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//@ force-host
//@ no-prefer-dynamic
// Proc macro helper for issue #89699, used by tests/ui/proc-macro/edition-gated-async-move-
// syntax-issue89699.rs, emitting an `async move` closure. This syntax is only available in
// editions 2018 and up, but is used in edition 2015 in the test.
#![crate_type = "proc-macro"]
extern crate proc_macro;
use proc_macro::*;
#[proc_macro_attribute]
pub fn foo(_attr: TokenStream, item: TokenStream) -> TokenStream {
let tt = item.into_iter().next().unwrap();
let sp = tt.span();
let mut arg = TokenStream::new();
let mut g = Group::new(Delimiter::Brace, TokenStream::new());
g.set_span(sp);
arg.extend([
TokenTree::Ident(Ident::new("async", sp)),
TokenTree::Ident(Ident::new("move", sp)),
TokenTree::Group(g),
]);
let mut body = TokenStream::new();
body.extend([
TokenTree::Ident(Ident::new("async_main", sp)),
TokenTree::Group(Group::new(Delimiter::Parenthesis, arg)),
]);
let mut ret = TokenStream::new();
ret.extend([
TokenTree::Ident(Ident::new("fn", sp)),
TokenTree::Ident(Ident::new("main", sp)),
TokenTree::Group(Group::new(Delimiter::Parenthesis, TokenStream::new())),
TokenTree::Group(Group::new(Delimiter::Brace, body)),
]);
ret
}
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