futures_await_test_macro/
lib.rs

1#![warn(clippy::pedantic)]
2#![recursion_limit = "4096"]
3
4extern crate proc_macro;
5
6use proc_macro::TokenStream;
7use proc_macro2::Span;
8use quote::quote;
9use syn::{parse_macro_input, parse_quote, Ident, Item, Visibility};
10
11#[proc_macro_attribute]
12pub fn async_test(params: TokenStream, input: TokenStream) -> TokenStream {
13    assert!(
14        params.is_empty(),
15        "the #[async_test] attribute currently does not take parameters"
16    );
17
18    let mut inner = parse_macro_input!(input as Item);
19    let mut outer = inner.clone();
20    if let (&mut Item::Fn(ref mut inner_fn), &mut Item::Fn(ref mut outer_fn)) =
21        (&mut inner, &mut outer)
22    {
23        inner_fn.sig.ident = Ident::new(
24            &("_inner_".to_string() + &inner_fn.sig.ident.to_string()),
25            Span::call_site(),
26        );
27        let inner_ident = &inner_fn.sig.ident;
28        inner_fn.vis = Visibility::Inherited;
29        inner_fn.attrs.clear();
30        assert!(
31            outer_fn.sig.asyncness.take().is_some(),
32            "#[async_test] can only be applied to async functions"
33        );
34        outer_fn.attrs.push(parse_quote!(#[test]));
35        outer_fn.block = Box::new(parse_quote!({
36            ::futures_await_test::reexport::LocalPool::new().run_until(#inner_ident())
37        }));
38    } else {
39        panic!("#[async_test] can only be applied to async functions")
40    }
41    quote!(
42        #inner
43        #outer
44    )
45    .into()
46}
futures_await_test_macro/lib.rs

futures_await_test_macro/
lib.rs
