PYTHON-5395 - Investigate why we don't encode Python decimal instances by default

Author: NoahStapp

bson/__init__.py

@@ -72,6 +72,7 @@
 from __future__ import annotations
 
 import datetime
+import decimal
 import itertools
 import os
 import re
@@ -858,6 +859,11 @@ def _encode_decimal128(name: bytes, value: Decimal128, dummy0: Any, dummy1: Any)
     return b"\x13" + name + value.bid
 
 
+def _encode_python_decimal(name: bytes, value: decimal.Decimal, dummy0: Any, dummy1: Any) -> bytes:
+    converted = Decimal128(value)
+    return b"\x13" + name + converted.bid
+
+
 def _encode_minkey(name: bytes, dummy0: Any, dummy1: Any, dummy2: Any) -> bytes:
     """Encode bson.min_key.MinKey."""
     return b"\xFF" + name
@@ -885,6 +891,7 @@ def _encode_maxkey(name: bytes, dummy0: Any, dummy1: Any, dummy2: Any) -> bytes:
     str: _encode_text,
     tuple: _encode_list,
     type(None): _encode_none,
+    decimal.Decimal: _encode_python_decimal,
     uuid.UUID: _encode_uuid,
     Binary: _encode_binary,
     Int64: _encode_long,