Add tests for wind_turbine module

tests/test_wind_turbine.py

@@ -0,0 +1,29 @@
+import pandas as pd
+from pandas.util.testing import assert_series_equal
+import pytest
+
+from windpowerlib.wind_turbine import read_turbine_data, WindTurbine
+
+class TestWindTurbine:
+
+    def test_error_raising(self):
+        self.test_turbine_data = {'hub_height': 100,
+                                  'rotor_diameter': 80,
+                                  'name': 'turbine_not_in_file',
+                                  'fetch_curve': 'power_curve',
+                                  'data_source': 'example_power_curves.csv'}
+        # Raise system exit
+        with pytest.raises(SystemExit):
+            test_turbine = WindTurbine(**self.test_turbine_data)
+
+        # Raise ValueError due to invalid parameter `fetch_curve`
+        self.test_turbine_data['fetch_curve'] = 'misspelling'
+        self.test_turbine_data['name'] = 'DUMMY 3'
+        with pytest.raises(ValueError):
+            test_turbine = WindTurbine(**self.test_turbine_data)
+
+    def test_read_turbine_data(self):
+        # Raise FileNotFoundError due to missing
+        with pytest.raises(FileNotFoundError):
+            read_turbine_data(filename='not_existent')
+