From 3519cebf66e31aa799ae9422ab31e17c20153844 Mon Sep 17 00:00:00 2001
From: Matthias <xmatthias@outlook.com>
Date: Sat, 11 Jan 2020 13:14:19 +0100
Subject: [PATCH] Add test for failing stake_validation

---
 freqtrade/exchange/exchange.py  |  9 +++++----
 tests/exchange/test_exchange.py | 17 +++++++++++++++++
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index a5c10776c..3735dac8a 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -216,8 +216,9 @@ class Exchange:
         Return a list of supported quote currencies
         """
         markets = self.markets
-        currencies = set([x.get('quote') for _, x in markets.items()])
-        return list(currencies)
+        currencies = list(set([x.get('quote') for _, x in markets.items()]))
+        currencies.sort()
+        return currencies
 
     def klines(self, pair_interval: Tuple[str, str], copy=True) -> DataFrame:
         if pair_interval in self._klines:
@@ -277,8 +278,8 @@ class Exchange:
         quote_currencies = self.get_quote_currencies()
         if stake_currency not in quote_currencies:
             raise OperationalException(
-                    f"{stake_currency} is not available as stake on {self.name}."
-                    f"Available currencies are: {','.join(quote_currencies)}")
+                    f"{stake_currency} is not available as stake on {self.name}. "
+                    f"Available currencies are: {', '.join(quote_currencies)}")
 
     def validate_pairs(self, pairs: List[str]) -> None:
         """
diff --git a/tests/exchange/test_exchange.py b/tests/exchange/test_exchange.py
index 5924d4b40..150ba3ea7 100644
--- a/tests/exchange/test_exchange.py
+++ b/tests/exchange/test_exchange.py
@@ -333,6 +333,23 @@ def test_validate_stake_currency(default_conf, stake_currency, mocker, caplog):
     Exchange(default_conf)
 
 
+def test_validate_stake_currency_error(default_conf, mocker, caplog):
+    default_conf['stake_currency'] = 'XRP'
+    api_mock = MagicMock()
+    type(api_mock).markets = PropertyMock(return_value={
+        'ETH/BTC': {'quote': 'BTC'}, 'LTC/BTC': {'quote': 'BTC'},
+        'XRP/ETH': {'quote': 'ETH'}, 'NEO/USDT': {'quote': 'USDT'},
+    })
+    mocker.patch('freqtrade.exchange.Exchange._init_ccxt', MagicMock(return_value=api_mock))
+    mocker.patch('freqtrade.exchange.Exchange.validate_pairs')
+    mocker.patch('freqtrade.exchange.Exchange.validate_timeframes')
+    mocker.patch('freqtrade.exchange.Exchange._load_async_markets')
+    with pytest.raises(OperationalException,
+                       match=r'XRP is not available as stake on .*'
+                       'Available currencies are: BTC, ETH, USDT'):
+        Exchange(default_conf)
+
+
 def test_get_quote_currencies(default_conf, mocker):
     ex = get_patched_exchange(mocker, default_conf)