tests: add shorthand, unary_operators

src/nodes/tests.rs

@@ -1,9 +1,20 @@
 use std::str::FromStr;
 
-use rug::Float;
+use rug::{Float, ops::CompleteRound};
 
 use crate::nodes::{Function, Node, Nodes, Operator, PREC};
 
+/// shorthand for testing the final output of tylc
+fn num(s: &str) -> Float {
+    Float::parse(s).unwrap().complete(PREC)
+}
+
+#[test]
+fn unary_operators() {
+    assert_eq!(Nodes::from_str("-10").unwrap().evaluate(), num("-10"));
+    assert_eq!(Nodes::from_str("+10").unwrap().evaluate(), num("+10"));
+}
+
 #[test]
 fn test_nodes_to_num() {
     assert_eq!(