From 9c9d5baa90383947f6e3ea494a038c840cb6a1c0 Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Mon, 27 Feb 2023 21:25:27 +0000 Subject: [PATCH] Support supertraits-of-supertraits If we have a supertrait that requires an in-crate supertrait, we handle that here by writing the required impls. We don't support a supertrait-of-a-supertrait-of-a-supertrait. --- c-bindings-gen/src/main.rs | 74 +++++++++++++++++++++++++++----------- 1 file changed, 54 insertions(+), 20 deletions(-) diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs index f5a7656..ee800db 100644 --- a/c-bindings-gen/src/main.rs +++ b/c-bindings-gen/src/main.rs @@ -600,18 +600,31 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty (s, i, generic_args) => { if let Some(supertrait) = types.crate_types.traits.get(s) { let resolver = get_module_type_resolver!(s, types.crate_libs, types.crate_types); - - // Blindly assume that the same imports where `supertrait` is defined are also - // imported here. This will almost certainly break at some point, but it should be - // a compilation failure when it does so. - write!(w, "impl").unwrap(); - maybe_write_lifetime_generics(w, &supertrait.generics, types); - write!(w, " {}", s).unwrap(); - maybe_write_generics(w, &supertrait.generics, generic_args, types, false); - writeln!(w, " for {} {{", trait_name).unwrap(); - - impl_trait_for_c!(supertrait, format!(".{}", i), &resolver, generic_args); - writeln!(w, "}}").unwrap(); + macro_rules! impl_supertrait { + ($s: expr, $supertrait: expr, $i: expr, $generic_args: expr) => { + let resolver = get_module_type_resolver!($s, types.crate_libs, types.crate_types); + + // Blindly assume that the same imports where `supertrait` is defined are also + // imported here. This will almost certainly break at some point, but it should be + // a compilation failure when it does so. + write!(w, "impl").unwrap(); + maybe_write_lifetime_generics(w, &$supertrait.generics, types); + write!(w, " {}", $s).unwrap(); + maybe_write_generics(w, &$supertrait.generics, $generic_args, types, false); + writeln!(w, " for {} {{", trait_name).unwrap(); + + impl_trait_for_c!($supertrait, format!(".{}", $i), &resolver, $generic_args); + writeln!(w, "}}").unwrap(); + } + } + impl_supertrait!(s, supertrait, i, generic_args); + walk_supertraits!(supertrait, Some(&resolver), ( + (s, supertrait_i, generic_args) => { + if let Some(supertrait) = types.crate_types.traits.get(s) { + impl_supertrait!(s, supertrait, format!("{}.{}", i, supertrait_i), generic_args); + } + } + ) ); } else { do_write_impl_trait(w, s, i, &trait_name); } @@ -1061,17 +1074,38 @@ fn writeln_impl(w: &mut W, w_uses: &mut HashSet {}, (s, t, _) => { if let Some(supertrait_obj) = types.crate_types.traits.get(s) { - writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap(); - writeln!(w, "\t\t\tthis_arg: unsafe {{ ObjOps::untweak_ptr((*this_arg).inner) as *mut c_void }},").unwrap(); - writeln!(w, "\t\t\tfree: None,").unwrap(); - for item in supertrait_obj.items.iter() { - match item { - syn::TraitItem::Method(m) => { - write_meth!(m, supertrait_obj, "\t"); + macro_rules! write_impl_fields { + ($s: expr, $supertrait_obj: expr, $t: expr, $pfx: expr, $resolver: expr) => { + writeln!(w, "{}\t{}: crate::{} {{", $pfx, $t, $s).unwrap(); + writeln!(w, "{}\t\tthis_arg: unsafe {{ ObjOps::untweak_ptr((*this_arg).inner) as *mut c_void }},", $pfx).unwrap(); + writeln!(w, "{}\t\tfree: None,", $pfx).unwrap(); + for item in $supertrait_obj.items.iter() { + match item { + syn::TraitItem::Method(m) => { + write_meth!(m, $supertrait_obj, $pfx); + }, + _ => {}, + } + } + walk_supertraits!($supertrait_obj, Some(&$resolver), ( + ("Clone", _, _) => { + writeln!(w, "{}\tcloned: Some({}_{}_cloned),", $pfx, $supertrait_obj.ident, ident).unwrap(); }, - _ => {}, + (_, _, _) => {} + ) ); } } + write_impl_fields!(s, supertrait_obj, t, "\t", types); + + let resolver = get_module_type_resolver!(s, types.crate_libs, types.crate_types); + walk_supertraits!(supertrait_obj, Some(&resolver), ( + (s, t, _) => { + if let Some(supertrait_obj) = types.crate_types.traits.get(s) { + write_impl_fields!(s, supertrait_obj, t, "\t\t", resolver); + write!(w, "\t\t\t}},\n").unwrap(); + } + } + ) ); write!(w, "\t\t}},\n").unwrap(); } else { write_trait_impl_field_assign(w, s, ident); -- 2.39.5