tests/ui/crashes/auxiliary/proc_macro_crash.rs

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