def test_forecast(reading, expected_forecast, monkeypatch, mock_ws):
'''
1. Assume that the forecaster module imports an external module weatherservice and
then instantiates it in the constructor.
2. In this case you cannot inject a mock into forecaster's constructor.
3. Therefore, use a monkeypatching. Pytest will only patch a value for the duration
of the test and then remove it.
'''
WS = Mock(return_value=mock_ws)
monkeypatch.setattr('forecaster.WeatherService', WS)
forecaster = Forecaster()
mock_ws.barometer.return_value = reading
assert forecaster.forecast() == expected_forecast
from forecaster import Forecaster
import pandas as pd
import numpy as np
covid = pd.read_csv("covid_19_data.csv")
covid["ObservationDate"] = pd.to_datetime(covid["ObservationDate"])
covid.drop(columns=["SNo"], inplace=True)
def incidence_denv(xdata, c1, c2, c3, c4=0):
ans = [c1 * np.exp(-((t - c2)**2) / c3) + c4 for t in xdata]
return ans
caster = Forecaster(covid, "Mainland China", incidence_denv)
print("Done 1")
caster.forecast()
caster.plot()