[test] Add unit tests for RoutingProblem.get_power

tests/test_routing_problem_get_power.py

@@ -0,0 +1,137 @@
+from datetime import datetime, timedelta
+from unittest.mock import MagicMock, patch
+
+import numpy as np
+import pytest
+from astropy import units as u
+
+import tests.basic_test_func as basic_test_func
+from WeatherRoutingTool.algorithms.genetic.problem import RoutingProblem
+
+
+DEPARTURE_TIME = datetime(2025, 4, 1, 11, 11)
+ARRIVAL_TIME = DEPARTURE_TIME + timedelta(hours=10)
+BOAT_SPEED = 6 * u.meter / u.second
+BOAT_SPEED_UNSET = -99. * u.meter / u.second
+
+
+def make_route():
+    lats = np.array([38.192, 38.8, 39.4, 40.0, 40.6, 41.349])
+    lons = np.array([13.392, 11.5, 9.6, 7.7, 5.0, 2.188])
+    speeds = np.full(len(lats), BOAT_SPEED.value)
+    return np.column_stack([lats, lons, speeds])
+
+
+@pytest.fixture(scope="module")
+def boat():
+    return basic_test_func.create_dummy_Direct_Power_Ship("simpleship")
+
+
+@pytest.fixture(scope="module")
+def constraint_list():
+    return basic_test_func.generate_dummy_constraint_list()
+
+
+@pytest.fixture(scope="module")
+def problem_fixed_speed(boat, constraint_list):
+    return RoutingProblem(
+        departure_time=DEPARTURE_TIME,
+        arrival_time=ARRIVAL_TIME,
+        boat=boat,
+        boat_speed=BOAT_SPEED,
+        constraint_list=constraint_list,
+    )
+
+
+@pytest.fixture(scope="module")
+def problem_arrival_time(boat, constraint_list):
+    return RoutingProblem(
+        departure_time=DEPARTURE_TIME,
+        arrival_time=ARRIVAL_TIME,
+        boat=boat,
+        boat_speed=BOAT_SPEED_UNSET,
+        constraint_list=constraint_list,
+    )
+
+
+class TestRoutingProblemInit:
+    def test_fixed_speed_flag_false(self, problem_fixed_speed):
+        assert problem_fixed_speed.boat_speed_from_arrival_time is False
+
+    def test_arrival_time_flag_true(self, problem_arrival_time):
+        assert problem_arrival_time.boat_speed_from_arrival_time is True
+
+
+class TestGetPowerFixedSpeed:
+    def test_returns_tuple(self, problem_fixed_speed):
+        route = make_route()
+        result = problem_fixed_speed.get_power(route)
+        assert isinstance(result, tuple)
+        assert len(result) == 2
+
+    def test_fuel_is_scalar(self, problem_fixed_speed):
+        route = make_route()
+        fuel, _ = problem_fixed_speed.get_power(route)
+        assert np.isscalar(fuel) or fuel.ndim == 0
+
+    def test_fuel_is_positive(self, problem_fixed_speed):
+        route = make_route()
+        fuel, _ = problem_fixed_speed.get_power(route)
+        assert fuel.value > 0
+
+    def test_shipparams_returned(self, problem_fixed_speed):
+        route = make_route()
+        _, shipparams = problem_fixed_speed.get_power(route)
+        assert shipparams is not None
+
+    def test_fuel_reproducible(self, problem_fixed_speed):
+        route = make_route()
+        fuel1, _ = problem_fixed_speed.get_power(route)
+        fuel2, _ = problem_fixed_speed.get_power(route)
+        assert np.isclose(fuel1.value, fuel2.value)
+
+    def test_longer_route_more_fuel(self, problem_fixed_speed):
+        short_route = make_route()[:3]
+        short_speeds = np.full(3, BOAT_SPEED.value)
+        short_route = np.column_stack([short_route[:, 0], short_route[:, 1], short_speeds])
+
+        full_fuel, _ = problem_fixed_speed.get_power(make_route())
+        short_fuel, _ = problem_fixed_speed.get_power(short_route)
+        assert full_fuel.value > short_fuel.value
+
+
+class TestGetPowerArrivalTime:
+    def test_returns_tuple(self, problem_arrival_time):
+        route = make_route()
+        result = problem_arrival_time.get_power(route)
+        assert isinstance(result, tuple)
+        assert len(result) == 2
+
+    def test_fuel_is_positive(self, problem_arrival_time):
+        route = make_route()
+        fuel, _ = problem_arrival_time.get_power(route)
+        assert fuel.value > 0
+
+
+class TestEvaluate:
+    def _run_evaluate(self, problem, fuel_value=5000.0, constraint_value=0):
+        route = make_route()
+        x = np.array([route], dtype=object)
+        out = {}
+        with patch.object(problem, 'get_power', return_value=(fuel_value, MagicMock())), \
+             patch('WeatherRoutingTool.algorithms.genetic.problem.get_constraints', return_value=constraint_value):
+            problem._evaluate(x, out)
+        return out
+
+    def test_out_F_and_G_populated(self, problem_fixed_speed):
+        out = self._run_evaluate(problem_fixed_speed)
+        assert 'F' in out
+        assert 'G' in out
+
+    def test_out_F_is_positive(self, problem_fixed_speed):
+        out = self._run_evaluate(problem_fixed_speed, fuel_value=5000.0)
+        assert out['F'].flat[0] > 0
+
+    def test_out_G_is_zero_when_no_constraints(self, problem_fixed_speed):
+        out = self._run_evaluate(problem_fixed_speed, constraint_value=0)
+        assert out['G'].flat[0] == 0