Merge pull request #3260 from topecongiro/issue-3004

Do not modify original source code inside macro call

tests/source/macros.rs

@@ -466,3 +466,8 @@ macro_rules! bar {
         RefCell::new(RootedTraceableSet::new(1234)) ;
 
 ] ;
+
+fn issue3004() {
+    foo!(|_| { (  ) });
+    stringify!(( foo+ ));
+}