test

Author: hasnainroopawalla

tests/test_ant.py

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+import pytest
+from unittest.mock import Mock
+
+from aco_routing.ant import Ant
+from aco_routing.graph_api import GraphApi
+
+
+@pytest.fixture
+def mock_graph_api():
+    graph_api = Mock(spec=GraphApi)
+    # Set up a simple graph for testing
+    graph_api.get_neighbors.return_value = ["B", "C"]
+    graph_api.get_edge_pheromones.return_value = 1.0
+    graph_api.get_edge_cost.return_value = 1.0
+    return graph_api
+
+
+def test_ant_initialization(mock_graph_api):
+    ant = Ant(mock_graph_api, source="A", destination="D")
+    assert ant.source == "A"
+    assert ant.destination == "D"
+    assert ant.current_node == "A"
+    assert ant.path == ["A"]
+    assert ant.path_cost == 0.0
+    assert not ant.is_fit
+    assert not ant.is_solution_ant
+    assert len(ant.visited_nodes) == 0
+
+
+def test_reached_destination(mock_graph_api):
+    ant = Ant(mock_graph_api, source="A", destination="D")
+    assert not ant.reached_destination()
+    ant.current_node = "D"
+    assert ant.reached_destination()
+
+
+def test_get_unvisited_neighbors(mock_graph_api):
+    ant = Ant(mock_graph_api, source="A", destination="D")
+    unvisited = ant._get_unvisited_neighbors()
+    assert set(unvisited) == {"B", "C"}
+
+    # Test with some visited nodes
+    ant.visited_nodes.add("B")
+    unvisited = ant._get_unvisited_neighbors()
+    assert unvisited == ["C"]
+
+
+def test_take_step_normal_case(mock_graph_api):
+    ant = Ant(mock_graph_api, source="A", destination="D")
+    ant.take_step()
+    assert ant.current_node in ["B", "C"]  # Should move to one of the neighbors
+    assert len(ant.path) == 2  # Should have two nodes in path [A, (B or C)]
+    assert ant.path_cost == 1.0  # With our mock returning cost=1.0
+    assert len(ant.visited_nodes) == 1  # Should have marked A as visited
+
+
+def test_solution_ant_behavior(mock_graph_api):
+    ant = Ant(mock_graph_api, source="A", destination="D", is_solution_ant=True)
+    # Mock edge pheromones to make B more desirable
+    mock_graph_api.get_edge_pheromones.side_effect = lambda src, dst: (
+        2.0 if dst == "B" else 1.0
+    )
+
+    ant.take_step()
+    assert ant.current_node == "B"  # Should always choose B as it has higher pheromone
+    assert ant.path == ["A", "B"]
+
+
+def test_deposit_pheromones(mock_graph_api):
+    ant = Ant(mock_graph_api, source="A", destination="D")
+    ant.path = ["A", "B", "C"]  # Manually set path for testing
+    ant.path_cost = 2.0
+
+    ant.deposit_pheromones_on_path()
+
+    # Should deposit pheromones on A->B and B->C
+    mock_graph_api.deposit_pheromones.assert_any_call("A", "B", 0.5)
+    mock_graph_api.deposit_pheromones.assert_any_call("B", "C", 0.5)
+    assert mock_graph_api.deposit_pheromones.call_count == 2