Fix implementation; tests passing.

src/main.rs

@@ -4,13 +4,21 @@ struct HashMap<'a, K: PartialEq, V> {
 }
 
 impl<'a, K: PartialEq, V> HashMap<'a, K, V> {
-    fn new(capacity: usize, hash_fn: fn(&K) -> usize) -> Self {
+    fn new(hash_fn: fn(&K) -> usize) -> Self {
         HashMap {
-            table: Vec::with_capacity(capacity),
+            table: vec![None; 16],
             hash_fn,
         }
     }
 
+
+    fn with_capacity(capacity: usize, hash_fn: fn(&K) -> usize) -> Self {
+        HashMap {
+            table: vec![None; capacity],
+            hash_fn
+        }
+    }
+
     fn put(&mut self, k: &'a K, v: &'a V) {
         let hash = (self.hash_fn)(&k);
         let target_index = hash % self.table.capacity();
@@ -55,7 +63,16 @@ mod hash_map_tests {
     fn simple_put_and_get() {
         let jesse = String::from("Jesse");
         let brault = String::from("Brault");
-        let mut map: HashMap<String, String> = HashMap::new(8, |s| s.len());
+        let mut map: HashMap<String, String> = HashMap::new(|s| s.len());
+        map.put(&jesse, &brault);
+        assert_eq!(map.get(&jesse), Some(&brault));
+    }
+
+    #[test]
+    fn put_and_get_with_str() {
+        let jesse = "Jesse";
+        let brault = "Brault";
+        let mut map: HashMap<&str, &str> = HashMap::new(|s| s.len());
         map.put(&jesse, &brault);
         assert_eq!(map.get(&jesse), Some(&brault));
     }