more accurate benchmarking by adding _to_dict helper

pymongo/bson.py

@@ -364,6 +364,24 @@ def _dict_to_bson(dict):
 if _use_c:
     _dict_to_bson = _cbson._dict_to_bson
 
+def _to_dicts(data):
+    """Convert binary data to sequence of SON objects.
+
+    Data must be concatenated strings of valid BSON data.
+
+    :Parameters:
+      - `data`: bson data
+    """
+    dicts = []
+    while len(data):
+        (son, data) = _bson_to_dict(data)
+        dicts.append(son)
+    return dicts
+
+def _to_dict(data):
+    (son, _) = _bson_to_dict(data)
+    return son
+
 def is_valid(bson):
     """Validate that the given string represents valid BSON data.
 
@@ -382,20 +400,6 @@ def is_valid(bson):
     except (AssertionError, InvalidBSON):
         return False
 
-def _to_dicts(data):
-    """Convert binary data to sequence of SON objects.
-
-    Data must be concatenated strings of valid BSON data.
-
-    :Parameters:
-      - `data`: bson data
-    """
-    dicts = []
-    while len(data):
-        (son, data) = _bson_to_dict(data)
-        dicts.append(son)
-    return dicts
-
 class BSON(str):
     """BSON data.
 

tools/bson_benchmark.py

@@ -59,7 +59,7 @@ def main():
         print "enc json",
         enc_json = run(case, json.dumps)
         print "dec bson",
-        assert case == run(enc_bson, bson._to_dicts)[0]
+        assert case == run(enc_bson, bson._to_dict)
         print "dec json",
         assert case == run(enc_json, json.loads)