add 8, 11, 12

src/assignments/assignment11/graph_grade.rs

@@ -0,0 +1,63 @@
+//! Test cases for assignment11/graph.rs
+
+#[cfg(test)]
+mod test_graph {
+    use super::super::graph::*;
+
+    #[test]
+    fn test_graph() {
+        let mut nodes = (0..6).map(NodeHandle::new).collect::<Vec<_>>();
+        let edges = [
+            (0, 1),
+            (0, 3),
+            (1, 4),
+            (2, 4),
+            (2, 5),
+            (3, 1),
+            (4, 3),
+            (5, 5),
+        ];
+
+        for (from, to) in edges {
+            assert!(nodes[from].add_edge(nodes[to].clone()).unwrap());
+        }
+
+        let mut graph1 = SubGraph::new();
+        for n in 0..6 {
+            assert!(graph1.add_node(nodes[n].clone()));
+        }
+        assert!(graph1.detect_cycle());
+        assert!(!graph1.add_node(nodes[0].clone()));
+
+        let mut graph2 = SubGraph::new();
+        for n in [0, 1, 3] {
+            assert!(graph2.add_node(nodes[n].clone()));
+        }
+        assert!(!graph2.detect_cycle());
+
+        assert!(graph2.add_node(nodes[4].clone()));
+        assert!(graph2.detect_cycle());
+
+        assert!(nodes[4].remove_edge(&nodes[3]).unwrap());
+        assert!(!graph2.detect_cycle());
+
+        let mut graph3 = SubGraph::new();
+        for n in [0, 1, 2, 3] {
+            assert!(graph3.add_node(nodes[n].clone()));
+        }
+        assert!(!graph3.detect_cycle());
+
+        let more_edges = [(1, 2), (2, 3)];
+        for (from, to) in more_edges {
+            assert!(nodes[from].add_edge(nodes[to].clone()).unwrap());
+        }
+        assert!(graph3.detect_cycle());
+
+        assert!(graph3.remove_node(&nodes[2]));
+        assert!(!graph3.detect_cycle());
+
+        for n in nodes {
+            n.clear_edges().unwrap();
+        }
+    }
+}