fix #3463 by explicitly failing if no stoploss is defined

tests/pairlist/test_pairlist.py

@@ -362,6 +362,17 @@ def test_VolumePairList_whitelist_gen(mocker, whitelist_conf, shitcoinmarkets, t
                     assert not log_has(logmsg, caplog)
 
 
+def test_PrecisionFilter_error(mocker, whitelist_conf, tickers) -> None:
+    whitelist_conf['pairlists'] = [{"method": "StaticPairList"}, {"method": "PrecisionFilter"}]
+    del whitelist_conf['stoploss']
+
+    mocker.patch('freqtrade.exchange.Exchange.exchange_has', MagicMock(return_value=True))
+
+    with pytest.raises(OperationalException,
+                       match=r"PrecisionFilter can only work with stoploss defined\..*"):
+        PairListManager(MagicMock, whitelist_conf)
+
+
 def test_gen_pair_whitelist_not_supported(mocker, default_conf, tickers) -> None:
     default_conf['pairlists'] = [{'method': 'VolumePairList', 'number_assets': 10}]