tests/ui/crashes/auxiliary/proc_macro_crash.rs

   1 // compile-flags: --emit=link
   2 // no-prefer-dynamic
   3 // ^ compiletest by default builds all aux files as dylibs, but we don't want that for proc-macro
   4 // crates. If we don't set this, compiletest will override the `crate_type` attribute below and
   5 // compile this as dylib. Removing this then causes the test to fail because a `dylib` crate can't
   6 // contain a proc-macro.
   7
   8 #![feature(repr128)]
   9 #![allow(incomplete_features)]
  10 #![crate_type = "proc-macro"]
  11
  12 extern crate proc_macro;
  13
  14 use proc_macro::{Delimiter, Group, Ident, Span, TokenStream, TokenTree};
  15
  16 #[proc_macro]
  17 pub fn macro_test(input_stream: TokenStream) -> TokenStream {
  18     let first_token = input_stream.into_iter().next().unwrap();
  19     let span = first_token.span();
  20
  21     TokenStream::from_iter(vec![
  22         TokenTree::Ident(Ident::new("fn", Span::call_site())),
  23         TokenTree::Ident(Ident::new("code", Span::call_site())),
  24         TokenTree::Group(Group::new(Delimiter::Parenthesis, TokenStream::new())),
  25         TokenTree::Group(Group::new(Delimiter::Brace, {
  26             let mut clause = Group::new(Delimiter::Brace, TokenStream::new());
  27             clause.set_span(span);
  28
  29             TokenStream::from_iter(vec![
  30                 TokenTree::Ident(Ident::new("if", Span::call_site())),
  31                 TokenTree::Ident(Ident::new("true", Span::call_site())),
  32                 TokenTree::Group(clause.clone()),
  33                 TokenTree::Ident(Ident::new("else", Span::call_site())),
  34                 TokenTree::Group(clause),
  35             ])
  36         })),
  37     ])
  38 }