PYTHON-1284 Don't copy CodecOptions in RawBSONDocument

bson/codec_options.py

@@ -111,6 +111,26 @@ class CodecOptions(_options_base):
     def __repr__(self):
         return '%s(%s)' % (self.__class__.__name__, self._arguments_repr())
 
+    def with_options(self, **kwargs):
+        """Make a copy of this CodecOptions, overriding some options::
+
+        >>> from bson.codec_options import DEFAULT_CODEC_OPTIONS
+        >>> DEFAULT_CODEC_OPTIONS.tz_aware
+        False
+        >>> options = DEFAULT_CODEC_OPTIONS.with_options(tz_aware=True)
+        >>> options.tz_aware
+        True
+
+        .. versionadded:: 3.5
+        """
+        return CodecOptions(
+            kwargs.get('document_class', self.document_class),
+            kwargs.get('tz_aware', self.tz_aware),
+            kwargs.get('uuid_representation', self.uuid_representation),
+            kwargs.get('unicode_decode_error_handler',
+                       self.unicode_decode_error_handler),
+            kwargs.get('tzinfo', self.tzinfo))
+
 
 DEFAULT_CODEC_OPTIONS = CodecOptions()
 

bson/raw_bson.py

@@ -20,7 +20,7 @@ import collections
 from bson import _UNPACK_INT, _iterate_elements
 from bson.py3compat import iteritems
 from bson.codec_options import (
-    CodecOptions, DEFAULT_CODEC_OPTIONS, _RAW_BSON_DOCUMENT_MARKER)
+    CodecOptions, DEFAULT_CODEC_OPTIONS as DEFAULT, _RAW_BSON_DOCUMENT_MARKER)
 from bson.errors import InvalidBSON
 
 
@@ -35,24 +35,29 @@ class RawBSONDocument(collections.Mapping):
     __slots__ = ('__raw', '__inflated_doc', '__codec_options')
     _type_marker = _RAW_BSON_DOCUMENT_MARKER
 
-    def __init__(self, bson_bytes, codec_options=DEFAULT_CODEC_OPTIONS):
+    def __init__(self, bson_bytes, codec_options=None):
         """Create a new :class:`RawBSONDocument`.
 
         :Parameters:
           - `bson_bytes`: the BSON bytes that compose this document
           - `codec_options` (optional): An instance of
             :class:`~bson.codec_options.CodecOptions`.
+
+        .. versionchanged:: 3.5
+          If a :class:`~bson.codec_options.CodecOptions` is passed in, its
+          `document_class` must be :class:`RawBSONDocument`.
         """
         self.__raw = bson_bytes
         self.__inflated_doc = None
-        # Always decode documents to their lazy representations.
-        co = codec_options
-        self.__codec_options = CodecOptions(
-            tz_aware=co.tz_aware,
-            document_class=RawBSONDocument,
-            uuid_representation=co.uuid_representation,
-            unicode_decode_error_handler=co.unicode_decode_error_handler,
-            tzinfo=co.tzinfo)
+        # Can't default codec_options to DEFAULT_RAW_BSON_OPTIONS in signature,
+        # it refers to this class RawBSONDocument.
+        if codec_options is None:
+            codec_options = DEFAULT_RAW_BSON_OPTIONS
+        elif codec_options.document_class is not RawBSONDocument:
+            raise TypeError(
+                "RawBSONDocument cannot use CodecOptions with document "
+                "class %s" % (codec_options.document_class, ))
+        self.__codec_options = codec_options
 
     @property
     def raw(self):
@@ -96,3 +101,6 @@ class RawBSONDocument(collections.Mapping):
     def __repr__(self):
         return ("RawBSONDocument(%r, codec_options=%r)"
                 % (self.raw, self.__codec_options))
+
+
+DEFAULT_RAW_BSON_OPTIONS = DEFAULT.with_options(document_class=RawBSONDocument)

doc/changelog.rst

@@ -1,6 +1,12 @@
 Changelog
 =========
 
+Changes in Next Version
+-----------------------
+
+If a custom :class:`~bson.codec_options.CodecOptions` is passed to
+:class:`RawBSONDocument`, its `document_class` must be :class:`RawBSONDocument`.
+
 Changes in Version 3.4
 ----------------------
 

test/test_raw_bson.py

@@ -58,7 +58,8 @@ class TestRawBSONDocument(unittest.TestCase):
         )
         document = RawBSONDocument(
             bson_string,
-            codec_options=CodecOptions(uuid_representation=JAVA_LEGACY))
+            codec_options=CodecOptions(uuid_representation=JAVA_LEGACY,
+                                       document_class=RawBSONDocument))
 
         self.assertEqual(uuid.UUID('026fab8f-975f-4965-9fbf-85ad874c60ff'),
                          document['_id'])
@@ -103,7 +104,8 @@ class TestRawBSONDocument(unittest.TestCase):
         )
         rbd = RawBSONDocument(
             bson_string,
-            codec_options=CodecOptions(uuid_representation=JAVA_LEGACY))
+            codec_options=CodecOptions(uuid_representation=JAVA_LEGACY,
+                                       document_class=RawBSONDocument))
 
         db.test_raw.drop()
         db.test_raw.insert_one(rbd)