[fine] A wild VM appears!

Untested though

fine/build.rs

@@ -82,6 +82,11 @@ fn generate_test_for_file(path: PathBuf) -> String {
             assertions.push(quote! {
                 crate::assert_no_errors(&_tree, &_lines);
             });
+        } else if let Some(line) = line.strip_prefix("@eval:") {
+            let expected = line.trim();
+            assertions.push(quote! {
+                crate::assert_eval_ok(&_tree, &_lines, #expected);
+            });
         } else if line.starts_with("@") {
             panic!("Test file {display_path} has unknown directive: {line}");
         }