add 8, 11, 12

src/assignments/assignment11/linked_list_grade.rs

@@ -0,0 +1,27 @@
+//! Test cases for assignment11/linked_list.rs
+
+#[cfg(test)]
+mod test_linked_list {
+    use super::super::linked_list::*;
+
+    #[derive(Debug, PartialEq, Eq)]
+    struct V(usize);
+
+    #[test]
+    fn test_linked_list() {
+        let mut list = SinglyLinkedList::new();
+        list.push_back(V(3));
+        list.push_front(V(2));
+        list.push_back(V(4));
+        list.push_front(V(1));
+        list.push_back(V(5));
+
+        assert_eq!(list.pop_front(), Some(V(1)));
+        assert_eq!(list.pop_back(), Some(V(5)));
+        assert_eq!(list.pop_front(), Some(V(2)));
+        assert_eq!(list.pop_back(), Some(V(4)));
+        assert_eq!(list.pop_front(), Some(V(3)));
+        assert_eq!(list.pop_back(), None);
+        assert_eq!(list.pop_front(), None);
+    }
+}