Improve exception wording

freqtrade/data/converter/trade_converter_kraken.py

@@ -7,6 +7,7 @@ from freqtrade.constants import DATETIME_PRINT_FORMAT, DEFAULT_TRADES_COLUMNS, C
 from freqtrade.data.converter.trade_converter import (trades_convert_types,
                                                       trades_df_remove_duplicates)
 from freqtrade.data.history.idatahandler import get_datahandler
+from freqtrade.exceptions import OperationalException
 from freqtrade.resolvers import ExchangeResolver
 
 
@@ -20,7 +21,7 @@ def import_kraken_trades_from_csv(config: Config, convert_to: str):
     Import kraken trades from csv
     """
     if config['exchange']['name'] != 'kraken':
-        raise ValueError('This function is only for kraken exchange')
+        raise OperationalException('This function is only for the kraken exchange.')
 
     datadir: Path = config['datadir']
     data_handler = get_datahandler(datadir, data_format=convert_to)

tests/data/test_trade_converter_kraken.py

@@ -3,12 +3,18 @@ from pathlib import Path
 from shutil import copytree
 from unittest.mock import PropertyMock
 
+import pytest
+
 from freqtrade.data.converter.trade_converter_kraken import import_kraken_trades_from_csv
 from freqtrade.data.history.idatahandler import get_datahandler
+from freqtrade.exceptions import OperationalException
 from tests.conftest import EXMS, log_has, log_has_re, patch_exchange
 
 
 def test_import_kraken_trades_from_csv(testdatadir, tmpdir, caplog, default_conf_usdt, mocker):
+    with pytest.raises(OperationalException, match="This function is only for the kraken exchange"):
+        import_kraken_trades_from_csv(default_conf_usdt, 'feather')
+
     default_conf_usdt['exchange']['name'] = 'kraken'
 
     patch_exchange(mocker, id='kraken')