Add test for root node

tests/block.rs

@@ -30,17 +30,3 @@ fn async_with_return() {
         Ok(Value::Integer(1))
     );
 }
-
-#[test]
-fn root_returns_like_block() {
-    assert_eq!(
-        interpret(
-            "
-                return 1
-                1 + 1
-                3
-                "
-        ),
-        Ok(Value::Integer(1))
-    );
-}

tests/root.rs

@@ -0,0 +1,29 @@
+use dust_lang::*;
+
+#[test]
+fn returns_final_statement() {
+    assert_eq!(
+        interpret(
+            "
+                1
+                1 + 1
+                3
+                "
+        ),
+        Ok(Value::Integer(3))
+    );
+}
+
+#[test]
+fn return_statement() {
+    assert_eq!(
+        interpret(
+            "
+                return 1
+                1 + 1
+                3
+                "
+        ),
+        Ok(Value::Integer(1))
+    );
+}