use proc_macro2::*; macro_rules! assert_impl { ($ty:ident is $($marker:ident) and +) => { #[test] #[allow(non_snake_case)] fn $ty() { fn assert_implemented() {} assert_implemented::<$ty>(); } }; ($ty:ident is not $($marker:ident) or +) => { #[test] #[allow(non_snake_case)] fn $ty() { $( { // Implemented for types that implement $marker. trait IsNotImplemented { fn assert_not_implemented() {} } impl IsNotImplemented for T {} // Implemented for the type being tested. trait IsImplemented { fn assert_not_implemented() {} } impl IsImplemented for $ty {} // If $ty does not implement $marker, there is no ambiguity // in the following trait method call. <$ty>::assert_not_implemented(); } )+ } }; } assert_impl!(Delimiter is Send and Sync); assert_impl!(Spacing is Send and Sync); assert_impl!(Group is not Send or Sync); assert_impl!(Ident is not Send or Sync); assert_impl!(LexError is not Send or Sync); assert_impl!(Literal is not Send or Sync); assert_impl!(Punct is not Send or Sync); assert_impl!(Span is not Send or Sync); assert_impl!(TokenStream is not Send or Sync); assert_impl!(TokenTree is not Send or Sync); #[cfg(procmacro2_semver_exempt)] mod semver_exempt { use super::*; assert_impl!(LineColumn is Send and Sync); assert_impl!(SourceFile is not Send or Sync); }