diff options
Diffstat (limited to 'tests/ui/proc-macro/auxiliary/attribute-spans-preserved.rs')
-rw-r--r-- | tests/ui/proc-macro/auxiliary/attribute-spans-preserved.rs | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/tests/ui/proc-macro/auxiliary/attribute-spans-preserved.rs b/tests/ui/proc-macro/auxiliary/attribute-spans-preserved.rs new file mode 100644 index 000000000..4d3279584 --- /dev/null +++ b/tests/ui/proc-macro/auxiliary/attribute-spans-preserved.rs @@ -0,0 +1,35 @@ +// force-host +// no-prefer-dynamic + +#![crate_type = "proc-macro"] + +extern crate proc_macro; + +use proc_macro::*; + +#[proc_macro_attribute] +pub fn foo(attr: TokenStream, f: TokenStream) -> TokenStream { + let mut tokens = f.into_iter(); + assert_eq!(tokens.next().unwrap().to_string(), "#"); + let next_attr = match tokens.next().unwrap() { + TokenTree::Group(g) => g, + _ => panic!(), + }; + + let fn_tok = tokens.next().unwrap(); + let ident_tok = tokens.next().unwrap(); + let args_tok = tokens.next().unwrap(); + let body = tokens.next().unwrap(); + + let new_body = attr.into_iter() + .chain(next_attr.stream().into_iter().skip(1)); + + let tokens = vec![ + fn_tok, + ident_tok, + args_tok, + Group::new(Delimiter::Brace, new_body.collect()).into(), + ].into_iter().collect::<TokenStream>(); + println!("{}", tokens); + return tokens +} |