allow only loading 1 pair if necessary

* simplify tests nad remove unnecessary mocking

freqtrade/data/history.py

@@ -95,6 +95,31 @@ def load_tickerdata_file(
     return pairdata
 
 
+def load_pair_history(pair: str,
+                      ticker_interval: str,
+                      datadir: Optional[Path],
+                      timerange: TimeRange = TimeRange(None, None, 0, 0)) -> DataFrame:
+    """
+    Loads cached ticker history for the given pair.
+    """
+
+    pairdata = load_tickerdata_file(datadir, pair, ticker_interval, timerange=timerange)
+    if pairdata:
+        if timerange.starttype == 'date' and pairdata[0][0] > timerange.startts * 1000:
+            logger.warning('Missing data at start for pair %s, data starts at %s',
+                           pair, arrow.get(pairdata[0][0] // 1000).strftime('%Y-%m-%d %H:%M:%S'))
+        if timerange.stoptype == 'date' and pairdata[-1][0] < timerange.stopts * 1000:
+            logger.warning('Missing data at end for pair %s, data ends at %s',
+                           pair,
+                           arrow.get(pairdata[-1][0] // 1000).strftime('%Y-%m-%d %H:%M:%S'))
+        return parse_ticker_dataframe(pairdata)
+    else:
+        logger.warning('No data for pair: "%s", Interval: %s. '
+                       'Use --refresh-pairs-cached to download the data',
+                       pair, ticker_interval)
+        return None
+
+
 def load_data(datadir: Optional[Path],
               ticker_interval: str,
               pairs: List[str],
@@ -116,22 +141,10 @@ def load_data(datadir: Optional[Path],
         download_pairs(datadir, exchange, pairs, ticker_interval, timerange=timerange)
 
     for pair in pairs:
-        pairdata = load_tickerdata_file(datadir, pair, ticker_interval, timerange=timerange)
+        hist = load_pair_history(pair=pair, ticker_interval=ticker_interval,
-        if pairdata:
+                                 datadir=datadir, timerange=timerange)
-            if timerange.starttype == 'date' and pairdata[0][0] > timerange.startts * 1000:
+        if hist is not None:
-                logger.warning('Missing data at start for pair %s, data starts at %s',
+            result[pair] = hist
-                               pair,
-                               arrow.get(pairdata[0][0] // 1000).strftime('%Y-%m-%d %H:%M:%S'))
-            if timerange.stoptype == 'date' and pairdata[-1][0] < timerange.stopts * 1000:
-                logger.warning('Missing data at end for pair %s, data ends at %s',
-                               pair,
-                               arrow.get(pairdata[-1][0] // 1000).strftime('%Y-%m-%d %H:%M:%S'))
-            result[pair] = parse_ticker_dataframe(pairdata)
-        else:
-            logger.warning('No data for pair: "%s", Interval: %s. '
-                           'Use --refresh-pairs-cached to download the data',
-                           pair, ticker_interval)
-
     return result
 
 

freqtrade/tests/data/test_history.py

@@ -7,6 +7,7 @@ import uuid
 from shutil import copyfile
 
 import arrow
+from pandas import DataFrame
 
 from freqtrade.arguments import TimeRange
 from freqtrade.data import history
@@ -54,26 +55,19 @@ def _clean_test_file(file: str) -> None:
         os.rename(file_swp, file)
 
 
-def test_load_data_30min_ticker(ticker_history, mocker, caplog, default_conf) -> None:
+def test_load_data_30min_ticker(mocker, caplog, default_conf) -> None:
-    mocker.patch('freqtrade.exchange.Exchange.get_history', return_value=ticker_history)
+    ld = history.load_pair_history(pair='UNITTEST/BTC', ticker_interval='30m', datadir=None)
-    file = os.path.join(os.path.dirname(__file__), '..', 'testdata', 'UNITTEST_BTC-30m.json')
+    assert isinstance(ld, DataFrame)
-    _backup_file(file, copy_file=True)
-    ld = history.load_data(datadir=None, pairs=['UNITTEST/BTC'], ticker_interval='30m')
-    assert isinstance(ld, dict)
-    assert os.path.isfile(file) is True
     assert not log_has('Download the pair: "UNITTEST/BTC", Interval: 30m', caplog.record_tuples)
-    _clean_test_file(file)
 
 
-def test_load_data_5min_ticker(ticker_history, mocker, caplog, default_conf) -> None:
+def test_load_data_7min_ticker(mocker, caplog, default_conf) -> None:
-    mocker.patch('freqtrade.exchange.Exchange.get_history', return_value=ticker_history)
+    ld = history.load_pair_history(pair='UNITTEST/BTC', ticker_interval='7m', datadir=None)
-
+    assert not isinstance(ld, DataFrame)
-    file = os.path.join(os.path.dirname(__file__), '..', 'testdata', 'UNITTEST_BTC-5m.json')
+    assert ld is None
-    _backup_file(file, copy_file=True)
+    assert log_has(
-    history.load_data(datadir=None, pairs=['UNITTEST/BTC'], ticker_interval='5m')
+        'No data for pair: "UNITTEST/BTC", Interval: 7m. '
-    assert os.path.isfile(file) is True
+        'Use --refresh-pairs-cached to download the data', caplog.record_tuples)
-    assert not log_has('Download the pair: "UNITTEST/BTC", Interval: 5m', caplog.record_tuples)
-    _clean_test_file(file)
 
 
 def test_load_data_1min_ticker(ticker_history, mocker, caplog) -> None: