code: def test_rolling_time_series_split_error():
      """Tests rolling_time_series_split exceptions and warnings"""
      with pytest.warns(Warning) as record:
          RollingTimeSeriesSplit(
              forecast_horizon=3, min_train_periods=4
          )
          assert (
              "`min_train_periods` is too small for your `forecast_horizon`"
              in record[0].message.args[0]
          )
  
      with pytest.warns(Warning) as record:
          X = np.random.rand(12, 1)
          tscv = RollingTimeSeriesSplit(
              forecast_horizon=4, min_train_periods=8
          )
          list(tscv.split(X=X))
          assert (
              "There is only one CV split" in record[0].message.args[0]
          )
  
      with pytest.warns(Warning) as record:
          X = np.random.rand(48, 1)
          tscv = RollingTimeSeriesSplit(
              forecast_horizon=4, min_train_periods=8, max_splits=None
          )
          list(tscv.split(X=X))
          assert (
              "There is a high number of CV splits"
              in record[0].message.args[0]
          )
  
file_path: greykite/greykite/tests/sklearn/test_cross_validation.py
imports: import numpy
  import pytest
  from greykite.sklearn.cross_validation import RollingTimeSeriesSplit
label_desc: Use image node_id 6 for calling a global function with example usage: test_rolling_time_series_split_error() without return types