    m2.repeated_int32.append(2)
+    m1.repeated_nested_message.add().bb = 1
+    m1.repeated_nested_message.add().bb = 2
+    m1.repeated_nested_message.add().bb = 3
+    m2.repeated_nested_message.add().bb = 1
+    m2.repeated_nested_message.add().bb = 2
+    m2.repeated_nested_message.add().bb = 3
+
+    if sys.version_info.major >= 3: return  # No cmp() in PY3.
+
+    # These comparisons should not raise errors.
+    _ = m1 < m2
+    _ = m1.repeated_nested_message < m2.repeated_nested_message
+
+    # Make sure cmp always works. If it wasn't defined, these would be
+    # id() comparisons and would all fail.
+    self.assertEqual(cmp(m1, m2), 0)
+    self.assertEqual(cmp(m1.repeated_int32, m2.repeated_int32), 0)
+    self.assertEqual(cmp(m1.repeated_int32, [0, 1, 2]), 0)
+    self.assertEqual(cmp(m1.repeated_nested_message,
+                         m2.repeated_nested_message), 0)
+    with self.assertRaises(TypeError):
+      # Can't compare repeated composite containers to lists.
+      cmp(m1.repeated_nested_message, m2.repeated_nested_message[:])
+
+    # TODO(anuraag): Implement extensiondict comparison in C++ and then add test
 
   def testParsingMerge(self):
     """Check the merge behavior when a required or optional field appears
@@ -482,6 +554,87 @@ class MessageTest(unittest.TestCase):
     self.assertEqual(len(parsing_merge.Extensions[
         unittest_pb2.TestParsingMerge.repeated_ext]), 3)
 
+  def ensureNestedMessageExists(self, msg, attribute):
+    """Make sure that a nested message object exists.
+
+    As soon as a nested message attribute is accessed, it will be present in the
+    _fields dict, without being marked as actually being set.
+    """
+    getattr(msg, attribute)
+    self.assertFalse(msg.HasField(attribute))
+
+  def testOneofGetCaseNonexistingField(self):
+    m = unittest_pb2.TestAllTypes()
+    self.assertRaises(ValueError, m.WhichOneof, 'no_such_oneof_field')
+
+  def testOneofSemantics(self):
+    m = unittest_pb2.TestAllTypes()
+    self.assertIs(None, m.WhichOneof('oneof_field'))
+
+    m.oneof_uint32 = 11
+    self.assertEqual('oneof_uint32', m.WhichOneof('oneof_field'))
+    self.assertTrue(m.HasField('oneof_uint32'))
+
+    m.oneof_string = u'foo'
+    self.assertEqual('oneof_string', m.WhichOneof('oneof_field'))
+    self.assertFalse(m.HasField('oneof_uint32'))
+    self.assertTrue(m.HasField('oneof_string'))
+
+    m.oneof_nested_message.bb = 11
+    self.assertEqual('oneof_nested_message', m.WhichOneof('oneof_field'))
+    self.assertFalse(m.HasField('oneof_string'))
+    self.assertTrue(m.HasField('oneof_nested_message'))
+
+    m.oneof_bytes = b'bb'
+    self.assertEqual('oneof_bytes', m.WhichOneof('oneof_field'))
+    self.assertFalse(m.HasField('oneof_nested_message'))
+    self.assertTrue(m.HasField('oneof_bytes'))
+
+  def testOneofCompositeFieldReadAccess(self):
+    m = unittest_pb2.TestAllTypes()
+    m.oneof_uint32 = 11
+
+    self.ensureNestedMessageExists(m, 'oneof_nested_message')
+    self.assertEqual('oneof_uint32', m.WhichOneof('oneof_field'))
+    self.assertEqual(11, m.oneof_uint32)
+
+  def testOneofHasField(self):
+    m = unittest_pb2.TestAllTypes()
+    self.assertFalse(m.HasField('oneof_field'))
+    m.oneof_uint32 = 11
+    self.assertTrue(m.HasField('oneof_field'))
+    m.oneof_bytes = b'bb'
+    self.assertTrue(m.HasField('oneof_field'))
+    m.ClearField('oneof_bytes')
+    self.assertFalse(m.HasField('oneof_field'))
+
+  def testOneofClearField(self):
+    m = unittest_pb2.TestAllTypes()
+    m.oneof_uint32 = 11
+    m.ClearField('oneof_field')
+    self.assertFalse(m.HasField('oneof_field'))
+    self.assertFalse(m.HasField('oneof_uint32'))
+    self.assertIs(None, m.WhichOneof('oneof_field'))
+
+  def testOneofClearSetField(self):
+    m = unittest_pb2.TestAllTypes()
+    m.oneof_uint32 = 11
+    m.ClearField('oneof_uint32')
+    self.assertFalse(m.HasField('oneof_field'))
+    self.assertFalse(m.HasField('oneof_uint32'))
+    self.assertIs(None, m.WhichOneof('oneof_field'))
+
+  def testOneofClearUnsetField(self):
+    m = unittest_pb2.TestAllTypes()
+    m.oneof_uint32 = 11
+    self.ensureNestedMessageExists(m, 'oneof_nested_message')
+    m.ClearField('oneof_nested_message')
+    self.assertEqual(11, m.oneof_uint32)
+    self.assertTrue(m.HasField('oneof_field'))
+    self.assertTrue(m.HasField('oneof_uint32'))
+    self.assertEqual('oneof_uint32', m.WhichOneof('oneof_field'))
+
+
 
   def testSortEmptyRepeatedCompositeContainer(self):
     """Exercise a scenario that has led to segfaults in the past.
@@ -489,6 +642,35 @@ class MessageTest(unittest.TestCase):
     m = unittest_pb2.TestAllTypes()
     m.repeated_nested_message.sort()
 
+  def testHasFieldOnRepeatedField(self):
+    """Using HasField on a repeated field should raise an exception.
+    """
+    m = unittest_pb2.TestAllTypes()
+    with self.assertRaises(ValueError) as _:
+      m.HasField('repeated_int32')
+
+
+class ValidTypeNamesTest(basetest.TestCase):
+
+  def assertImportFromName(self, msg, base_name):
+    # Parse <type 'module.class_name'> to extra 'some.name' as a string.
+    tp_name = str(type(msg)).split("'")[1]
+    valid_names = ('Repeated%sContainer' % base_name,
+                   'Repeated%sFieldContainer' % base_name)
+    self.assertTrue(any(tp_name.endswith(v) for v in valid_names),
+                    '%r does end with any of %r' % (tp_name, valid_names))
+
+    parts = tp_name.split('.')
+    class_name = parts[-1]
+    module_name = '.'.join(parts[:-1])
+    __import__(module_name, fromlist=[class_name])
+
+  def testTypeNamesCanBeImported(self):
+    # If import doesn't work, pickling won't work either.
+    pb = unittest_pb2.TestAllTypes()
+    self.assertImportFromName(pb.repeated_int32, 'Scalar')
+    self.assertImportFromName(pb.repeated_nested_message, 'Composite')
+
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/missing_enum_values.proto b/python/google/protobuf/internal/missing_enum_values.proto
new file mode 100644
index 00000000..c9ae58b6
--- /dev/null
+++ b/python/google/protobuf/internal/missing_enum_values.proto
@@ -0,0 +1,50 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package google.protobuf.python.internal;
+
+message TestEnumValues {
+  enum NestedEnum {
+    ZERO = 0;
+    ONE = 1;
+  }
+  optional NestedEnum optional_nested_enum = 1;
+  repeated NestedEnum repeated_nested_enum = 2;
+  repeated NestedEnum packed_nested_enum = 3 [packed = true];
+}
+
+message TestMissingEnumValues {
+  enum NestedEnum {
+    TWO = 2;
+  }
+  optional NestedEnum optional_nested_enum = 1;
+  repeated NestedEnum repeated_nested_enum = 2;
+  repeated NestedEnum packed_nested_enum = 3 [packed = true];
+}
diff --git a/python/google/protobuf/internal/python_message.py b/python/google/protobuf/internal/python_message.py
index 4bea57ac..9ee352d6 100755
--- a/python/google/protobuf/internal/python_message.py
+++ b/python/google/protobuf/internal/python_message.py
@@ -28,6 +28,10 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+# Keep it Python2.5 compatible for GAE.
+#
+# Copyright 2007 Google Inc. All Rights Reserved.
+#
 # This code is meant to work on Python 2.4 and above only.
 #
 # TODO(robinson): Helpers for verbose, common checks like seeing if a
@@ -50,11 +54,16 @@ this file*.
 
 __author__ = 'robinson@google.com (Will Robinson)'
 
-try:
-  from cStringIO import StringIO
-except ImportError:
-  from StringIO import StringIO
-import copy_reg
+import sys
+if sys.version_info[0] < 3:
+  try:
+    from cStringIO import StringIO as BytesIO
+  except ImportError:
+    from StringIO import StringIO as BytesIO
+  import copy_reg as copyreg
+else:
+  from io import BytesIO
+  import copyreg
 import struct
 import weakref
 
@@ -98,8 +107,8 @@ def InitMessage(descriptor, cls):
   _AddPropertiesForExtensions(descriptor, cls)
   _AddStaticMethods(cls)
   _AddMessageMethods(descriptor, cls)
-  _AddPrivateHelperMethods(cls)
-  copy_reg.pickle(cls, lambda obj: (cls, (), obj.__getstate__()))
+  _AddPrivateHelperMethods(descriptor, cls)
+  copyreg.pickle(cls, lambda obj: (cls, (), obj.__getstate__()))
 
 
 # Stateless helpers for GeneratedProtocolMessageType below.
@@ -176,7 +185,8 @@ def _AddSlots(message_descriptor, dictionary):
                              '_is_present_in_parent',
                              '_listener',
                              '_listener_for_children',
-                             '__weakref__']
+                             '__weakref__',
+                             '_oneofs']
 
 
 def _IsMessageSetExtension(field):
@@ -272,7 +282,7 @@ def _DefaultValueConstructorForField(field):
             message._listener_for_children, field.message_type)
       return MakeRepeatedMessageDefault
     else:
-      type_checker = type_checkers.GetTypeChecker(field.cpp_type, field.type)
+      type_checker = type_checkers.GetTypeChecker(field)
       def MakeRepeatedScalarDefault(message):
         return containers.RepeatedScalarFieldContainer(
             message._listener_for_children, type_checker)
@@ -301,6 +311,10 @@ def _AddInitMethod(message_descriptor, cls):
     self._cached_byte_size = 0
     self._cached_byte_size_dirty = len(kwargs) > 0
     self._fields = {}
+    # Contains a mapping from oneof field descriptors to the descriptor
+    # of the currently set field in that oneof field.
+    self._oneofs = {}
+
     # _unknown_fields is () when empty for efficiency, and will be turned into
     # a list if fields are added.
     self._unknown_fields = ()
@@ -440,7 +454,7 @@ def _AddPropertiesForNonRepeatedScalarField(field, cls):
   """
   proto_field_name = field.name
   property_name = _PropertyName(proto_field_name)
-  type_checker = type_checkers.GetTypeChecker(field.cpp_type, field.type)
+  type_checker = type_checkers.GetTypeChecker(field)
   default_value = field.default_value
   valid_values = set()
 
@@ -450,14 +464,21 @@ def _AddPropertiesForNonRepeatedScalarField(field, cls):
     return self._fields.get(field, default_value)
   getter.__module__ = None
   getter.__doc__ = 'Getter for %s.' % proto_field_name
-  def setter(self, new_value):
-    type_checker.CheckValue(new_value)
-    self._fields[field] = new_value
+  def field_setter(self, new_value):
+    # pylint: disable=protected-access
+    self._fields[field] = type_checker.CheckValue(new_value)
     # Check _cached_byte_size_dirty inline to improve performance, since scalar
     # setters are called frequently.
     if not self._cached_byte_size_dirty:
       self._Modified()
 
+  if field.containing_oneof is not None:
+    def setter(self, new_value):
+      field_setter(self, new_value)
+      self._UpdateOneofState(field)
+  else:
+    setter = field_setter
+
   setter.__module__ = None
   setter.__doc__ = 'Setter for %s.' % proto_field_name
 
@@ -493,7 +514,10 @@ def _AddPropertiesForNonRepeatedCompositeField(field, cls):
     if field_value is None:
       # Construct a new object to represent this field.
       field_value = message_type._concrete_class()  # use field.message_type?
-      field_value._SetListener(self._listener_for_children)
+      field_value._SetListener(
+          _OneofListener(self, field)
+          if field.containing_oneof is not None
+          else self._listener_for_children)
 
       # Atomically check if another thread has preempted us and, if not, swap
       # in the new object we just created.  If someone has preempted us, we
@@ -589,6 +613,9 @@ def _AddHasFieldMethod(message_descriptor, cls):
   for field in message_descriptor.fields:
     if field.label != _FieldDescriptor.LABEL_REPEATED:
       singular_fields[field.name] = field
+  # Fields inside oneofs are never repeated (enforced by the compiler).
+  for field in message_descriptor.oneofs:
+    singular_fields[field.name] = field
 
   def HasField(self, field_name):
     try:
@@ -597,11 +624,18 @@ def _AddHasFieldMethod(message_descriptor, cls):
       raise ValueError(
           'Protocol message has no singular "%s" field.' % field_name)
 
-    if field.cpp_type == _FieldDescriptor.CPPTYPE_MESSAGE:
-      value = self._fields.get(field)
-      return value is not None and value._is_present_in_parent
+    if isinstance(field, descriptor_mod.OneofDescriptor):
+      try:
+        return HasField(self, self._oneofs[field].name)
+      except KeyError:
+        return False
     else:
-      return field in self._fields
+      if field.cpp_type == _FieldDescriptor.CPPTYPE_MESSAGE:
+        value = self._fields.get(field)
+        return value is not None and value._is_present_in_parent
+      else:
+        return field in self._fields
+
   cls.HasField = HasField
 
 
@@ -611,7 +645,14 @@ def _AddClearFieldMethod(message_descriptor, cls):
     try:
       field = message_descriptor.fields_by_name[field_name]
     except KeyError:
-      raise ValueError('Protocol message has no "%s" field.' % field_name)
+      try:
+        field = message_descriptor.oneofs_by_name[field_name]
+        if field in self._oneofs:
+          field = self._oneofs[field]
+        else:
+          return
+      except KeyError:
+        raise ValueError('Protocol message has no "%s" field.' % field_name)
 
     if field in self._fields:
       # Note:  If the field is a sub-message, its listener will still point
@@ -619,6 +660,9 @@ def _AddClearFieldMethod(message_descriptor, cls):
       #   will call _Modified() and invalidate our byte size.  Big deal.
       del self._fields[field]
 
+      if self._oneofs.get(field.containing_oneof, None) is field:
+        del self._oneofs[field.containing_oneof]
+
     # Always call _Modified() -- even if nothing was changed, this is
     # a mutating method, and thus calling it should cause the field to become
     # present in the parent message.
@@ -773,7 +817,7 @@ def _AddSerializePartialToStringMethod(message_descriptor, cls):
   """Helper for _AddMessageMethods()."""
 
   def SerializePartialToString(self):
-    out = StringIO()
+    out = BytesIO()
     self._InternalSerialize(out.write)
     return out.getvalue()
   cls.SerializePartialToString = SerializePartialToString
@@ -796,7 +840,8 @@ def _AddMergeFromStringMethod(message_descriptor, cls):
         # The only reason _InternalParse would return early is if it
         # encountered an end-group tag.
         raise message_mod.DecodeError('Unexpected end-group tag.')
-    except IndexError:
+    except (IndexError, TypeError):
+      # Now ord(buf[p:p+1]) == ord('') gets TypeError.
       raise message_mod.DecodeError('Truncated message.')
     except struct.error, e:
       raise message_mod.DecodeError(e)
@@ -857,7 +902,7 @@ def _AddIsInitializedMethod(message_descriptor, cls):
           errors.extend(self.FindInitializationErrors())
         return False
 
-    for field, value in self._fields.iteritems():
+    for field, value in list(self._fields.items()):  # dict can change size!
       if field.cpp_type == _FieldDescriptor.CPPTYPE_MESSAGE:
         if field.label == _FieldDescriptor.LABEL_REPEATED:
           for element in value:
@@ -953,6 +998,24 @@ def _AddMergeFromMethod(cls):
   cls.MergeFrom = MergeFrom
 
 
+def _AddWhichOneofMethod(message_descriptor, cls):
+  def WhichOneof(self, oneof_name):
+    """Returns the name of the currently set field inside a oneof, or None."""
+    try:
+      field = message_descriptor.oneofs_by_name[oneof_name]
+    except KeyError:
+      raise ValueError(
+          'Protocol message has no oneof "%s" field.' % oneof_name)
+
+    nested_field = self._oneofs.get(field, None)
+    if nested_field is not None and self.HasField(nested_field.name):
+      return nested_field.name
+    else:
+      return None
+
+  cls.WhichOneof = WhichOneof
+
+
 def _AddMessageMethods(message_descriptor, cls):
   """Adds implementations of all Message methods to cls."""
   _AddListFieldsMethod(message_descriptor, cls)
@@ -972,9 +1035,9 @@ def _AddMessageMethods(message_descriptor, cls):
   _AddMergeFromStringMethod(message_descriptor, cls)
   _AddIsInitializedMethod(message_descriptor, cls)
   _AddMergeFromMethod(cls)
+  _AddWhichOneofMethod(message_descriptor, cls)
 
-
-def _AddPrivateHelperMethods(cls):
+def _AddPrivateHelperMethods(message_descriptor, cls):
   """Adds implementation of private helper methods to cls."""
 
   def Modified(self):
@@ -992,8 +1055,20 @@ def _AddPrivateHelperMethods(cls):
       self._is_present_in_parent = True
       self._listener.Modified()
 
+  def _UpdateOneofState(self, field):
+    """Sets field as the active field in its containing oneof.
+
+    Will also delete currently active field in the oneof, if it is different
+    from the argument. Does not mark the message as modified.
+    """
+    other_field = self._oneofs.setdefault(field.containing_oneof, field)
+    if other_field is not field:
+      del self._fields[other_field]
+      self._oneofs[field.containing_oneof] = field
+
   cls._Modified = Modified
   cls.SetInParent = Modified
+  cls._UpdateOneofState = _UpdateOneofState
 
 
 class _Listener(object):
@@ -1042,6 +1117,27 @@ class _Listener(object):
       pass
 
 
+class _OneofListener(_Listener):
+  """Special listener implementation for setting composite oneof fields."""
+
+  def __init__(self, parent_message, field):
+    """Args:
+      parent_message: The message whose _Modified() method we should call when
+        we receive Modified() messages.
+      field: The descriptor of the field being set in the parent message.
+    """
+    super(_OneofListener, self).__init__(parent_message)
+    self._field = field
+
+  def Modified(self):
+    """Also updates the state of the containing oneof in the parent message."""
+    try:
+      self._parent_message_weakref._UpdateOneofState(self._field)
+      super(_OneofListener, self).Modified()
+    except ReferenceError:
+      pass
+
+
 # TODO(robinson): Move elsewhere?  This file is getting pretty ridiculous...
 # TODO(robinson): Unify error handling of "unknown extension" crap.
 # TODO(robinson): Support iteritems()-style iteration over all
@@ -1133,9 +1229,10 @@ class _ExtensionDict(object):
     # It's slightly wasteful to lookup the type checker each time,
     # but we expect this to be a vanishingly uncommon case anyway.
     type_checker = type_checkers.GetTypeChecker(
-        extension_handle.cpp_type, extension_handle.type)
-    type_checker.CheckValue(value)
-    self._extended_message._fields[extension_handle] = value
+        extension_handle)
+    # pylint: disable=protected-access
+    self._extended_message._fields[extension_handle] = (
+      type_checker.CheckValue(value))
     self._extended_message._Modified()
 
   def _FindExtensionByName(self, name):
diff --git a/python/google/protobuf/internal/reflection_cpp_generated_test.py b/python/google/protobuf/internal/reflection_cpp2_generated_test.py
index 2a0a5124..d7fce5fa 100755
--- a/python/google/protobuf/internal/reflection_cpp_generated_test.py
+++ b/python/google/protobuf/internal/reflection_cpp2_generated_test.py
@@ -37,17 +37,19 @@ __author__ = 'jasonh@google.com (Jason Hsueh)'
 
 import os
 os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION'] = 'cpp'
+os.environ['PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION'] = '2'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf.internal import api_implementation
 from google.protobuf.internal import more_extensions_dynamic_pb2
 from google.protobuf.internal import more_extensions_pb2
 from google.protobuf.internal.reflection_test import *
 
 
-class ReflectionCppTest(unittest.TestCase):
+class ReflectionCppTest(basetest.TestCase):
   def testImplementationSetting(self):
     self.assertEqual('cpp', api_implementation.Type())
+    self.assertEqual(2, api_implementation.Version())
 
   def testExtensionOfGeneratedTypeInDynamicFile(self):
     """Tests that a file built dynamically can extend a generated C++ type.
@@ -87,5 +89,6 @@ class ReflectionCppTest(unittest.TestCase):
         pb2.Extensions[more_extensions_dynamic_pb2.dynamic_message_extension].a)
 
 
+
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/reflection_test.py b/python/google/protobuf/internal/reflection_test.py
index ed286461..b3c414c7 100755
--- a/python/google/protobuf/internal/reflection_test.py
+++ b/python/google/protobuf/internal/reflection_test.py
@@ -37,11 +37,12 @@ pure-Python protocol compiler.
 
 __author__ = 'robinson@google.com (Will Robinson)'
 
+import copy
 import gc
 import operator
 import struct
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import unittest_import_pb2
 from google.protobuf import unittest_mset_pb2
 from google.protobuf import unittest_pb2
@@ -49,6 +50,7 @@ from google.protobuf import descriptor_pb2
 from google.protobuf import descriptor
 from google.protobuf import message
 from google.protobuf import reflection
+from google.protobuf import text_format
 from google.protobuf.internal import api_implementation
 from google.protobuf.internal import more_extensions_pb2
 from google.protobuf.internal import more_messages_pb2
@@ -102,7 +104,7 @@ class _MiniDecoder(object):
     return self._pos == len(self._bytes)
 
 
-class ReflectionTest(unittest.TestCase):
+class ReflectionTest(basetest.TestCase):
 
   def assertListsEqual(self, values, others):
     self.assertEqual(len(values), len(others))
@@ -533,7 +535,7 @@ class ReflectionTest(unittest.TestCase):
     self.assertEqual(0.0, proto.optional_double)
     self.assertEqual(False, proto.optional_bool)
     self.assertEqual('', proto.optional_string)
-    self.assertEqual('', proto.optional_bytes)
+    self.assertEqual(b'', proto.optional_bytes)
 
     self.assertEqual(41, proto.default_int32)
     self.assertEqual(42, proto.default_int64)
@@ -549,7 +551,7 @@ class ReflectionTest(unittest.TestCase):
     self.assertEqual(52e3, proto.default_double)
     self.assertEqual(True, proto.default_bool)
     self.assertEqual('hello', proto.default_string)
-    self.assertEqual('world', proto.default_bytes)
+    self.assertEqual(b'world', proto.default_bytes)
     self.assertEqual(unittest_pb2.TestAllTypes.BAR, proto.default_nested_enum)
     self.assertEqual(unittest_pb2.FOREIGN_BAR, proto.default_foreign_enum)
     self.assertEqual(unittest_import_pb2.IMPORT_BAR,
@@ -566,6 +568,17 @@ class ReflectionTest(unittest.TestCase):
     proto = unittest_pb2.TestAllTypes()
     self.assertRaises(ValueError, proto.ClearField, 'nonexistent_field')
 
+  def testClearRemovesChildren(self):
+    # Make sure there aren't any implementation bugs that are only partially
+    # clearing the message (which can happen in the more complex C++
+    # implementation which has parallel message lists).
+    proto = unittest_pb2.TestRequiredForeign()
+    for i in range(10):
+      proto.repeated_message.add()
+    proto2 = unittest_pb2.TestRequiredForeign()
+    proto.CopyFrom(proto2)
+    self.assertRaises(IndexError, lambda: proto.repeated_message[5])
+
   def testDisallowedAssignments(self):
     # It's illegal to assign values directly to repeated fields
     # or to nonrepeated composite fields.  Ensure that this fails.
@@ -594,6 +607,30 @@ class ReflectionTest(unittest.TestCase):
     self.assertRaises(TypeError, setattr, proto, 'optional_string', 10)
     self.assertRaises(TypeError, setattr, proto, 'optional_bytes', 10)
 
+  def testIntegerTypes(self):
+    def TestGetAndDeserialize(field_name, value, expected_type):
+      proto = unittest_pb2.TestAllTypes()
+      setattr(proto, field_name, value)
+      self.assertTrue(isinstance(getattr(proto, field_name), expected_type))
+      proto2 = unittest_pb2.TestAllTypes()
+      proto2.ParseFromString(proto.SerializeToString())
+      self.assertTrue(isinstance(getattr(proto2, field_name), expected_type))
+
+    TestGetAndDeserialize('optional_int32', 1, int)
+    TestGetAndDeserialize('optional_int32', 1 << 30, int)
+    TestGetAndDeserialize('optional_uint32', 1 << 30, int)
+    if struct.calcsize('L') == 4:
+      # Python only has signed ints, so 32-bit python can't fit an uint32
+      # in an int.
+      TestGetAndDeserialize('optional_uint32', 1 << 31, long)
+    else:
+      # 64-bit python can fit uint32 inside an int
+      TestGetAndDeserialize('optional_uint32', 1 << 31, int)
+    TestGetAndDeserialize('optional_int64', 1 << 30, long)
+    TestGetAndDeserialize('optional_int64', 1 << 60, long)
+    TestGetAndDeserialize('optional_uint64', 1 << 30, long)
+    TestGetAndDeserialize('optional_uint64', 1 << 60, long)
+
   def testSingleScalarBoundsChecking(self):
     def TestMinAndMaxIntegers(field_name, expected_min, expected_max):
       pb = unittest_pb2.TestAllTypes()
@@ -613,29 +650,6 @@ class ReflectionTest(unittest.TestCase):
     pb.optional_nested_enum = 1
     self.assertEqual(1, pb.optional_nested_enum)
 
-    # Invalid enum values.
-    pb.optional_nested_enum = 0
-    self.assertEqual(0, pb.optional_nested_enum)
-
-    bytes_size_before = pb.ByteSize()
-
-    pb.optional_nested_enum = 4
-    self.assertEqual(4, pb.optional_nested_enum)
-
-    pb.optional_nested_enum = 0
-    self.assertEqual(0, pb.optional_nested_enum)
-
-    # Make sure that setting the same enum field doesn't just add unknown
-    # fields (but overwrites them).
-    self.assertEqual(bytes_size_before, pb.ByteSize())
-
-    # Is the invalid value preserved after serialization?
-    serialized = pb.SerializeToString()
-    pb2 = unittest_pb2.TestAllTypes()
-    pb2.ParseFromString(serialized)
-    self.assertEqual(0, pb2.optional_nested_enum)
-    self.assertEqual(pb, pb2)
-
   def testRepeatedScalarTypeSafety(self):
     proto = unittest_pb2.TestAllTypes()
     self.assertRaises(TypeError, proto.repeated_int32.append, 1.1)
@@ -749,9 +763,9 @@ class ReflectionTest(unittest.TestCase):
                      unittest_pb2.ForeignEnum.items())
 
     proto = unittest_pb2.TestAllTypes()
-    self.assertEqual(['FOO', 'BAR', 'BAZ'], proto.NestedEnum.keys())
-    self.assertEqual([1, 2, 3], proto.NestedEnum.values())
-    self.assertEqual([('FOO', 1), ('BAR', 2), ('BAZ', 3)],
+    self.assertEqual(['FOO', 'BAR', 'BAZ', 'NEG'], proto.NestedEnum.keys())
+    self.assertEqual([1, 2, 3, -1], proto.NestedEnum.values())
+    self.assertEqual([('FOO', 1), ('BAR', 2), ('BAZ', 3), ('NEG', -1)],
                      proto.NestedEnum.items())
 
   def testRepeatedScalars(self):
@@ -1155,6 +1169,14 @@ class ReflectionTest(unittest.TestCase):
     self.assertTrue(required is not extendee_proto.Extensions[extension])
     self.assertTrue(not extendee_proto.HasExtension(extension))
 
+  def testRegisteredExtensions(self):
+    self.assertTrue('protobuf_unittest.optional_int32_extension' in
+                    unittest_pb2.TestAllExtensions._extensions_by_name)
+    self.assertTrue(1 in unittest_pb2.TestAllExtensions._extensions_by_number)
+    # Make sure extensions haven't been registered into types that shouldn't
+    # have any.
+    self.assertEquals(0, len(unittest_pb2.TestAllTypes._extensions_by_name))
+
   # If message A directly contains message B, and
   # a.HasField('b') is currently False, then mutating any
   # extension in B should change a.HasField('b') to True
@@ -1451,6 +1473,19 @@ class ReflectionTest(unittest.TestCase):
     proto2 = unittest_pb2.TestAllExtensions()
     self.assertRaises(TypeError, proto1.CopyFrom, proto2)
 
+  def testDeepCopy(self):
+    proto1 = unittest_pb2.TestAllTypes()
+    proto1.optional_int32 = 1
+    proto2 = copy.deepcopy(proto1)
+    self.assertEqual(1, proto2.optional_int32)
+
+    proto1.repeated_int32.append(2)
+    proto1.repeated_int32.append(3)
+    container = copy.deepcopy(proto1.repeated_int32)
+    self.assertEqual([2, 3], container)
+
+    # TODO(anuraag): Implement deepcopy for repeated composite / extension dict
+
   def testClear(self):
     proto = unittest_pb2.TestAllTypes()
     # C++ implementation does not support lazy fields right now so leave it
@@ -1496,11 +1531,23 @@ class ReflectionTest(unittest.TestCase):
     self.assertEqual(6, foreign.c)
     nested.bb = 15
     foreign.c = 16
-    self.assertTrue(not proto.HasField('optional_nested_message'))
+    self.assertFalse(proto.HasField('optional_nested_message'))
     self.assertEqual(0, proto.optional_nested_message.bb)
-    self.assertTrue(not proto.HasField('optional_foreign_message'))
+    self.assertFalse(proto.HasField('optional_foreign_message'))
     self.assertEqual(0, proto.optional_foreign_message.c)
 
+  def testOneOf(self):
+    proto = unittest_pb2.TestAllTypes()
+    proto.oneof_uint32 = 10
+    proto.oneof_nested_message.bb = 11
+    self.assertEqual(11, proto.oneof_nested_message.bb)
+    self.assertFalse(proto.HasField('oneof_uint32'))
+    nested = proto.oneof_nested_message
+    proto.oneof_string = 'abc'
+    self.assertEqual('abc', proto.oneof_string)
+    self.assertEqual(11, nested.bb)
+    self.assertFalse(proto.HasField('oneof_nested_message'))
+
   def assertInitialized(self, proto):
     self.assertTrue(proto.IsInitialized())
     # Neither method should raise an exception.
@@ -1571,6 +1618,40 @@ class ReflectionTest(unittest.TestCase):
     self.assertFalse(proto.IsInitialized(errors))
     self.assertEqual(errors, ['a', 'b', 'c'])
 
+  @basetest.unittest.skipIf(
+      api_implementation.Type() != 'cpp' or api_implementation.Version() != 2,
+      'Errors are only available from the most recent C++ implementation.')
+  def testFileDescriptorErrors(self):
+    file_name = 'test_file_descriptor_errors.proto'
+    package_name = 'test_file_descriptor_errors.proto'
+    file_descriptor_proto = descriptor_pb2.FileDescriptorProto()
+    file_descriptor_proto.name = file_name
+    file_descriptor_proto.package = package_name
+    m1 = file_descriptor_proto.message_type.add()
+    m1.name = 'msg1'
+    # Compiles the proto into the C++ descriptor pool
+    descriptor.FileDescriptor(
+        file_name,
+        package_name,
+        serialized_pb=file_descriptor_proto.SerializeToString())
+    # Add a FileDescriptorProto that has duplicate symbols
+    another_file_name = 'another_test_file_descriptor_errors.proto'
+    file_descriptor_proto.name = another_file_name
+    m2 = file_descriptor_proto.message_type.add()
+    m2.name = 'msg2'
+    with self.assertRaises(TypeError) as cm:
+      descriptor.FileDescriptor(
+          another_file_name,
+          package_name,
+          serialized_pb=file_descriptor_proto.SerializeToString())
+      self.assertTrue(hasattr(cm, 'exception'), '%s not raised' %
+                      getattr(cm.expected, '__name__', cm.expected))
+      self.assertIn('test_file_descriptor_errors.proto', str(cm.exception))
+      # Error message will say something about this definition being a
+      # duplicate, though we don't check the message exactly to avoid a
+      # dependency on the C++ logging code.
+      self.assertIn('test_file_descriptor_errors.msg1', str(cm.exception))
+
   def testStringUTF8Encoding(self):
     proto = unittest_pb2.TestAllTypes()
 
@@ -1588,17 +1669,15 @@ class ReflectionTest(unittest.TestCase):
     proto.optional_string = str('Testing')
     self.assertEqual(proto.optional_string, unicode('Testing'))
 
-    if api_implementation.Type() == 'python':
-      # Values of type 'str' are also accepted as long as they can be
-      # encoded in UTF-8.
-      self.assertEqual(type(proto.optional_string), str)
-
     # Try to assign a 'str' value which contains bytes that aren't 7-bit ASCII.
     self.assertRaises(ValueError,
-                      setattr, proto, 'optional_string', str('a\x80a'))
-    # Assign a 'str' object which contains a UTF-8 encoded string.
-    self.assertRaises(ValueError,
-                      setattr, proto, 'optional_string', 'Тест')
+                      setattr, proto, 'optional_string', b'a\x80a')
+    if str is bytes:  # PY2
+      # Assign a 'str' object which contains a UTF-8 encoded string.
+      self.assertRaises(ValueError,
+                        setattr, proto, 'optional_string', 'Тест')
+    else:
+      proto.optional_string = 'Тест'
     # No exception thrown.
     proto.optional_string = 'abc'
 
@@ -1621,7 +1700,8 @@ class ReflectionTest(unittest.TestCase):
     self.assertEqual(proto.ByteSize(), len(serialized))
 
     raw = unittest_mset_pb2.RawMessageSet()
-    raw.MergeFromString(serialized)
+    bytes_read = raw.MergeFromString(serialized)
+    self.assertEqual(len(serialized), bytes_read)
 
     message2 = unittest_mset_pb2.TestMessageSetExtension2()
 
@@ -1632,7 +1712,8 @@ class ReflectionTest(unittest.TestCase):
     # Check the actual bytes on the wire.
     self.assertTrue(
         raw.item[0].message.endswith(test_utf8_bytes))
-    message2.MergeFromString(raw.item[0].message)
+    bytes_read = message2.MergeFromString(raw.item[0].message)
+    self.assertEqual(len(raw.item[0].message), bytes_read)
 
     self.assertEqual(type(message2.str), unicode)
     self.assertEqual(message2.str, test_utf8)
@@ -1643,17 +1724,22 @@ class ReflectionTest(unittest.TestCase):
     # MergeFromString and thus has no way to throw the exception.
     #
     # The pure Python API always returns objects of type 'unicode' (UTF-8
-    # encoded), or 'str' (in 7 bit ASCII).
-    bytes = raw.item[0].message.replace(
-        test_utf8_bytes, len(test_utf8_bytes) * '\xff')
+    # encoded), or 'bytes' (in 7 bit ASCII).
+    badbytes = raw.item[0].message.replace(
+        test_utf8_bytes, len(test_utf8_bytes) * b'\xff')
 
     unicode_decode_failed = False
     try:
-      message2.MergeFromString(bytes)
-    except UnicodeDecodeError as e:
+      message2.MergeFromString(badbytes)
+    except UnicodeDecodeError:
       unicode_decode_failed = True
     string_field = message2.str
-    self.assertTrue(unicode_decode_failed or type(string_field) == str)
+    self.assertTrue(unicode_decode_failed or type(string_field) is bytes)
+
+  def testBytesInTextFormat(self):
+    proto = unittest_pb2.TestAllTypes(optional_bytes=b'\x00\x7f\x80\xff')
+    self.assertEqual(u'optional_bytes: "\\000\\177\\200\\377"\n',
+                     unicode(proto))
 
   def testEmptyNestedMessage(self):
     proto = unittest_pb2.TestAllTypes()
@@ -1667,16 +1753,19 @@ class ReflectionTest(unittest.TestCase):
     self.assertTrue(proto.HasField('optional_nested_message'))
 
     proto = unittest_pb2.TestAllTypes()
-    proto.optional_nested_message.MergeFromString('')
+    bytes_read = proto.optional_nested_message.MergeFromString(b'')
+    self.assertEqual(0, bytes_read)
     self.assertTrue(proto.HasField('optional_nested_message'))
 
     proto = unittest_pb2.TestAllTypes()
-    proto.optional_nested_message.ParseFromString('')
+    proto.optional_nested_message.ParseFromString(b'')
     self.assertTrue(proto.HasField('optional_nested_message'))
 
     serialized = proto.SerializeToString()
     proto2 = unittest_pb2.TestAllTypes()
-    proto2.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        proto2.MergeFromString(serialized))
     self.assertTrue(proto2.HasField('optional_nested_message'))
 
   def testSetInParent(self):
@@ -1690,7 +1779,7 @@ class ReflectionTest(unittest.TestCase):
 #  into separate TestCase classes.
 
 
-class TestAllTypesEqualityTest(unittest.TestCase):
+class TestAllTypesEqualityTest(basetest.TestCase):
 
   def setUp(self):
     self.first_proto = unittest_pb2.TestAllTypes()
@@ -1706,7 +1795,7 @@ class TestAllTypesEqualityTest(unittest.TestCase):
     self.assertEqual(self.first_proto, self.second_proto)
 
 
-class FullProtosEqualityTest(unittest.TestCase):
+class FullProtosEqualityTest(basetest.TestCase):
 
   """Equality tests using completely-full protos as a starting point."""
 
@@ -1792,7 +1881,7 @@ class FullProtosEqualityTest(unittest.TestCase):
     self.assertEqual(self.first_proto, self.second_proto)
 
 
-class ExtensionEqualityTest(unittest.TestCase):
+class ExtensionEqualityTest(basetest.TestCase):
 
   def testExtensionEquality(self):
     first_proto = unittest_pb2.TestAllExtensions()
@@ -1825,7 +1914,7 @@ class ExtensionEqualityTest(unittest.TestCase):
     self.assertEqual(first_proto, second_proto)
 
 
-class MutualRecursionEqualityTest(unittest.TestCase):
+class MutualRecursionEqualityTest(basetest.TestCase):
 
   def testEqualityWithMutualRecursion(self):
     first_proto = unittest_pb2.TestMutualRecursionA()
@@ -1837,7 +1926,7 @@ class MutualRecursionEqualityTest(unittest.TestCase):
     self.assertEqual(first_proto, second_proto)
 
 
-class ByteSizeTest(unittest.TestCase):
+class ByteSizeTest(basetest.TestCase):
 
   def setUp(self):
     self.proto = unittest_pb2.TestAllTypes()
@@ -2133,14 +2222,16 @@ class ByteSizeTest(unittest.TestCase):
 #   * Handling of empty submessages (with and without "has"
 #     bits set).
 
-class SerializationTest(unittest.TestCase):
+class SerializationTest(basetest.TestCase):
 
   def testSerializeEmtpyMessage(self):
     first_proto = unittest_pb2.TestAllTypes()
     second_proto = unittest_pb2.TestAllTypes()
     serialized = first_proto.SerializeToString()
     self.assertEqual(first_proto.ByteSize(), len(serialized))
-    second_proto.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        second_proto.MergeFromString(serialized))
     self.assertEqual(first_proto, second_proto)
 
   def testSerializeAllFields(self):
@@ -2149,7 +2240,9 @@ class SerializationTest(unittest.TestCase):
     test_util.SetAllFields(first_proto)
     serialized = first_proto.SerializeToString()
     self.assertEqual(first_proto.ByteSize(), len(serialized))
-    second_proto.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        second_proto.MergeFromString(serialized))
     self.assertEqual(first_proto, second_proto)
 
   def testSerializeAllExtensions(self):
@@ -2157,7 +2250,19 @@ class SerializationTest(unittest.TestCase):
     second_proto = unittest_pb2.TestAllExtensions()
     test_util.SetAllExtensions(first_proto)
     serialized = first_proto.SerializeToString()
-    second_proto.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        second_proto.MergeFromString(serialized))
+    self.assertEqual(first_proto, second_proto)
+
+  def testSerializeWithOptionalGroup(self):
+    first_proto = unittest_pb2.TestAllTypes()
+    second_proto = unittest_pb2.TestAllTypes()
+    first_proto.optionalgroup.a = 242
+    serialized = first_proto.SerializeToString()
+    self.assertEqual(
+        len(serialized),
+        second_proto.MergeFromString(serialized))
     self.assertEqual(first_proto, second_proto)
 
   def testSerializeNegativeValues(self):
@@ -2249,7 +2354,9 @@ class SerializationTest(unittest.TestCase):
     second_proto.optional_int32 = 100
     second_proto.optional_nested_message.bb = 999
 
-    second_proto.MergeFromString(serialized)
+    bytes_parsed = second_proto.MergeFromString(serialized)
+    self.assertEqual(len(serialized), bytes_parsed)
+
     # Ensure that we append to repeated fields.
     self.assertEqual(['baz', 'foobar'], list(second_proto.repeated_string))
     # Ensure that we overwrite nonrepeatd scalars.
@@ -2274,20 +2381,28 @@ class SerializationTest(unittest.TestCase):
     raw = unittest_mset_pb2.RawMessageSet()
     self.assertEqual(False,
                      raw.DESCRIPTOR.GetOptions().message_set_wire_format)
-    raw.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        raw.MergeFromString(serialized))
     self.assertEqual(2, len(raw.item))
 
     message1 = unittest_mset_pb2.TestMessageSetExtension1()
-    message1.MergeFromString(raw.item[0].message)
+    self.assertEqual(
+        len(raw.item[0].message),
+        message1.MergeFromString(raw.item[0].message))
     self.assertEqual(123, message1.i)
 
     message2 = unittest_mset_pb2.TestMessageSetExtension2()
-    message2.MergeFromString(raw.item[1].message)
+    self.assertEqual(
+        len(raw.item[1].message),
+        message2.MergeFromString(raw.item[1].message))
     self.assertEqual('foo', message2.str)
 
     # Deserialize using the MessageSet wire format.
     proto2 = unittest_mset_pb2.TestMessageSet()
-    proto2.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        proto2.MergeFromString(serialized))
     self.assertEqual(123, proto2.Extensions[extension1].i)
     self.assertEqual('foo', proto2.Extensions[extension2].str)
 
@@ -2327,7 +2442,9 @@ class SerializationTest(unittest.TestCase):
 
     # Parse message using the message set wire format.
     proto = unittest_mset_pb2.TestMessageSet()
-    proto.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        proto.MergeFromString(serialized))
 
     # Check that the message parsed well.
     extension_message1 = unittest_mset_pb2.TestMessageSetExtension1
@@ -2345,7 +2462,9 @@ class SerializationTest(unittest.TestCase):
     proto2 = unittest_pb2.TestEmptyMessage()
 
     # Parsing this message should succeed.
-    proto2.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        proto2.MergeFromString(serialized))
 
     # Now test with a int64 field set.
     proto = unittest_pb2.TestAllTypes()
@@ -2355,7 +2474,9 @@ class SerializationTest(unittest.TestCase):
     # unknown.
     proto2 = unittest_pb2.TestEmptyMessage()
     # Parsing this message should succeed.
-    proto2.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        proto2.MergeFromString(serialized))
 
   def _CheckRaises(self, exc_class, callable_obj, exception):
     """This method checks if the excpetion type and message are as expected."""
@@ -2406,11 +2527,15 @@ class SerializationTest(unittest.TestCase):
     partial = proto.SerializePartialToString()
 
     proto2 = unittest_pb2.TestRequired()
-    proto2.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        proto2.MergeFromString(serialized))
     self.assertEqual(1, proto2.a)
     self.assertEqual(2, proto2.b)
     self.assertEqual(3, proto2.c)
-    proto2.ParseFromString(partial)
+    self.assertEqual(
+        len(partial),
+        proto2.MergeFromString(partial))
     self.assertEqual(1, proto2.a)
     self.assertEqual(2, proto2.b)
     self.assertEqual(3, proto2.c)
@@ -2478,7 +2603,9 @@ class SerializationTest(unittest.TestCase):
     second_proto.packed_double.extend([1.0, 2.0])
     second_proto.packed_sint32.append(4)
 
-    second_proto.MergeFromString(serialized)
+    self.assertEqual(
+        len(serialized),
+        second_proto.MergeFromString(serialized))
     self.assertEqual([3, 1, 2], second_proto.packed_int32)
     self.assertEqual([1.0, 2.0, 3.0], second_proto.packed_double)
     self.assertEqual([4], second_proto.packed_sint32)
@@ -2511,7 +2638,10 @@ class SerializationTest(unittest.TestCase):
     unpacked = unittest_pb2.TestUnpackedTypes()
     test_util.SetAllUnpackedFields(unpacked)
     packed = unittest_pb2.TestPackedTypes()
-    packed.MergeFromString(unpacked.SerializeToString())
+    serialized = unpacked.SerializeToString()
+    self.assertEqual(
+        len(serialized),
+        packed.MergeFromString(serialized))
     expected = unittest_pb2.TestPackedTypes()
     test_util.SetAllPackedFields(expected)
     self.assertEqual(expected, packed)
@@ -2520,7 +2650,10 @@ class SerializationTest(unittest.TestCase):
     packed = unittest_pb2.TestPackedTypes()
     test_util.SetAllPackedFields(packed)
     unpacked = unittest_pb2.TestUnpackedTypes()
-    unpacked.MergeFromString(packed.SerializeToString())
+    serialized = packed.SerializeToString()
+    self.assertEqual(
+        len(serialized),
+        unpacked.MergeFromString(serialized))
     expected = unittest_pb2.TestUnpackedTypes()
     test_util.SetAllUnpackedFields(expected)
     self.assertEqual(expected, unpacked)
@@ -2572,7 +2705,7 @@ class SerializationTest(unittest.TestCase):
         optional_int32=1,
         optional_string='foo',
         optional_bool=True,
-        optional_bytes='bar',
+        optional_bytes=b'bar',
         optional_nested_message=unittest_pb2.TestAllTypes.NestedMessage(bb=1),
         optional_foreign_message=unittest_pb2.ForeignMessage(c=1),
         optional_nested_enum=unittest_pb2.TestAllTypes.FOO,
@@ -2590,7 +2723,7 @@ class SerializationTest(unittest.TestCase):
     self.assertEqual(1, proto.optional_int32)
     self.assertEqual('foo', proto.optional_string)
     self.assertEqual(True, proto.optional_bool)
-    self.assertEqual('bar', proto.optional_bytes)
+    self.assertEqual(b'bar', proto.optional_bytes)
     self.assertEqual(1, proto.optional_nested_message.bb)
     self.assertEqual(1, proto.optional_foreign_message.c)
     self.assertEqual(unittest_pb2.TestAllTypes.FOO,
@@ -2640,7 +2773,7 @@ class SerializationTest(unittest.TestCase):
     self.assertEqual(3, proto.repeated_int32[2])
 
 
-class OptionsTest(unittest.TestCase):
+class OptionsTest(basetest.TestCase):
 
   def testMessageOptions(self):
     proto = unittest_mset_pb2.TestMessageSet()
@@ -2667,5 +2800,135 @@ class OptionsTest(unittest.TestCase):
 
 
 
+class ClassAPITest(basetest.TestCase):
+
+  def testMakeClassWithNestedDescriptor(self):
+    leaf_desc = descriptor.Descriptor('leaf', 'package.parent.child.leaf', '',
+                                      containing_type=None, fields=[],
+                                      nested_types=[], enum_types=[],
+                                      extensions=[])
+    child_desc = descriptor.Descriptor('child', 'package.parent.child', '',
+                                       containing_type=None, fields=[],
+                                       nested_types=[leaf_desc], enum_types=[],
+                                       extensions=[])
+    sibling_desc = descriptor.Descriptor('sibling', 'package.parent.sibling',
+                                         '', containing_type=None, fields=[],
+                                         nested_types=[], enum_types=[],
+                                         extensions=[])
+    parent_desc = descriptor.Descriptor('parent', 'package.parent', '',
+                                        containing_type=None, fields=[],
+                                        nested_types=[child_desc, sibling_desc],
+                                        enum_types=[], extensions=[])
+    message_class = reflection.MakeClass(parent_desc)
+    self.assertIn('child', message_class.__dict__)
+    self.assertIn('sibling', message_class.__dict__)
+    self.assertIn('leaf', message_class.child.__dict__)
+
+  def _GetSerializedFileDescriptor(self, name):
+    """Get a serialized representation of a test FileDescriptorProto.
+
+    Args:
+      name: All calls to this must use a unique message name, to avoid
+          collisions in the cpp descriptor pool.
+    Returns:
+      A string containing the serialized form of a test FileDescriptorProto.
+    """
+    file_descriptor_str = (
+        'message_type {'
+        '  name: "' + name + '"'
+        '  field {'
+        '    name: "flat"'
+        '    number: 1'
+        '    label: LABEL_REPEATED'
+        '    type: TYPE_UINT32'
+        '  }'
+        '  field {'
+        '    name: "bar"'
+        '    number: 2'
+        '    label: LABEL_OPTIONAL'
+        '    type: TYPE_MESSAGE'
+        '    type_name: "Bar"'
+        '  }'
+        '  nested_type {'
+        '    name: "Bar"'
+        '    field {'
+        '      name: "baz"'
+        '      number: 3'
+        '      label: LABEL_OPTIONAL'
+        '      type: TYPE_MESSAGE'
+        '      type_name: "Baz"'
+        '    }'
+        '    nested_type {'
+        '      name: "Baz"'
+        '      enum_type {'
+        '        name: "deep_enum"'
+        '        value {'
+        '          name: "VALUE_A"'
+        '          number: 0'
+        '        }'
+        '      }'
+        '      field {'
+        '        name: "deep"'
+        '        number: 4'
+        '        label: LABEL_OPTIONAL'
+        '        type: TYPE_UINT32'
+        '      }'
+        '    }'
+        '  }'
+        '}')
+    file_descriptor = descriptor_pb2.FileDescriptorProto()
+    text_format.Merge(file_descriptor_str, file_descriptor)
+    return file_descriptor.SerializeToString()
+
+  def testParsingFlatClassWithExplicitClassDeclaration(self):
+    """Test that the generated class can parse a flat message."""
+    file_descriptor = descriptor_pb2.FileDescriptorProto()
+    file_descriptor.ParseFromString(self._GetSerializedFileDescriptor('A'))
+    msg_descriptor = descriptor.MakeDescriptor(
+        file_descriptor.message_type[0])
+
+    class MessageClass(message.Message):
+      __metaclass__ = reflection.GeneratedProtocolMessageType
+      DESCRIPTOR = msg_descriptor
+    msg = MessageClass()
+    msg_str = (
+        'flat: 0 '
+        'flat: 1 '
+        'flat: 2 ')
+    text_format.Merge(msg_str, msg)
+    self.assertEqual(msg.flat, [0, 1, 2])
+
+  def testParsingFlatClass(self):
+    """Test that the generated class can parse a flat message."""
+    file_descriptor = descriptor_pb2.FileDescriptorProto()
+    file_descriptor.ParseFromString(self._GetSerializedFileDescriptor('B'))
+    msg_descriptor = descriptor.MakeDescriptor(
+        file_descriptor.message_type[0])
+    msg_class = reflection.MakeClass(msg_descriptor)
+    msg = msg_class()
+    msg_str = (
+        'flat: 0 '
+        'flat: 1 '
+        'flat: 2 ')
+    text_format.Merge(msg_str, msg)
+    self.assertEqual(msg.flat, [0, 1, 2])
+
+  def testParsingNestedClass(self):
+    """Test that the generated class can parse a nested message."""
+    file_descriptor = descriptor_pb2.FileDescriptorProto()
+    file_descriptor.ParseFromString(self._GetSerializedFileDescriptor('C'))
+    msg_descriptor = descriptor.MakeDescriptor(
+        file_descriptor.message_type[0])
+    msg_class = reflection.MakeClass(msg_descriptor)
+    msg = msg_class()
+    msg_str = (
+        'bar {'
+        '  baz {'
+        '    deep: 4'
+        '  }'
+        '}')
+    text_format.Merge(msg_str, msg)
+    self.assertEqual(msg.bar.baz.deep, 4)
+
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/service_reflection_test.py b/python/google/protobuf/internal/service_reflection_test.py
index e04f8252..ef0981d9 100755
--- a/python/google/protobuf/internal/service_reflection_test.py
+++ b/python/google/protobuf/internal/service_reflection_test.py
@@ -34,13 +34,13 @@
 
 __author__ = 'petar@google.com (Petar Petrov)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import unittest_pb2
 from google.protobuf import service_reflection
 from google.protobuf import service
 
 
-class FooUnitTest(unittest.TestCase):
+class FooUnitTest(basetest.TestCase):
 
   def testService(self):
     class MockRpcChannel(service.RpcChannel):
@@ -133,4 +133,4 @@ class FooUnitTest(unittest.TestCase):
 
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/symbol_database_test.py b/python/google/protobuf/internal/symbol_database_test.py
new file mode 100644
index 00000000..80bc8d6e
--- /dev/null
+++ b/python/google/protobuf/internal/symbol_database_test.py
@@ -0,0 +1,120 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Tests for google.protobuf.symbol_database."""
+
+from google.apputils import basetest
+from google.protobuf import unittest_pb2
+from google.protobuf import symbol_database
+
+
+class SymbolDatabaseTest(basetest.TestCase):
+
+  def _Database(self):
+    db = symbol_database.SymbolDatabase()
+    # Register representative types from unittest_pb2.
+    db.RegisterFileDescriptor(unittest_pb2.DESCRIPTOR)
+    db.RegisterMessage(unittest_pb2.TestAllTypes)
+    db.RegisterMessage(unittest_pb2.TestAllTypes.NestedMessage)
+    db.RegisterMessage(unittest_pb2.TestAllTypes.OptionalGroup)
+    db.RegisterMessage(unittest_pb2.TestAllTypes.RepeatedGroup)
+    db.RegisterEnumDescriptor(unittest_pb2.ForeignEnum.DESCRIPTOR)
+    db.RegisterEnumDescriptor(unittest_pb2.TestAllTypes.NestedEnum.DESCRIPTOR)
+    return db
+
+  def testGetPrototype(self):
+    instance = self._Database().GetPrototype(
+        unittest_pb2.TestAllTypes.DESCRIPTOR)
+    self.assertTrue(instance is unittest_pb2.TestAllTypes)
+
+  def testGetMessages(self):
+    messages = self._Database().GetMessages(
+        ['google/protobuf/unittest.proto'])
+    self.assertTrue(
+        unittest_pb2.TestAllTypes is
+        messages['protobuf_unittest.TestAllTypes'])
+
+  def testGetSymbol(self):
+    self.assertEquals(
+        unittest_pb2.TestAllTypes, self._Database().GetSymbol(
+            'protobuf_unittest.TestAllTypes'))
+    self.assertEquals(
+        unittest_pb2.TestAllTypes.NestedMessage, self._Database().GetSymbol(
+            'protobuf_unittest.TestAllTypes.NestedMessage'))
+    self.assertEquals(
+        unittest_pb2.TestAllTypes.OptionalGroup, self._Database().GetSymbol(
+            'protobuf_unittest.TestAllTypes.OptionalGroup'))
+    self.assertEquals(
+        unittest_pb2.TestAllTypes.RepeatedGroup, self._Database().GetSymbol(
+            'protobuf_unittest.TestAllTypes.RepeatedGroup'))
+
+  def testEnums(self):
+    # Check registration of types in the pool.
+    self.assertEquals(
+        'protobuf_unittest.ForeignEnum',
+        self._Database().pool.FindEnumTypeByName(
+            'protobuf_unittest.ForeignEnum').full_name)
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes.NestedEnum',
+        self._Database().pool.FindEnumTypeByName(
+            'protobuf_unittest.TestAllTypes.NestedEnum').full_name)
+
+  def testFindMessageTypeByName(self):
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes',
+        self._Database().pool.FindMessageTypeByName(
+            'protobuf_unittest.TestAllTypes').full_name)
+    self.assertEquals(
+        'protobuf_unittest.TestAllTypes.NestedMessage',
+        self._Database().pool.FindMessageTypeByName(
+            'protobuf_unittest.TestAllTypes.NestedMessage').full_name)
+
+  def testFindFindContainingSymbol(self):
+    # Lookup based on either enum or message.
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        self._Database().pool.FindFileContainingSymbol(
+            'protobuf_unittest.TestAllTypes.NestedEnum').name)
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        self._Database().pool.FindFileContainingSymbol(
+            'protobuf_unittest.TestAllTypes').name)
+
+  def testFindFileByName(self):
+    self.assertEquals(
+        'google/protobuf/unittest.proto',
+        self._Database().pool.FindFileByName(
+            'google/protobuf/unittest.proto').name)
+
+
+if __name__ == '__main__':
+  basetest.main()
diff --git a/python/google/protobuf/internal/test_util.py b/python/google/protobuf/internal/test_util.py
index be8ae7be..350d1c6d 100755
--- a/python/google/protobuf/internal/test_util.py
+++ b/python/google/protobuf/internal/test_util.py
@@ -66,14 +66,8 @@ def SetAllNonLazyFields(message):
   message.optional_float    = 111
   message.optional_double   = 112
   message.optional_bool     = True
-  # TODO(robinson): Firmly spec out and test how
-  # protos interact with unicode.  One specific example:
-  # what happens if we change the literal below to
-  # u'115'?  What *should* happen?  Still some discussion
-  # to finish with Kenton about bytes vs. strings
-  # and forcing everything to be utf8. :-/
-  message.optional_string   = '115'
-  message.optional_bytes    = '116'
+  message.optional_string   = u'115'
+  message.optional_bytes    = b'116'
 
   message.optionalgroup.a = 117
   message.optional_nested_message.bb = 118
@@ -85,8 +79,8 @@ def SetAllNonLazyFields(message):
   message.optional_foreign_enum = unittest_pb2.FOREIGN_BAZ
   message.optional_import_enum = unittest_import_pb2.IMPORT_BAZ
 
-  message.optional_string_piece = '124'
-  message.optional_cord = '125'
+  message.optional_string_piece = u'124'
+  message.optional_cord = u'125'
 
   #
   # Repeated fields.
@@ -105,8 +99,8 @@ def SetAllNonLazyFields(message):
   message.repeated_float.append(211)
   message.repeated_double.append(212)
   message.repeated_bool.append(True)
-  message.repeated_string.append('215')
-  message.repeated_bytes.append('216')
+  message.repeated_string.append(u'215')
+  message.repeated_bytes.append(b'216')
 
   message.repeatedgroup.add().a = 217
   message.repeated_nested_message.add().bb = 218
@@ -118,8 +112,8 @@ def SetAllNonLazyFields(message):
   message.repeated_foreign_enum.append(unittest_pb2.FOREIGN_BAR)
   message.repeated_import_enum.append(unittest_import_pb2.IMPORT_BAR)
 
-  message.repeated_string_piece.append('224')
-  message.repeated_cord.append('225')
+  message.repeated_string_piece.append(u'224')
+  message.repeated_cord.append(u'225')
 
   # Add a second one of each field.
   message.repeated_int32.append(301)
@@ -135,8 +129,8 @@ def SetAllNonLazyFields(message):
   message.repeated_float.append(311)
   message.repeated_double.append(312)
   message.repeated_bool.append(False)
-  message.repeated_string.append('315')
-  message.repeated_bytes.append('316')
+  message.repeated_string.append(u'315')
+  message.repeated_bytes.append(b'316')
 
   message.repeatedgroup.add().a = 317
   message.repeated_nested_message.add().bb = 318
@@ -148,8 +142,8 @@ def SetAllNonLazyFields(message):
   message.repeated_foreign_enum.append(unittest_pb2.FOREIGN_BAZ)
   message.repeated_import_enum.append(unittest_import_pb2.IMPORT_BAZ)
 
-  message.repeated_string_piece.append('324')
-  message.repeated_cord.append('325')
+  message.repeated_string_piece.append(u'324')
+  message.repeated_cord.append(u'325')
 
   #
   # Fields that have defaults.
@@ -169,7 +163,7 @@ def SetAllNonLazyFields(message):
   message.default_double = 412
   message.default_bool = False
   message.default_string = '415'
-  message.default_bytes = '416'
+  message.default_bytes = b'416'
 
   message.default_nested_enum = unittest_pb2.TestAllTypes.FOO
   message.default_foreign_enum = unittest_pb2.FOREIGN_FOO
@@ -178,6 +172,11 @@ def SetAllNonLazyFields(message):
   message.default_string_piece = '424'
   message.default_cord = '425'
 
+  message.oneof_uint32 = 601
+  message.oneof_nested_message.bb = 602
+  message.oneof_string = '603'
+  message.oneof_bytes = b'604'
+
 
 def SetAllFields(message):
   SetAllNonLazyFields(message)
@@ -212,8 +211,8 @@ def SetAllExtensions(message):
   extensions[pb2.optional_float_extension] = 111
   extensions[pb2.optional_double_extension] = 112
   extensions[pb2.optional_bool_extension] = True
-  extensions[pb2.optional_string_extension] = '115'
-  extensions[pb2.optional_bytes_extension] = '116'
+  extensions[pb2.optional_string_extension] = u'115'
+  extensions[pb2.optional_bytes_extension] = b'116'
 
   extensions[pb2.optionalgroup_extension].a = 117
   extensions[pb2.optional_nested_message_extension].bb = 118
@@ -227,8 +226,8 @@ def SetAllExtensions(message):
   extensions[pb2.optional_foreign_enum_extension] = pb2.FOREIGN_BAZ
   extensions[pb2.optional_import_enum_extension] = import_pb2.IMPORT_BAZ
 
-  extensions[pb2.optional_string_piece_extension] = '124'
-  extensions[pb2.optional_cord_extension] = '125'
+  extensions[pb2.optional_string_piece_extension] = u'124'
+  extensions[pb2.optional_cord_extension] = u'125'
 
   #
   # Repeated fields.
@@ -247,8 +246,8 @@ def SetAllExtensions(message):
   extensions[pb2.repeated_float_extension].append(211)
   extensions[pb2.repeated_double_extension].append(212)
   extensions[pb2.repeated_bool_extension].append(True)
-  extensions[pb2.repeated_string_extension].append('215')
-  extensions[pb2.repeated_bytes_extension].append('216')
+  extensions[pb2.repeated_string_extension].append(u'215')
+  extensions[pb2.repeated_bytes_extension].append(b'216')
 
   extensions[pb2.repeatedgroup_extension].add().a = 217
   extensions[pb2.repeated_nested_message_extension].add().bb = 218
@@ -260,8 +259,8 @@ def SetAllExtensions(message):
   extensions[pb2.repeated_foreign_enum_extension].append(pb2.FOREIGN_BAR)
   extensions[pb2.repeated_import_enum_extension].append(import_pb2.IMPORT_BAR)
 
-  extensions[pb2.repeated_string_piece_extension].append('224')
-  extensions[pb2.repeated_cord_extension].append('225')
+  extensions[pb2.repeated_string_piece_extension].append(u'224')
+  extensions[pb2.repeated_cord_extension].append(u'225')
 
   # Append a second one of each field.
   extensions[pb2.repeated_int32_extension].append(301)
@@ -277,8 +276,8 @@ def SetAllExtensions(message):
   extensions[pb2.repeated_float_extension].append(311)
   extensions[pb2.repeated_double_extension].append(312)
   extensions[pb2.repeated_bool_extension].append(False)
-  extensions[pb2.repeated_string_extension].append('315')
-  extensions[pb2.repeated_bytes_extension].append('316')
+  extensions[pb2.repeated_string_extension].append(u'315')
+  extensions[pb2.repeated_bytes_extension].append(b'316')
 
   extensions[pb2.repeatedgroup_extension].add().a = 317
   extensions[pb2.repeated_nested_message_extension].add().bb = 318
@@ -290,8 +289,8 @@ def SetAllExtensions(message):
   extensions[pb2.repeated_foreign_enum_extension].append(pb2.FOREIGN_BAZ)
   extensions[pb2.repeated_import_enum_extension].append(import_pb2.IMPORT_BAZ)
 
-  extensions[pb2.repeated_string_piece_extension].append('324')
-  extensions[pb2.repeated_cord_extension].append('325')
+  extensions[pb2.repeated_string_piece_extension].append(u'324')
+  extensions[pb2.repeated_cord_extension].append(u'325')
 
   #
   # Fields with defaults.
@@ -310,16 +309,21 @@ def SetAllExtensions(message):
   extensions[pb2.default_float_extension] = 411
   extensions[pb2.default_double_extension] = 412
   extensions[pb2.default_bool_extension] = False
-  extensions[pb2.default_string_extension] = '415'
-  extensions[pb2.default_bytes_extension] = '416'
+  extensions[pb2.default_string_extension] = u'415'
+  extensions[pb2.default_bytes_extension] = b'416'
 
   extensions[pb2.default_nested_enum_extension] = pb2.TestAllTypes.FOO
   extensions[pb2.default_foreign_enum_extension] = pb2.FOREIGN_FOO
   extensions[pb2.default_import_enum_extension] = import_pb2.IMPORT_FOO
 
-  extensions[pb2.default_string_piece_extension] = '424'
+  extensions[pb2.default_string_piece_extension] = u'424'
   extensions[pb2.default_cord_extension] = '425'
 
+  extensions[pb2.oneof_uint32_extension] = 601
+  extensions[pb2.oneof_nested_message_extension].bb = 602
+  extensions[pb2.oneof_string_extension] = u'603'
+  extensions[pb2.oneof_bytes_extension] = b'604'
+
 
 def SetAllFieldsAndExtensions(message):
   """Sets every field and extension in the message to a unique value.
@@ -358,7 +362,7 @@ def ExpectAllFieldsAndExtensionsInOrder(serialized):
   message.my_float = 1.0
   expected_strings.append(message.SerializeToString())
   message.Clear()
-  expected = ''.join(expected_strings)
+  expected = b''.join(expected_strings)
 
   if expected != serialized:
     raise ValueError('Expected %r, found %r' % (expected, serialized))
@@ -413,7 +417,7 @@ def ExpectAllFieldsSet(test_case, message):
   test_case.assertEqual(112, message.optional_double)
   test_case.assertEqual(True, message.optional_bool)
   test_case.assertEqual('115', message.optional_string)
-  test_case.assertEqual('116', message.optional_bytes)
+  test_case.assertEqual(b'116', message.optional_bytes)
 
   test_case.assertEqual(117, message.optionalgroup.a)
   test_case.assertEqual(118, message.optional_nested_message.bb)
@@ -472,7 +476,7 @@ def ExpectAllFieldsSet(test_case, message):
   test_case.assertEqual(212, message.repeated_double[0])
   test_case.assertEqual(True, message.repeated_bool[0])
   test_case.assertEqual('215', message.repeated_string[0])
-  test_case.assertEqual('216', message.repeated_bytes[0])
+  test_case.assertEqual(b'216', message.repeated_bytes[0])
 
   test_case.assertEqual(217, message.repeatedgroup[0].a)
   test_case.assertEqual(218, message.repeated_nested_message[0].bb)
@@ -501,7 +505,7 @@ def ExpectAllFieldsSet(test_case, message):
   test_case.assertEqual(312, message.repeated_double[1])
   test_case.assertEqual(False, message.repeated_bool[1])
   test_case.assertEqual('315', message.repeated_string[1])
-  test_case.assertEqual('316', message.repeated_bytes[1])
+  test_case.assertEqual(b'316', message.repeated_bytes[1])
 
   test_case.assertEqual(317, message.repeatedgroup[1].a)
   test_case.assertEqual(318, message.repeated_nested_message[1].bb)
@@ -552,7 +556,7 @@ def ExpectAllFieldsSet(test_case, message):
   test_case.assertEqual(412, message.default_double)
   test_case.assertEqual(False, message.default_bool)
   test_case.assertEqual('415', message.default_string)
-  test_case.assertEqual('416', message.default_bytes)
+  test_case.assertEqual(b'416', message.default_bytes)
 
   test_case.assertEqual(unittest_pb2.TestAllTypes.FOO,
                         message.default_nested_enum)
@@ -561,6 +565,7 @@ def ExpectAllFieldsSet(test_case, message):
   test_case.assertEqual(unittest_import_pb2.IMPORT_FOO,
                         message.default_import_enum)
 
+
 def GoldenFile(filename):
   """Finds the given golden file and returns a file object representing it."""
 
@@ -574,9 +579,15 @@ def GoldenFile(filename):
     path = os.path.join(path, '..')
 
   raise RuntimeError(
-    'Could not find golden files.  This test must be run from within the '
-    'protobuf source package so that it can read test data files from the '
-    'C++ source tree.')
+      'Could not find golden files.  This test must be run from within the '
+      'protobuf source package so that it can read test data files from the '
+      'C++ source tree.')
+
+
+def GoldenFileData(filename):
+  """Finds the given golden file and returns its contents."""
+  with GoldenFile(filename) as f:
+    return f.read()
 
 
 def SetAllPackedFields(message):
diff --git a/python/google/protobuf/internal/text_encoding_test.py b/python/google/protobuf/internal/text_encoding_test.py
new file mode 100755
index 00000000..ba0e45d6
--- /dev/null
+++ b/python/google/protobuf/internal/text_encoding_test.py
@@ -0,0 +1,68 @@
+#! /usr/bin/python
+#
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.  All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Tests for google.protobuf.text_encoding."""
+
+from google.apputils import basetest
+from google.protobuf import text_encoding
+
+TEST_VALUES = [
+    ("foo\\rbar\\nbaz\\t",
+     "foo\\rbar\\nbaz\\t",
+     b"foo\rbar\nbaz\t"),
+    ("\\'full of \\\"sound\\\" and \\\"fury\\\"\\'",
+     "\\'full of \\\"sound\\\" and \\\"fury\\\"\\'",
+     b"'full of \"sound\" and \"fury\"'"),
+    ("signi\\\\fying\\\\ nothing\\\\",
+     "signi\\\\fying\\\\ nothing\\\\",
+     b"signi\\fying\\ nothing\\"),
+    ("\\010\\t\\n\\013\\014\\r",
+     "\x08\\t\\n\x0b\x0c\\r",
+     b"\010\011\012\013\014\015")]
+
+
+class TextEncodingTestCase(basetest.TestCase):
+  def testCEscape(self):
+    for escaped, escaped_utf8, unescaped in TEST_VALUES:
+      self.assertEquals(escaped,
+                        text_encoding.CEscape(unescaped, as_utf8=False))
+      self.assertEquals(escaped_utf8,
+                        text_encoding.CEscape(unescaped, as_utf8=True))
+
+  def testCUnescape(self):
+    for escaped, escaped_utf8, unescaped in TEST_VALUES:
+      self.assertEquals(unescaped, text_encoding.CUnescape(escaped))
+      self.assertEquals(unescaped, text_encoding.CUnescape(escaped_utf8))
+
+
+if __name__ == "__main__":
+  basetest.main()
diff --git a/python/google/protobuf/internal/text_format_test.py b/python/google/protobuf/internal/text_format_test.py
index 4b1b4f59..a85d4dd8 100755
--- a/python/google/protobuf/internal/text_format_test.py
+++ b/python/google/protobuf/internal/text_format_test.py
@@ -34,49 +34,71 @@
 
 __author__ = 'kenton@google.com (Kenton Varda)'
 
-import difflib
 import re
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import text_format
+from google.protobuf.internal import api_implementation
 from google.protobuf.internal import test_util
 from google.protobuf import unittest_pb2
 from google.protobuf import unittest_mset_pb2
 
+class TextFormatTest(basetest.TestCase):
 
-class TextFormatTest(unittest.TestCase):
   def ReadGolden(self, golden_filename):
-    f = test_util.GoldenFile(golden_filename)
-    golden_lines = f.readlines()
-    f.close()
-    return golden_lines
+    with test_util.GoldenFile(golden_filename) as f:
+      return (f.readlines() if str is bytes else  # PY3
+              [golden_line.decode('utf-8') for golden_line in f])
 
   def CompareToGoldenFile(self, text, golden_filename):
     golden_lines = self.ReadGolden(golden_filename)
-    self.CompareToGoldenLines(text, golden_lines)
+    self.assertMultiLineEqual(text, ''.join(golden_lines))
 
   def CompareToGoldenText(self, text, golden_text):
-    self.CompareToGoldenLines(text, golden_text.splitlines(1))
-
-  def CompareToGoldenLines(self, text, golden_lines):
-    actual_lines = text.splitlines(1)
-    self.assertEqual(golden_lines, actual_lines,
-      "Text doesn't match golden.  Diff:\n" +
-      ''.join(difflib.ndiff(golden_lines, actual_lines)))
+    self.assertMultiLineEqual(text, golden_text)
 
   def testPrintAllFields(self):
     message = unittest_pb2.TestAllTypes()
     test_util.SetAllFields(message)
     self.CompareToGoldenFile(
-      self.RemoveRedundantZeros(text_format.MessageToString(message)),
-      'text_format_unittest_data.txt')
+        self.RemoveRedundantZeros(text_format.MessageToString(message)),
+        'text_format_unittest_data_oneof_implemented.txt')
+
+  def testPrintInIndexOrder(self):
+    message = unittest_pb2.TestFieldOrderings()
+    message.my_string = '115'
+    message.my_int = 101
+    message.my_float = 111
+    self.CompareToGoldenText(
+        self.RemoveRedundantZeros(text_format.MessageToString(
+            message, use_index_order=True)),
+        'my_string: \"115\"\nmy_int: 101\nmy_float: 111\n')
+    self.CompareToGoldenText(
+        self.RemoveRedundantZeros(text_format.MessageToString(
+            message)), 'my_int: 101\nmy_string: \"115\"\nmy_float: 111\n')
 
   def testPrintAllExtensions(self):
     message = unittest_pb2.TestAllExtensions()
     test_util.SetAllExtensions(message)
     self.CompareToGoldenFile(
-      self.RemoveRedundantZeros(text_format.MessageToString(message)),
-      'text_format_unittest_extensions_data.txt')
+        self.RemoveRedundantZeros(text_format.MessageToString(message)),
+        'text_format_unittest_extensions_data.txt')
+
+  def testPrintAllFieldsPointy(self):
+    message = unittest_pb2.TestAllTypes()
+    test_util.SetAllFields(message)
+    self.CompareToGoldenFile(
+        self.RemoveRedundantZeros(
+            text_format.MessageToString(message, pointy_brackets=True)),
+        'text_format_unittest_data_pointy_oneof_implemented.txt')
+
+  def testPrintAllExtensionsPointy(self):
+    message = unittest_pb2.TestAllExtensions()
+    test_util.SetAllExtensions(message)
+    self.CompareToGoldenFile(
+        self.RemoveRedundantZeros(text_format.MessageToString(
+            message, pointy_brackets=True)),
+        'text_format_unittest_extensions_data_pointy.txt')
 
   def testPrintMessageSet(self):
     message = unittest_mset_pb2.TestMessageSetContainer()
@@ -84,37 +106,16 @@ class TextFormatTest(unittest.TestCase):
     ext2 = unittest_mset_pb2.TestMessageSetExtension2.message_set_extension
     message.message_set.Extensions[ext1].i = 23
     message.message_set.Extensions[ext2].str = 'foo'
-    self.CompareToGoldenText(text_format.MessageToString(message),
-      'message_set {\n'
-      '  [protobuf_unittest.TestMessageSetExtension1] {\n'
-      '    i: 23\n'
-      '  }\n'
-      '  [protobuf_unittest.TestMessageSetExtension2] {\n'
-      '    str: \"foo\"\n'
-      '  }\n'
-      '}\n')
-
-  def testPrintBadEnumValue(self):
-    message = unittest_pb2.TestAllTypes()
-    message.optional_nested_enum = 100
-    message.optional_foreign_enum = 101
-    message.optional_import_enum = 102
-    self.CompareToGoldenText(
-        text_format.MessageToString(message),
-        'optional_nested_enum: 100\n'
-        'optional_foreign_enum: 101\n'
-        'optional_import_enum: 102\n')
-
-  def testPrintBadEnumValueExtensions(self):
-    message = unittest_pb2.TestAllExtensions()
-    message.Extensions[unittest_pb2.optional_nested_enum_extension] = 100
-    message.Extensions[unittest_pb2.optional_foreign_enum_extension] = 101
-    message.Extensions[unittest_pb2.optional_import_enum_extension] = 102
     self.CompareToGoldenText(
         text_format.MessageToString(message),
-        '[protobuf_unittest.optional_nested_enum_extension]: 100\n'
-        '[protobuf_unittest.optional_foreign_enum_extension]: 101\n'
-        '[protobuf_unittest.optional_import_enum_extension]: 102\n')
+        'message_set {\n'
+        '  [protobuf_unittest.TestMessageSetExtension1] {\n'
+        '    i: 23\n'
+        '  }\n'
+        '  [protobuf_unittest.TestMessageSetExtension2] {\n'
+        '    str: \"foo\"\n'
+        '  }\n'
+        '}\n')
 
   def testPrintExotic(self):
     message = unittest_pb2.TestAllTypes()
@@ -126,20 +127,29 @@ class TextFormatTest(unittest.TestCase):
     message.repeated_string.append('\000\001\a\b\f\n\r\t\v\\\'"')
     message.repeated_string.append(u'\u00fc\ua71f')
     self.CompareToGoldenText(
-      self.RemoveRedundantZeros(text_format.MessageToString(message)),
-      'repeated_int64: -9223372036854775808\n'
-      'repeated_uint64: 18446744073709551615\n'
-      'repeated_double: 123.456\n'
-      'repeated_double: 1.23e+22\n'
-      'repeated_double: 1.23e-18\n'
-      'repeated_string: '
-        '"\\000\\001\\007\\010\\014\\n\\r\\t\\013\\\\\\\'\\""\n'
-      'repeated_string: "\\303\\274\\352\\234\\237"\n')
+        self.RemoveRedundantZeros(text_format.MessageToString(message)),
+        'repeated_int64: -9223372036854775808\n'
+        'repeated_uint64: 18446744073709551615\n'
+        'repeated_double: 123.456\n'
+        'repeated_double: 1.23e+22\n'
+        'repeated_double: 1.23e-18\n'
+        'repeated_string:'
+        ' "\\000\\001\\007\\010\\014\\n\\r\\t\\013\\\\\\\'\\""\n'
+        'repeated_string: "\\303\\274\\352\\234\\237"\n')
+
+  def testPrintExoticUnicodeSubclass(self):
+    class UnicodeSub(unicode):
+      pass
+    message = unittest_pb2.TestAllTypes()
+    message.repeated_string.append(UnicodeSub(u'\u00fc\ua71f'))
+    self.CompareToGoldenText(
+        text_format.MessageToString(message),
+        'repeated_string: "\\303\\274\\352\\234\\237"\n')
 
   def testPrintNestedMessageAsOneLine(self):
     message = unittest_pb2.TestAllTypes()
     msg = message.repeated_nested_message.add()
-    msg.bb = 42;
+    msg.bb = 42
     self.CompareToGoldenText(
         text_format.MessageToString(message, as_one_line=True),
         'repeated_nested_message { bb: 42 }')
@@ -190,16 +200,16 @@ class TextFormatTest(unittest.TestCase):
     message.repeated_string.append('\000\001\a\b\f\n\r\t\v\\\'"')
     message.repeated_string.append(u'\u00fc\ua71f')
     self.CompareToGoldenText(
-      self.RemoveRedundantZeros(
-          text_format.MessageToString(message, as_one_line=True)),
-      'repeated_int64: -9223372036854775808'
-      ' repeated_uint64: 18446744073709551615'
-      ' repeated_double: 123.456'
-      ' repeated_double: 1.23e+22'
-      ' repeated_double: 1.23e-18'
-      ' repeated_string: '
-      '"\\000\\001\\007\\010\\014\\n\\r\\t\\013\\\\\\\'\\""'
-      ' repeated_string: "\\303\\274\\352\\234\\237"')
+        self.RemoveRedundantZeros(
+            text_format.MessageToString(message, as_one_line=True)),
+        'repeated_int64: -9223372036854775808'
+        ' repeated_uint64: 18446744073709551615'
+        ' repeated_double: 123.456'
+        ' repeated_double: 1.23e+22'
+        ' repeated_double: 1.23e-18'
+        ' repeated_string: '
+        '"\\000\\001\\007\\010\\014\\n\\r\\t\\013\\\\\\\'\\""'
+        ' repeated_string: "\\303\\274\\352\\234\\237"')
 
   def testRoundTripExoticAsOneLine(self):
     message = unittest_pb2.TestAllTypes()
@@ -215,24 +225,60 @@ class TextFormatTest(unittest.TestCase):
     wire_text = text_format.MessageToString(
         message, as_one_line=True, as_utf8=False)
     parsed_message = unittest_pb2.TestAllTypes()
-    text_format.Merge(wire_text, parsed_message)
+    r = text_format.Parse(wire_text, parsed_message)
+    self.assertIs(r, parsed_message)
     self.assertEquals(message, parsed_message)
 
     # Test as_utf8 = True.
     wire_text = text_format.MessageToString(
         message, as_one_line=True, as_utf8=True)
     parsed_message = unittest_pb2.TestAllTypes()
-    text_format.Merge(wire_text, parsed_message)
-    self.assertEquals(message, parsed_message)
+    r = text_format.Parse(wire_text, parsed_message)
+    self.assertIs(r, parsed_message)
+    self.assertEquals(message, parsed_message,
+                      '\n%s != %s' % (message, parsed_message))
 
   def testPrintRawUtf8String(self):
     message = unittest_pb2.TestAllTypes()
     message.repeated_string.append(u'\u00fc\ua71f')
-    text = text_format.MessageToString(message, as_utf8 = True)
+    text = text_format.MessageToString(message, as_utf8=True)
     self.CompareToGoldenText(text, 'repeated_string: "\303\274\352\234\237"\n')
     parsed_message = unittest_pb2.TestAllTypes()
-    text_format.Merge(text, parsed_message)
-    self.assertEquals(message, parsed_message)
+    text_format.Parse(text, parsed_message)
+    self.assertEquals(message, parsed_message,
+                      '\n%s != %s' % (message, parsed_message))
+
+  def testPrintFloatFormat(self):
+    # Check that float_format argument is passed to sub-message formatting.
+    message = unittest_pb2.NestedTestAllTypes()
+    # We use 1.25 as it is a round number in binary.  The proto 32-bit float
+    # will not gain additional imprecise digits as a 64-bit Python float and
+    # show up in its str.  32-bit 1.2 is noisy when extended to 64-bit:
+    #  >>> struct.unpack('f', struct.pack('f', 1.2))[0]
+    #  1.2000000476837158
+    #  >>> struct.unpack('f', struct.pack('f', 1.25))[0]
+    #  1.25
+    message.payload.optional_float = 1.25
+    # Check rounding at 15 significant digits
+    message.payload.optional_double = -.000003456789012345678
+    # Check no decimal point.
+    message.payload.repeated_float.append(-5642)
+    # Check no trailing zeros.
+    message.payload.repeated_double.append(.000078900)
+    formatted_fields = ['optional_float: 1.25',
+                        'optional_double: -3.45678901234568e-6',
+                        'repeated_float: -5642',
+                        'repeated_double: 7.89e-5']
+    text_message = text_format.MessageToString(message, float_format='.15g')
+    self.CompareToGoldenText(
+        self.RemoveRedundantZeros(text_message),
+        'payload {{\n  {}\n  {}\n  {}\n  {}\n}}\n'.format(*formatted_fields))
+    # as_one_line=True is a separate code branch where float_format is passed.
+    text_message = text_format.MessageToString(message, as_one_line=True,
+                                               float_format='.15g')
+    self.CompareToGoldenText(
+        self.RemoveRedundantZeros(text_message),
+        'payload {{ {} {} {} {} }}'.format(*formatted_fields))
 
   def testMessageToString(self):
     message = unittest_pb2.ForeignMessage()
@@ -249,49 +295,50 @@ class TextFormatTest(unittest.TestCase):
     text = re.compile('\.0$', re.MULTILINE).sub('', text)
     return text
 
-  def testMergeGolden(self):
+  def testParseGolden(self):
     golden_text = '\n'.join(self.ReadGolden('text_format_unittest_data.txt'))
     parsed_message = unittest_pb2.TestAllTypes()
-    text_format.Merge(golden_text, parsed_message)
+    r = text_format.Parse(golden_text, parsed_message)
+    self.assertIs(r, parsed_message)
 
     message = unittest_pb2.TestAllTypes()
     test_util.SetAllFields(message)
     self.assertEquals(message, parsed_message)
 
-  def testMergeGoldenExtensions(self):
+  def testParseGoldenExtensions(self):
     golden_text = '\n'.join(self.ReadGolden(
         'text_format_unittest_extensions_data.txt'))
     parsed_message = unittest_pb2.TestAllExtensions()
-    text_format.Merge(golden_text, parsed_message)
+    text_format.Parse(golden_text, parsed_message)
 
     message = unittest_pb2.TestAllExtensions()
     test_util.SetAllExtensions(message)
     self.assertEquals(message, parsed_message)
 
-  def testMergeAllFields(self):
+  def testParseAllFields(self):
     message = unittest_pb2.TestAllTypes()
     test_util.SetAllFields(message)
     ascii_text = text_format.MessageToString(message)
 
     parsed_message = unittest_pb2.TestAllTypes()
-    text_format.Merge(ascii_text, parsed_message)
+    text_format.Parse(ascii_text, parsed_message)
     self.assertEqual(message, parsed_message)
     test_util.ExpectAllFieldsSet(self, message)
 
-  def testMergeAllExtensions(self):
+  def testParseAllExtensions(self):
     message = unittest_pb2.TestAllExtensions()
     test_util.SetAllExtensions(message)
     ascii_text = text_format.MessageToString(message)
 
     parsed_message = unittest_pb2.TestAllExtensions()
-    text_format.Merge(ascii_text, parsed_message)
+    text_format.Parse(ascii_text, parsed_message)
     self.assertEqual(message, parsed_message)
 
-  def testMergeMessageSet(self):
+  def testParseMessageSet(self):
     message = unittest_pb2.TestAllTypes()
     text = ('repeated_uint64: 1\n'
             'repeated_uint64: 2\n')
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
     self.assertEqual(1, message.repeated_uint64[0])
     self.assertEqual(2, message.repeated_uint64[1])
 
@@ -304,13 +351,13 @@ class TextFormatTest(unittest.TestCase):
             '    str: \"foo\"\n'
             '  }\n'
             '}\n')
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
     ext1 = unittest_mset_pb2.TestMessageSetExtension1.message_set_extension
     ext2 = unittest_mset_pb2.TestMessageSetExtension2.message_set_extension
     self.assertEquals(23, message.message_set.Extensions[ext1].i)
     self.assertEquals('foo', message.message_set.Extensions[ext2].str)
 
-  def testMergeExotic(self):
+  def testParseExotic(self):
     message = unittest_pb2.TestAllTypes()
     text = ('repeated_int64: -9223372036854775808\n'
             'repeated_uint64: 18446744073709551615\n'
@@ -323,7 +370,7 @@ class TextFormatTest(unittest.TestCase):
             'repeated_string: "\\303\\274\\352\\234\\237"\n'
             'repeated_string: "\\xc3\\xbc"\n'
             'repeated_string: "\xc3\xbc"\n')
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
 
     self.assertEqual(-9223372036854775808, message.repeated_int64[0])
     self.assertEqual(18446744073709551615, message.repeated_uint64[0])
@@ -336,100 +383,115 @@ class TextFormatTest(unittest.TestCase):
     self.assertEqual(u'\u00fc\ua71f', message.repeated_string[2])
     self.assertEqual(u'\u00fc', message.repeated_string[3])
 
-  def testMergeEmptyText(self):
+  def testParseTrailingCommas(self):
+    message = unittest_pb2.TestAllTypes()
+    text = ('repeated_int64: 100;\n'
+            'repeated_int64: 200;\n'
+            'repeated_int64: 300,\n'
+            'repeated_string: "one",\n'
+            'repeated_string: "two";\n')
+    text_format.Parse(text, message)
+
+    self.assertEqual(100, message.repeated_int64[0])
+    self.assertEqual(200, message.repeated_int64[1])
+    self.assertEqual(300, message.repeated_int64[2])
+    self.assertEqual(u'one', message.repeated_string[0])
+    self.assertEqual(u'two', message.repeated_string[1])
+
+  def testParseEmptyText(self):
     message = unittest_pb2.TestAllTypes()
     text = ''
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
     self.assertEquals(unittest_pb2.TestAllTypes(), message)
 
-  def testMergeInvalidUtf8(self):
+  def testParseInvalidUtf8(self):
     message = unittest_pb2.TestAllTypes()
     text = 'repeated_string: "\\xc3\\xc3"'
-    self.assertRaises(text_format.ParseError, text_format.Merge, text, message)
+    self.assertRaises(text_format.ParseError, text_format.Parse, text, message)
 
-  def testMergeSingleWord(self):
+  def testParseSingleWord(self):
     message = unittest_pb2.TestAllTypes()
     text = 'foo'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         ('1:1 : Message type "protobuf_unittest.TestAllTypes" has no field named '
          '"foo".'),
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
-  def testMergeUnknownField(self):
+  def testParseUnknownField(self):
     message = unittest_pb2.TestAllTypes()
     text = 'unknown_field: 8\n'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         ('1:1 : Message type "protobuf_unittest.TestAllTypes" has no field named '
          '"unknown_field".'),
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
-  def testMergeBadExtension(self):
+  def testParseBadExtension(self):
     message = unittest_pb2.TestAllExtensions()
     text = '[unknown_extension]: 8\n'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         '1:2 : Extension "unknown_extension" not registered.',
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
     message = unittest_pb2.TestAllTypes()
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         ('1:2 : Message type "protobuf_unittest.TestAllTypes" does not have '
          'extensions.'),
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
-  def testMergeGroupNotClosed(self):
+  def testParseGroupNotClosed(self):
     message = unittest_pb2.TestAllTypes()
     text = 'RepeatedGroup: <'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError, '1:16 : Expected ">".',
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
     text = 'RepeatedGroup: {'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError, '1:16 : Expected "}".',
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
-  def testMergeEmptyGroup(self):
+  def testParseEmptyGroup(self):
     message = unittest_pb2.TestAllTypes()
     text = 'OptionalGroup: {}'
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
     self.assertTrue(message.HasField('optionalgroup'))
 
     message.Clear()
 
     message = unittest_pb2.TestAllTypes()
     text = 'OptionalGroup: <>'
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
     self.assertTrue(message.HasField('optionalgroup'))
 
-  def testMergeBadEnumValue(self):
+  def testParseBadEnumValue(self):
     message = unittest_pb2.TestAllTypes()
     text = 'optional_nested_enum: BARR'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         ('1:23 : Enum type "protobuf_unittest.TestAllTypes.NestedEnum" '
          'has no value named BARR.'),
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
     message = unittest_pb2.TestAllTypes()
     text = 'optional_nested_enum: 100'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         ('1:23 : Enum type "protobuf_unittest.TestAllTypes.NestedEnum" '
          'has no value with number 100.'),
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
-  def testMergeBadIntValue(self):
+  def testParseBadIntValue(self):
     message = unittest_pb2.TestAllTypes()
     text = 'optional_int32: bork'
-    self.assertRaisesWithMessage(
+    self.assertRaisesWithLiteralMatch(
         text_format.ParseError,
         ('1:17 : Couldn\'t parse integer: bork'),
-        text_format.Merge, text, message)
+        text_format.Parse, text, message)
 
-  def testMergeStringFieldUnescape(self):
+  def testParseStringFieldUnescape(self):
     message = unittest_pb2.TestAllTypes()
     text = r'''repeated_string: "\xf\x62"
                repeated_string: "\\xf\\x62"
@@ -437,7 +499,7 @@ class TextFormatTest(unittest.TestCase):
                repeated_string: "\\\\xf\\\\x62"
                repeated_string: "\\\\\xf\\\\\x62"
                repeated_string: "\x5cx20"'''
-    text_format.Merge(text, message)
+    text_format.Parse(text, message)
 
     SLASH = '\\'
     self.assertEqual('\x0fb', message.repeated_string[0])
@@ -449,27 +511,84 @@ class TextFormatTest(unittest.TestCase):
                      message.repeated_string[4])
     self.assertEqual(SLASH + 'x20', message.repeated_string[5])
 
-  def assertRaisesWithMessage(self, e_class, e, func, *args, **kwargs):
-    """Same as assertRaises, but also compares the exception message."""
-    if hasattr(e_class, '__name__'):
-      exc_name = e_class.__name__
-    else:
-      exc_name = str(e_class)
+  def testMergeRepeatedScalars(self):
+    message = unittest_pb2.TestAllTypes()
+    text = ('optional_int32: 42 '
+            'optional_int32: 67')
+    r = text_format.Merge(text, message)
+    self.assertIs(r, message)
+    self.assertEqual(67, message.optional_int32)
+
+  def testParseRepeatedScalars(self):
+    message = unittest_pb2.TestAllTypes()
+    text = ('optional_int32: 42 '
+            'optional_int32: 67')
+    self.assertRaisesWithLiteralMatch(
+        text_format.ParseError,
+        ('1:36 : Message type "protobuf_unittest.TestAllTypes" should not '
+         'have multiple "optional_int32" fields.'),
+        text_format.Parse, text, message)
+
+  def testMergeRepeatedNestedMessageScalars(self):
+    message = unittest_pb2.TestAllTypes()
+    text = ('optional_nested_message { bb: 1 } '
+            'optional_nested_message { bb: 2 }')
+    r = text_format.Merge(text, message)
+    self.assertTrue(r is message)
+    self.assertEqual(2, message.optional_nested_message.bb)
+
+  def testParseRepeatedNestedMessageScalars(self):
+    message = unittest_pb2.TestAllTypes()
+    text = ('optional_nested_message { bb: 1 } '
+            'optional_nested_message { bb: 2 }')
+    self.assertRaisesWithLiteralMatch(
+        text_format.ParseError,
+        ('1:65 : Message type "protobuf_unittest.TestAllTypes.NestedMessage" '
+         'should not have multiple "bb" fields.'),
+        text_format.Parse, text, message)
+
+  def testMergeRepeatedExtensionScalars(self):
+    message = unittest_pb2.TestAllExtensions()
+    text = ('[protobuf_unittest.optional_int32_extension]: 42 '
+            '[protobuf_unittest.optional_int32_extension]: 67')
+    text_format.Merge(text, message)
+    self.assertEqual(
+        67,
+        message.Extensions[unittest_pb2.optional_int32_extension])
+
+  def testParseRepeatedExtensionScalars(self):
+    message = unittest_pb2.TestAllExtensions()
+    text = ('[protobuf_unittest.optional_int32_extension]: 42 '
+            '[protobuf_unittest.optional_int32_extension]: 67')
+    self.assertRaisesWithLiteralMatch(
+        text_format.ParseError,
+        ('1:96 : Message type "protobuf_unittest.TestAllExtensions" '
+         'should not have multiple '
+         '"protobuf_unittest.optional_int32_extension" extensions.'),
+        text_format.Parse, text, message)
+
+  def testParseLinesGolden(self):
+    opened = self.ReadGolden('text_format_unittest_data.txt')
+    parsed_message = unittest_pb2.TestAllTypes()
+    r = text_format.ParseLines(opened, parsed_message)
+    self.assertIs(r, parsed_message)
+
+    message = unittest_pb2.TestAllTypes()
+    test_util.SetAllFields(message)
+    self.assertEquals(message, parsed_message)
+
+  def testMergeLinesGolden(self):
+    opened = self.ReadGolden('text_format_unittest_data.txt')
+    parsed_message = unittest_pb2.TestAllTypes()
+    r = text_format.MergeLines(opened, parsed_message)
+    self.assertIs(r, parsed_message)
 
-    try:
-      func(*args, **kwargs)
-    except e_class as expr:
-      if str(expr) != e:
-        msg = '%s raised, but with wrong message: "%s" instead of "%s"'
-        raise self.failureException(msg % (exc_name,
-                                           str(expr).encode('string_escape'),
-                                           e.encode('string_escape')))
-      return
-    else:
-      raise self.failureException('%s not raised' % exc_name)
+    message = unittest_pb2.TestAllTypes()
+    test_util.SetAllFields(message)
+    self.assertEqual(message, parsed_message)
 
 
-class TokenizerTest(unittest.TestCase):
+class TokenizerTest(basetest.TestCase):
 
   def testSimpleTokenCases(self):
     text = ('identifier1:"string1"\n     \n\n'
@@ -478,8 +597,8 @@ class TokenizerTest(unittest.TestCase):
             'ID7 : "aa\\"bb"\n\n\n\n ID8: {A:inf B:-inf C:true D:false}\n'
             'ID9: 22 ID10: -111111111111111111 ID11: -22\n'
             'ID12: 2222222222222222222 ID13: 1.23456f ID14: 1.2e+2f '
-            'false_bool:  0 true_BOOL:t \n true_bool1:  1 false_BOOL1:f ' )
-    tokenizer = text_format._Tokenizer(text)
+            'false_bool:  0 true_BOOL:t \n true_bool1:  1 false_BOOL1:f ')
+    tokenizer = text_format._Tokenizer(text.splitlines())
     methods = [(tokenizer.ConsumeIdentifier, 'identifier1'),
                ':',
                (tokenizer.ConsumeString, 'string1'),
@@ -565,7 +684,7 @@ class TokenizerTest(unittest.TestCase):
     int64_max = (1 << 63) - 1
     uint32_max = (1 << 32) - 1
     text = '-1 %d %d' % (uint32_max + 1, int64_max + 1)
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeUint32)
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeUint64)
     self.assertEqual(-1, tokenizer.ConsumeInt32())
@@ -579,7 +698,7 @@ class TokenizerTest(unittest.TestCase):
     self.assertTrue(tokenizer.AtEnd())
 
     text = '-0 -0 0 0'
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertEqual(0, tokenizer.ConsumeUint32())
     self.assertEqual(0, tokenizer.ConsumeUint64())
     self.assertEqual(0, tokenizer.ConsumeUint32())
@@ -588,30 +707,30 @@ class TokenizerTest(unittest.TestCase):
 
   def testConsumeByteString(self):
     text = '"string1\''
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeByteString)
 
     text = 'string1"'
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeByteString)
 
     text = '\n"\\xt"'
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeByteString)
 
     text = '\n"\\"'
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeByteString)
 
     text = '\n"\\x"'
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeByteString)
 
   def testConsumeBool(self):
     text = 'not-a-bool'
-    tokenizer = text_format._Tokenizer(text)
+    tokenizer = text_format._Tokenizer(text.splitlines())
     self.assertRaises(text_format.ParseError, tokenizer.ConsumeBool)
 
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/type_checkers.py b/python/google/protobuf/internal/type_checkers.py
index 2b3cd4de..8e1b3cc3 100755
--- a/python/google/protobuf/internal/type_checkers.py
+++ b/python/google/protobuf/internal/type_checkers.py
@@ -28,6 +28,10 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#PY25 compatible for GAE.
+#
+# Copyright 2008 Google Inc. All Rights Reserved.
+
 """Provides type checking routines.
 
 This module defines type checking utilities in the forms of dictionaries:
@@ -45,6 +49,9 @@ TYPE_TO_DESERIALIZE_METHOD: A dictionary with field types and deserialization
 
 __author__ = 'robinson@google.com (Will Robinson)'
 
+import sys  ##PY25
+if sys.version < '2.6': bytes = str  ##PY25
+from google.protobuf.internal import api_implementation
 from google.protobuf.internal import decoder
 from google.protobuf.internal import encoder
 from google.protobuf.internal import wire_format
@@ -53,21 +60,22 @@ from google.protobuf import descriptor
 _FieldDescriptor = descriptor.FieldDescriptor
 
 
-def GetTypeChecker(cpp_type, field_type):
+def GetTypeChecker(field):
   """Returns a type checker for a message field of the specified types.
 
   Args:
-    cpp_type: C++ type of the field (see descriptor.py).
-    field_type: Protocol message field type (see descriptor.py).
+    field: FieldDescriptor object for this field.
 
   Returns:
     An instance of TypeChecker which can be used to verify the types
     of values assigned to a field of the specified type.
   """
-  if (cpp_type == _FieldDescriptor.CPPTYPE_STRING and
-      field_type == _FieldDescriptor.TYPE_STRING):
+  if (field.cpp_type == _FieldDescriptor.CPPTYPE_STRING and
+      field.type == _FieldDescriptor.TYPE_STRING):
     return UnicodeValueChecker()
-  return _VALUE_CHECKERS[cpp_type]
+  if field.cpp_type == _FieldDescriptor.CPPTYPE_ENUM:
+    return EnumValueChecker(field.enum_type)
+  return _VALUE_CHECKERS[field.cpp_type]
 
 
 # None of the typecheckers below make any attempt to guard against people
@@ -85,10 +93,15 @@ class TypeChecker(object):
     self._acceptable_types = acceptable_types
 
   def CheckValue(self, proposed_value):
+    """Type check the provided value and return it.
+
+    The returned value might have been normalized to another type.
+    """
     if not isinstance(proposed_value, self._acceptable_types):
       message = ('%.1024r has type %s, but expected one of: %s' %
                  (proposed_value, type(proposed_value), self._acceptable_types))
       raise TypeError(message)
+    return proposed_value
 
 
 # IntValueChecker and its subclasses perform integer type-checks
@@ -104,28 +117,54 @@ class IntValueChecker(object):
       raise TypeError(message)
     if not self._MIN <= proposed_value <= self._MAX:
       raise ValueError('Value out of range: %d' % proposed_value)
+    # We force 32-bit values to int and 64-bit values to long to make
+    # alternate implementations where the distinction is more significant
+    # (e.g. the C++ implementation) simpler.
+    proposed_value = self._TYPE(proposed_value)
+    return proposed_value
+
+
+class EnumValueChecker(object):
+
+  """Checker used for enum fields.  Performs type-check and range check."""
+
+  def __init__(self, enum_type):
+    self._enum_type = enum_type
+
+  def CheckValue(self, proposed_value):
+    if not isinstance(proposed_value, (int, long)):
+      message = ('%.1024r has type %s, but expected one of: %s' %
+                 (proposed_value, type(proposed_value), (int, long)))
+      raise TypeError(message)
+    if proposed_value not in self._enum_type.values_by_number:
+      raise ValueError('Unknown enum value: %d' % proposed_value)
+    return proposed_value
 
 
 class UnicodeValueChecker(object):
 
-  """Checker used for string fields."""
+  """Checker used for string fields.
+
+  Always returns a unicode value, even if the input is of type str.
+  """
 
   def CheckValue(self, proposed_value):
-    if not isinstance(proposed_value, (str, unicode)):
+    if not isinstance(proposed_value, (bytes, unicode)):
       message = ('%.1024r has type %s, but expected one of: %s' %
-                 (proposed_value, type(proposed_value), (str, unicode)))
+                 (proposed_value, type(proposed_value), (bytes, unicode)))
       raise TypeError(message)
 
-    # If the value is of type 'str' make sure that it is in 7-bit ASCII
+    # If the value is of type 'bytes' make sure that it is in 7-bit ASCII
     # encoding.
-    if isinstance(proposed_value, str):
+    if isinstance(proposed_value, bytes):
       try:
-        unicode(proposed_value, 'ascii')
+        proposed_value = proposed_value.decode('ascii')
       except UnicodeDecodeError:
-        raise ValueError('%.1024r has type str, but isn\'t in 7-bit ASCII '
+        raise ValueError('%.1024r has type bytes, but isn\'t in 7-bit ASCII '
                          'encoding. Non-ASCII strings must be converted to '
                          'unicode objects before being added.' %
                          (proposed_value))
+    return proposed_value
 
 
 class Int32ValueChecker(IntValueChecker):
@@ -133,21 +172,25 @@ class Int32ValueChecker(IntValueChecker):
   # efficient.
   _MIN = -2147483648
   _MAX = 2147483647
+  _TYPE = int
 
 
 class Uint32ValueChecker(IntValueChecker):
   _MIN = 0
   _MAX = (1 << 32) - 1
+  _TYPE = int
 
 
 class Int64ValueChecker(IntValueChecker):
   _MIN = -(1 << 63)
   _MAX = (1 << 63) - 1
+  _TYPE = long
 
 
 class Uint64ValueChecker(IntValueChecker):
   _MIN = 0
   _MAX = (1 << 64) - 1
+  _TYPE = long
 
 
 # Type-checkers for all scalar CPPTYPEs.
@@ -161,8 +204,7 @@ _VALUE_CHECKERS = {
     _FieldDescriptor.CPPTYPE_FLOAT: TypeChecker(
         float, int, long),
     _FieldDescriptor.CPPTYPE_BOOL: TypeChecker(bool, int),
-    _FieldDescriptor.CPPTYPE_ENUM: Int32ValueChecker(),
-    _FieldDescriptor.CPPTYPE_STRING: TypeChecker(str),
+    _FieldDescriptor.CPPTYPE_STRING: TypeChecker(bytes),
     }
 
 
diff --git a/python/google/protobuf/internal/unknown_fields_test.py b/python/google/protobuf/internal/unknown_fields_test.py
index 84984b40..8f3354c9 100755
--- a/python/google/protobuf/internal/unknown_fields_test.py
+++ b/python/google/protobuf/internal/unknown_fields_test.py
@@ -35,15 +35,16 @@
 
 __author__ = 'bohdank@google.com (Bohdan Koval)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import unittest_mset_pb2
 from google.protobuf import unittest_pb2
 from google.protobuf.internal import encoder
+from google.protobuf.internal import missing_enum_values_pb2
 from google.protobuf.internal import test_util
 from google.protobuf.internal import type_checkers
 
 
-class UnknownFieldsTest(unittest.TestCase):
+class UnknownFieldsTest(basetest.TestCase):
 
   def setUp(self):
     self.descriptor = unittest_pb2.TestAllTypes.DESCRIPTOR
@@ -58,12 +59,20 @@ class UnknownFieldsTest(unittest.TestCase):
     field_descriptor = self.descriptor.fields_by_name[name]
     wire_type = type_checkers.FIELD_TYPE_TO_WIRE_TYPE[field_descriptor.type]
     field_tag = encoder.TagBytes(field_descriptor.number, wire_type)
+    result_dict = {}
     for tag_bytes, value in self.unknown_fields:
       if tag_bytes == field_tag:
         decoder = unittest_pb2.TestAllTypes._decoders_by_tag[tag_bytes]
-        result_dict = {}
         decoder(value, 0, len(value), self.all_fields, result_dict)
-        return result_dict[field_descriptor]
+    return result_dict[field_descriptor]
+
+  def testEnum(self):
+    value = self.GetField('optional_nested_enum')
+    self.assertEqual(self.all_fields.optional_nested_enum, value)
+
+  def testRepeatedEnum(self):
+    value = self.GetField('repeated_nested_enum')
+    self.assertEqual(self.all_fields.repeated_nested_enum, value)
 
   def testVarint(self):
     value = self.GetField('optional_int32')
@@ -166,5 +175,57 @@ class UnknownFieldsTest(unittest.TestCase):
     self.assertNotEqual(self.empty_message, message)
 
 
+class UnknownFieldsTest(basetest.TestCase):
+
+  def setUp(self):
+    self.descriptor = missing_enum_values_pb2.TestEnumValues.DESCRIPTOR
+
+    self.message = missing_enum_values_pb2.TestEnumValues()
+    self.message.optional_nested_enum = (
+      missing_enum_values_pb2.TestEnumValues.ZERO)
+    self.message.repeated_nested_enum.extend([
+      missing_enum_values_pb2.TestEnumValues.ZERO,
+      missing_enum_values_pb2.TestEnumValues.ONE,
+      ])
+    self.message.packed_nested_enum.extend([
+      missing_enum_values_pb2.TestEnumValues.ZERO,
+      missing_enum_values_pb2.TestEnumValues.ONE,
+      ])
+    self.message_data = self.message.SerializeToString()
+    self.missing_message = missing_enum_values_pb2.TestMissingEnumValues()
+    self.missing_message.ParseFromString(self.message_data)
+    self.unknown_fields = self.missing_message._unknown_fields
+
+  def GetField(self, name):
+    field_descriptor = self.descriptor.fields_by_name[name]
+    wire_type = type_checkers.FIELD_TYPE_TO_WIRE_TYPE[field_descriptor.type]
+    field_tag = encoder.TagBytes(field_descriptor.number, wire_type)
+    result_dict = {}
+    for tag_bytes, value in self.unknown_fields:
+      if tag_bytes == field_tag:
+        decoder = missing_enum_values_pb2.TestEnumValues._decoders_by_tag[
+          tag_bytes]
+        decoder(value, 0, len(value), self.message, result_dict)
+    return result_dict[field_descriptor]
+
+  def testUnknownEnumValue(self):
+    self.assertFalse(self.missing_message.HasField('optional_nested_enum'))
+    value = self.GetField('optional_nested_enum')
+    self.assertEqual(self.message.optional_nested_enum, value)
+
+  def testUnknownRepeatedEnumValue(self):
+    value = self.GetField('repeated_nested_enum')
+    self.assertEqual(self.message.repeated_nested_enum, value)
+
+  def testUnknownPackedEnumValue(self):
+    value = self.GetField('packed_nested_enum')
+    self.assertEqual(self.message.packed_nested_enum, value)
+
+  def testRoundTrip(self):
+    new_message = missing_enum_values_pb2.TestEnumValues()
+    new_message.ParseFromString(self.missing_message.SerializeToString())
+    self.assertEqual(self.message, new_message)
+
+
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()
diff --git a/python/google/protobuf/internal/wire_format_test.py b/python/google/protobuf/internal/wire_format_test.py
index 76007786..9362c72d 100755
--- a/python/google/protobuf/internal/wire_format_test.py
+++ b/python/google/protobuf/internal/wire_format_test.py
@@ -34,12 +34,12 @@
 
 __author__ = 'robinson@google.com (Will Robinson)'
 
-import unittest
+from google.apputils import basetest
 from google.protobuf import message
 from google.protobuf.internal import wire_format
 
 
-class WireFormatTest(unittest.TestCase):
+class WireFormatTest(basetest.TestCase):
 
   def testPackTag(self):
     field_number = 0xabc
@@ -195,7 +195,7 @@ class WireFormatTest(unittest.TestCase):
     # Test UTF-8 string byte size calculation.
     # 1 byte for tag, 1 byte for length, 8 bytes for content.
     self.assertEqual(10, wire_format.StringByteSize(
-        5, unicode('\xd0\xa2\xd0\xb5\xd1\x81\xd1\x82', 'utf-8')))
+        5, b'\xd0\xa2\xd0\xb5\xd1\x81\xd1\x82'.decode('utf-8')))
 
     class MockMessage(object):
       def __init__(self, byte_size):
@@ -250,4 +250,4 @@ class WireFormatTest(unittest.TestCase):
 
 
 if __name__ == '__main__':
-  unittest.main()
+  basetest.main()