Add tests

src/libstd/collections/hash/map.rs

@@ -1706,6 +1706,20 @@ mod test_map {
         assert_eq!(*m.get(&2).unwrap(), 4);
     }
 
+    #[test]
+    fn test_clone() {
+        let mut m = HashMap::new();
+        assert_eq!(m.len(), 0);
+        assert!(m.insert(1, 2).is_none());
+        assert_eq!(m.len(), 1);
+        assert!(m.insert(2, 4).is_none());
+        assert_eq!(m.len(), 2);
+        let m2 = m.clone();
+        assert_eq!(*m2.get(&1).unwrap(), 2);
+        assert_eq!(*m2.get(&2).unwrap(), 4);
+        assert_eq!(m2.len(), 2);
+    }
+
     thread_local! { static DROP_VECTOR: RefCell<Vec<isize>> = RefCell::new(Vec::new()) }
 
     #[derive(Hash, PartialEq, Eq)]
@@ -1797,7 +1811,7 @@ mod test_map {
     }
 
     #[test]
-    fn test_move_iter_drops() {
+    fn test_into_iter_drops() {
         DROP_VECTOR.with(|v| {
             *v.borrow_mut() = vec![0; 200];
         });
@@ -1862,11 +1876,35 @@ mod test_map {
     }
 
     #[test]
-    fn test_empty_pop() {
+    fn test_empty_remove() {
         let mut m: HashMap<isize, bool> = HashMap::new();
         assert_eq!(m.remove(&0), None);
     }
 
+    #[test]
+    fn test_empty_entry() {
+        let mut m: HashMap<isize, bool> = HashMap::new();
+        match m.entry(0) {
+            Occupied(_) => panic!(),
+            Vacant(_) => {}
+        }
+        assert!(*m.entry(0).or_insert(true));
+        assert_eq!(m.len(), 1);
+    }
+
+    #[test]
+    fn test_empty_iter() {
+        let mut m: HashMap<isize, bool> = HashMap::new();
+        assert_eq!(m.drain().next(), None);
+        assert_eq!(m.keys().next(), None);
+        assert_eq!(m.values().next(), None);
+        assert_eq!(m.iter().next(), None);
+        assert_eq!(m.iter_mut().next(), None);
+        assert_eq!(m.len(), 0);
+        assert!(m.is_empty());
+        assert_eq!(m.into_iter().next(), None);
+    }
+
     #[test]
     fn test_lots_of_insertions() {
         let mut m = HashMap::new();