add ohlcv_has_history - disabling kraken downloads

tests/exchange/test_ccxt_compat.py

@@ -219,7 +219,7 @@ class TestCCXTExchange():
                     assert len(l2['asks']) == next_limit
                     assert len(l2['asks']) == next_limit
 
-    def test_fetch_ohlcv(self, exchange):
+    def test_ccxt_fetch_ohlcv(self, exchange):
         exchange, exchangename = exchange
         pair = EXCHANGES[exchangename]['pair']
         timeframe = EXCHANGES[exchangename]['timeframe']

tests/exchange/test_exchange.py

@@ -1084,6 +1084,13 @@ def test_validate_required_startup_candles(default_conf, mocker, caplog):
     with pytest.raises(OperationalException, match=r'This strategy requires 6000.*'):
         Exchange(default_conf)
 
+    # Emulate kraken mode
+    ex._ft_has['ohlcv_has_history'] = False
+    with pytest.raises(OperationalException,
+                       match=r'This strategy requires 2500.*, '
+                             r'which is more than the amount.*'):
+        ex.validate_required_startup_candles(2500, '5m')
+
 
 def test_exchange_has(default_conf, mocker):
     exchange = get_patched_exchange(mocker, default_conf)