Add spread operator test.

src/lexer/mod.rs

@@ -227,4 +227,13 @@ mod tests {
         assert_eq!(Token::CurlyOpen, result[2]);
         assert_eq!(Token::CurlyClose, result[3]);
     }
+
+    #[test]
+    fn spread_operator() {
+        let result = tokenize(&String::from("{ ...props }")).unwrap();
+        assert_eq!(Token::CurlyOpen, result[0]);
+        assert_eq!(Token::Ellipsis, result[1]);
+        assert_eq!(Token::Identifier(String::from("props")), result[2]);
+        assert_eq!(Token::CurlyClose, result[3]);
+    }
 }