test: Improve test coverage of retry/fail logic

freqtrade/exchange/exchange.py

@@ -662,7 +662,7 @@ class Exchange:
         logger.debug("Performing scheduled market reload..")
         try:
             # on initial load, we retry 3 times to ensure we get the markets
-            retries = 3 if force else 1
+            retries = 3 if force else 0
             # Reload async markets, then assign them to sync api
             self._markets = retrier(self._load_async_markets, retries=retries)(reload=True)
             self._api.set_markets(self._api_async.markets, self._api_async.currencies)

tests/exchange/test_exchange.py

@@ -638,6 +638,21 @@ def test_reload_markets(default_conf, mocker, caplog, time_machine):
     exchange.reload_markets()
     assert lam_spy.call_count == 0
 
+    # Another reload should happen but it fails.
+    time_machine.move_to(start_dt + timedelta(minutes=51), tick=False)
+    api_mock.load_markets = get_mock_coro(side_effect=ccxt.NetworkError("LoadError"))
+
+    exchange.reload_markets(force=False)
+    assert exchange.markets == updated_markets
+    assert lam_spy.call_count == 1
+    # Tried once, failed
+
+    lam_spy.reset_mock()
+    # When forceing (bot startup), it should retry 3 times.
+    exchange.reload_markets(force=True)
+    assert lam_spy.call_count == 4
+    assert exchange.markets == updated_markets
+
 
 def test_reload_markets_exception(default_conf, mocker, caplog):
     caplog.set_level(logging.DEBUG)