test: Add a new test suite for TSPGenerator with comprehensive covera…

…ge and validation checks

tests/test_generators.py

@@ -544,8 +544,65 @@ def test_generate_custom_size(self):
 
         assert problem.length == size
 
-    def test_generate_maximize(self):
-        """Test generate method with maximize set to True."""
-        problem = QueensGenerator.generate(SEED, maximize=True)
+# noinspection PyTypeChecker
+class TestTSPGenerator:
+
+    def test_generate_invalid_seed(self):
+        """Test generate method raises ValueError when seed is not an integer."""
+        with pytest.raises(ValueError) as excinfo:
+            TSPGenerator.generate(seed="not_an_int", number_of_cities=5)
+        assert str(excinfo.value) == "Seed must be an integer. Got not_an_int"
+
+    def test_generate_invalid_number_of_cities(self):
+        """Test generate method raises ValueError when number_of_cities is not a positive integer."""
+        with pytest.raises(ValueError) as excinfo:
+            TSPGenerator.generate(SEED, number_of_cities=0)
+        assert str(excinfo.value) == "Number of cities must be a positive integer. Got 0"
+
+    def test_generate_invalid_area_width(self):
+        """Test generate method raises ValueError when area_width is not a positive integer."""
+        with pytest.raises(ValueError) as excinfo:
+            TSPGenerator.generate(SEED, number_of_cities=5, area_width=0)
+        assert str(excinfo.value) == "Area width must be a positive integer. Got 0"
 
-        assert problem.maximize == 1.0
+    def test_generate_invalid_area_height(self):
+        """Test generate method raises ValueError when area_height is not a positive integer."""
+        with pytest.raises(ValueError) as excinfo:
+            TSPGenerator.generate(SEED, number_of_cities=5, area_height=0)
+        assert str(excinfo.value) == "Area height must be a positive integer. Got 0"
+
+    def test_generate_default_parameters(self):
+        """Test generate method with default parameters."""
+        problem = TSPGenerator.generate(seed=SEED, number_of_cities=5)
+        assert problem.length == 5
+        assert problem.coords is not None
+        assert problem.distances is not None
+        assert problem.source_graph is not None
+
+    def test_generate_custom_parameters(self):
+        """Test generate method with custom parameters."""
+        problem = TSPGenerator.generate(seed=SEED, number_of_cities=5, area_width=100, area_height=100)
+        assert problem.length == 5
+        assert problem.coords is not None
+        assert problem.distances is not None
+        assert problem.source_graph is not None
+
+    def test_generate_no_duplicate_coordinates(self):
+        """Test generate method ensures no duplicate coordinates."""
+        problem = TSPGenerator.generate(seed=SEED, number_of_cities=5)
+        coords = problem.coords
+        assert len(coords) == len(set(coords))
+
+    def test_generate_distances(self):
+        """Test generate method calculates distances correctly."""
+        problem = TSPGenerator.generate(seed=SEED, number_of_cities=5)
+        distances = problem.distances
+        for u, v, d in distances:
+            assert d == np.linalg.norm(np.subtract(problem.coords[u], problem.coords[v]))
+
+    def test_generate_graph(self):
+        """Test generate method creates a valid graph."""
+        problem = TSPGenerator.generate(seed=SEED, number_of_cities=5)
+        graph = problem.source_graph
+        assert graph.number_of_nodes() == 5
+        assert graph.number_of_edges() == len(problem.distances)