convert_datetime64 defaults to True if not passed

Author: reidy-p

pandas/core/frame.py

@@ -1384,6 +1384,8 @@ def to_records(self, index=True, convert_datetime64=None):
                           "deprecated and will be removed in a future "
                           "version",
                           FutureWarning, stacklevel=2)
+        else:
+            convert_datetime64 = True
 
         if index:
             if is_datetime64_any_dtype(self.index) and convert_datetime64:

pandas/tests/frame/test_convert_to.py

@@ -79,11 +79,17 @@ def test_to_records_dt64(self):
         df = DataFrame([["one", "two", "three"],
                         ["four", "five", "six"]],
                        index=date_range("2012-01-01", "2012-01-02"))
+
         with tm.assert_produces_warning(FutureWarning):
             expected = df.index[0]
             result = df.to_records(convert_datetime64=True)['index'][0]
             assert expected == result
 
+        expected = df.index[0]
+        # convert_datetime64 defaults to True if not passed
+        result = df.to_records()['index'][0]
+        assert expected == result
+
         with tm.assert_produces_warning(FutureWarning):
             rs = df.to_records(convert_datetime64=False)
             assert rs['index'][0] == df.index.values[0]