feat(KvStore): new, get, set, remove functions implementation

- Added a new test for empty key

src/lib.rs

@@ -1,20 +1,27 @@
-pub struct KvStore {}
+use std::collections::HashMap;
+
+#[derive(Default)]
+pub struct KvStore {
+    hash_map: HashMap<String, String>,
+}
 
 impl KvStore {
     pub fn new() -> Self {
-        unimplemented!()
+        Self {
+            hash_map: HashMap::new(),
+        }
     }
 
     pub fn set(&mut self, key: String, value: String) {
-        unimplemented!()
+        self.hash_map.insert(key, value);
     }
 
     pub fn get(&mut self, key: String) -> Option<String> {
-        unimplemented!()
+        self.hash_map.get(&key).cloned()
     }
 
     pub fn remove(&mut self, key: String) {
-        unimplemented!()
+        self.hash_map.remove(&key);
     }
 }
 

tests/tests.rs

@@ -153,3 +153,11 @@ fn remove_key() {
     store.remove("key1".to_owned());
     assert_eq!(store.get("key1".to_owned()), None);
 }
+
+#[test]
+fn get_empty_key() {
+    let mut store = KvStore::new();
+
+    store.set("".to_owned(), "value1".to_owned());
+    assert_eq!(store.get("".to_owned()), Some("value1".to_owned()));
+}